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Merge remote-tracking branch 'upstream/master'

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This commit is contained in:
Andrea
2018-03-11 21:54:59 +01:00
parent c5ac4b4bba f50d111c5e
commit b832ed0af8
740 changed files with 15628 additions and 3857 deletions
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core-java/src/main/java/com/baeldung/array/Find2ndLargestInArray.java
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package com.baeldung.array;
public class Find2ndLargestInArray {
public static int find2ndLargestElement(int[] array) {
int maxElement = array[0];
int secondLargestElement = -1;
for (int index = 0; index < array.length; index++) {
if (maxElement <= array[index]) {
secondLargestElement = maxElement;
maxElement = array[index];
} else if (secondLargestElement < array[index]) {
secondLargestElement = array[index];
}
}
return secondLargestElement;
}
}
core-java/src/main/java/com/baeldung/array/FindElementInArray.java
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package com.baeldung.array;
import java.util.Arrays;
public class FindElementInArray {
public static boolean findGivenElementInArrayWithoutUsingStream(int[] array, int element) {
boolean actualResult = false;
for (int index = 0; index < array.length; index++) {
if (element == array[index]) {
actualResult = true;
break;
}
}
return actualResult;
}
public static boolean findGivenElementInArrayUsingStream(int[] array, int element) {
return Arrays.stream(array).filter(x -> element == x).findFirst().isPresent();
}
}
core-java/src/main/java/com/baeldung/array/SumAndAverageInArray.java
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package com.baeldung.array;
import java.util.Arrays;
public class SumAndAverageInArray {
public static int findSumWithoutUsingStream(int[] array) {
int sum = 0;
for (int index = 0; index < array.length; index++) {
sum += array[index];
}
return sum;
}
public static int findSumUsingStream(int[] array) {
return Arrays.stream(array).sum();
}
public static double findAverageWithoutUsingStream(int[] array) {
int sum = findSumWithoutUsingStream(array);
return (double) sum / array.length;
}
public static double findAverageUsingStream(int[] array) {
return Arrays.stream(array).average().getAsDouble();
}
}
core-java/src/main/java/com/baeldung/asciiart/AsciiArt.java
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package com.baeldung.asciiart;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.RenderingHints;
import java.awt.image.BufferedImage;
public class AsciiArt {
public AsciiArt() {
}
public void drawString(String text, String artChar, Settings settings) {
BufferedImage image = getImageIntegerMode(settings.width, settings.height);
Graphics2D graphics2D = getGraphics2D(image.getGraphics(), settings);
graphics2D.drawString(text, 6, ((int) (settings.height * 0.67)));
for (int y = 0; y < settings.height; y++) {
StringBuilder stringBuilder = new StringBuilder();
for (int x = 0; x < settings.width; x++) {
stringBuilder.append(image.getRGB(x, y) == -16777216 ? " " : artChar);
}
if (stringBuilder.toString()
.trim()
.isEmpty()) {
continue;
}
System.out.println(stringBuilder);
}
}
private BufferedImage getImageIntegerMode(int width, int height) {
return new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
}
private Graphics2D getGraphics2D(Graphics graphics, Settings settings) {
graphics.setFont(settings.font);
Graphics2D graphics2D = (Graphics2D) graphics;
graphics2D.setRenderingHint(RenderingHints.KEY_TEXT_ANTIALIASING, RenderingHints.VALUE_TEXT_ANTIALIAS_ON);
return graphics2D;
}
public class Settings {
public Font font;
public int width;
public int height;
public Settings(Font font, int width, int height) {
this.font = font;
this.width = width;
this.height = height;
}
}
}
core-java/src/main/java/com/baeldung/casting/Animal.java
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package com.baeldung.casting;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
public class Animal {
private static final Logger LOGGER = LoggerFactory.getLogger(Animal.class);
public void eat() {
LOGGER.info("animal is eating");
}
}
core-java/src/main/java/com/baeldung/casting/AnimalFeeder.java
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package com.baeldung.casting;
import java.util.List;
public class AnimalFeeder {
public void feed(List<Animal> animals) {
animals.forEach(animal -> {
animal.eat();
if (animal instanceof Cat) {
((Cat) animal).meow();
}
});
}
public void uncheckedFeed(List<Animal> animals) {
animals.forEach(animal -> {
animal.eat();
((Cat) animal).meow();
});
}
}
core-java/src/main/java/com/baeldung/casting/AnimalFeederGeneric.java
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package com.baeldung.casting;
import java.util.ArrayList;
import java.util.List;
public class AnimalFeederGeneric<T> {
private Class<T> type;
public AnimalFeederGeneric(Class<T> type) {
this.type = type;
}
public List<T> feed(List<Animal> animals) {
List<T> list = new ArrayList<T>();
animals.forEach(animal -> {
if (type.isInstance(animal)) {
T objAsType = type.cast(animal);
list.add(objAsType);
}
});
return list;
}
}
core-java/src/main/java/com/baeldung/casting/Cat.java
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package com.baeldung.casting;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
public class Cat extends Animal implements Mew {
private static final Logger LOGGER = LoggerFactory.getLogger(Cat.class);
public void eat() {
LOGGER.info("cat is eating");
}
public void meow() {
LOGGER.info("meow");
}
}
core-java/src/main/java/com/baeldung/casting/Dog.java
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package com.baeldung.casting;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
public class Dog extends Animal {
private static final Logger LOGGER = LoggerFactory.getLogger(Dog.class);
public void eat() {
LOGGER.info("dog is eating");
}
}
core-java/src/main/java/com/baeldung/casting/Mew.java
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package com.baeldung.casting;
public interface Mew {
public void meow();
}
core-java/src/main/java/com/baeldung/classloader/CustomClassLoader.java
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package com.baeldung.classloader;
import java.io.*;
public class CustomClassLoader extends ClassLoader {
public Class getClass(String name) throws ClassNotFoundException {
byte[] b = loadClassFromFile(name);
return defineClass(name, b, 0, b.length);
}
private byte[] loadClassFromFile(String fileName) {
InputStream inputStream = getClass().getClassLoader().getResourceAsStream(
fileName.replace('.', File.separatorChar) + ".class");
byte[] buffer;
ByteArrayOutputStream byteStream = new ByteArrayOutputStream();
int nextValue = 0;
try {
while ( (nextValue = inputStream.read()) != -1 ) {
byteStream.write(nextValue);
}
} catch (IOException e) {
e.printStackTrace();
}
buffer = byteStream.toByteArray();
return buffer;
}
}
core-java/src/main/java/com/baeldung/classloader/PrintClassLoader.java
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package com.baeldung.classloader;
import com.sun.javafx.util.Logging;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.MalformedURLException;
import java.net.URL;
import java.net.URLConnection;
import java.util.ArrayList;
public class PrintClassLoader {
public void printClassLoaders() throws ClassNotFoundException {
System.out.println("Classloader of this class:" + PrintClassLoader.class.getClassLoader());
System.out.println("Classloader of Logging:" + Logging.class.getClassLoader());
System.out.println("Classloader of ArrayList:" + ArrayList.class.getClassLoader());
}
}
core-java/src/main/java/com/baeldung/deepcopy/Address.java
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package com.baeldung.deepcopy;
import java.io.Serializable;
public class Address implements Serializable, Cloneable {
@Override
public Object clone() {
try {
return (Address) super.clone();
} catch (CloneNotSupportedException e) {
return new Address(this.street, this.getCity(), this.getCountry());
}
}
private static final long serialVersionUID = 1740913841244949416L;
private String street;
private String city;
private String country;
public Address(Address that) {
this(that.getStreet(), that.getCity(), that.getCountry());
}
public Address(String street, String city, String country) {
this.street = street;
this.city = city;
this.country = country;
}
public Address() {
}
public String getStreet() {
return street;
}
public String getCity() {
return city;
}
public String getCountry() {
return country;
}
public void setStreet(String street) {
this.street = street;
}
public void setCity(String city) {
this.city = city;
}
public void setCountry(String country) {
this.country = country;
}
}
core-java/src/main/java/com/baeldung/deepcopy/User.java
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package com.baeldung.deepcopy;
import java.io.Serializable;
public class User implements Serializable, Cloneable {
private static final long serialVersionUID = -3427002229954777557L;
private String firstName;
private String lastName;
private Address address;
public User(String firstName, String lastName, Address address) {
this.firstName = firstName;
this.lastName = lastName;
this.address = address;
}
public User(User that) {
this(that.getFirstName(), that.getLastName(), new Address(that.getAddress()));
}
public User() {
}
@Override
public Object clone() {
User user;
try {
user = (User) super.clone();
} catch (CloneNotSupportedException e) {
user = new User(this.getFirstName(), this.getLastName(), this.getAddress());
}
user.address = (Address) this.address.clone();
return user;
}
public String getFirstName() {
return firstName;
}
public String getLastName() {
return lastName;
}
public Address getAddress() {
return address;
}
}
core-java/src/main/java/com/baeldung/designpatterns/flyweight/Car.java
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package com.baeldung.designpatterns.flyweight;
import java.awt.Color;
import javax.annotation.concurrent.Immutable;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* Represents a car. This class is immutable.
*
* @author Donato Rimenti
*/
@Immutable
public class Car implements Vehicle {
/**
* Logger.
*/
private final static Logger LOG = LoggerFactory.getLogger(Car.class);
/**
* The car's engine.
*/
private Engine engine;
/**
* The car's color.
*/
private Color color;
/**
* Instantiates a new Car.
*
* @param engine
* the {@link #engine}
* @param color
* the {@link #color}
*/
public Car(Engine engine, Color color) {
this.engine = engine;
this.color = color;
// Building a new car is a very expensive operation!
try {
Thread.sleep(2000);
} catch (InterruptedException e) {
LOG.error("Error while creating a new car", e);
}
}
/*
* (non-Javadoc)
*
* @see com.baeldung.designpatterns.flyweight.Vehicle#start()
*/
@Override
public void start() {
LOG.info("Car is starting!");
engine.start();
}
/*
* (non-Javadoc)
*
* @see com.baeldung.designpatterns.flyweight.Vehicle#stop()
*/
@Override
public void stop() {
LOG.info("Car is stopping!");
engine.stop();
}
/*
* (non-Javadoc)
*
* @see com.baeldung.designpatterns.flyweight.Vehicle#getColor()
*/
@Override
public Color getColor() {
return this.color;
}
}
core-java/src/main/java/com/baeldung/designpatterns/flyweight/Engine.java
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package com.baeldung.designpatterns.flyweight;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* Engine for a vehicle.
*
* @author Donato Rimenti
*/
public class Engine {
/**
* Logger.
*/
private final static Logger LOG = LoggerFactory.getLogger(Engine.class);
/**
* Starts the engine.
*/
public void start() {
LOG.info("Engine is starting!");
}
/**
* Stops the engine.
*/
public void stop() {
LOG.info("Engine is stopping!");
}
}
core-java/src/main/java/com/baeldung/designpatterns/flyweight/Vehicle.java
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package com.baeldung.designpatterns.flyweight;
import java.awt.Color;
/**
* Interface for a vehicle.
*
* @author Donato Rimenti
*/
public interface Vehicle {
/**
* Starts the vehicle.
*/
public void start();
/**
* Stops the vehicle.
*/
public void stop();
/**
* Gets the color of the vehicle.
*
* @return the color of the vehicle
*/
public Color getColor();
}
core-java/src/main/java/com/baeldung/designpatterns/flyweight/VehicleFactory.java
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package com.baeldung.designpatterns.flyweight;
import java.awt.Color;
import java.util.HashMap;
import java.util.Map;
/**
* Factory which implements the Flyweight pattern to return an existing vehicle
* if present or a new one otherwise.
*
* @author Donato Rimenti
*/
public class VehicleFactory {
/**
* Stores the already created vehicles.
*/
private static Map<Color, Vehicle> vehiclesCache = new HashMap<Color, Vehicle>();
/**
* Private constructor to prevent this class instantiation.
*/
private VehicleFactory() {
}
/**
* Returns a vehicle of the same color passed as argument. If that vehicle
* was already created by this factory, that vehicle is returned, otherwise
* a new one is created and returned.
*
* @param color
* the color of the vehicle to return
* @return a vehicle of the specified color
*/
public static Vehicle createVehicle(Color color) {
// Looks for the requested vehicle into the cache.
// If the vehicle doesn't exist, a new one is created.
Vehicle newVehicle = vehiclesCache.computeIfAbsent(color, newColor -> {
// Creates the new car.
Engine newEngine = new Engine();
return new Car(newEngine, newColor);
});
return newVehicle;
}
}
core-java/src/main/java/com/baeldung/inheritance/ArmoredCar.java
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package com.baeldung.inheritance;
public class ArmoredCar extends Car implements Floatable, Flyable{
private int bulletProofWindows;
private String model;
public void remoteStartCar() {
// this vehicle can be started by using a remote control
}
public String registerModel() {
return model;
}
public String getAValue() {
return super.model; // returns value of model defined in base class Car
// return this.model; // will return value of model defined in ArmoredCar
// return model; // will return value of model defined in ArmoredCar
}
public static String msg() {
// return super.msg(); // this won't compile.
return "ArmoredCar";
}
@Override
public void floatOnWater() {
System.out.println("I can float!");
}
@Override
public void fly() {
System.out.println("I can fly!");
}
public void aMethod() {
// System.out.println(duration); // Won't compile
System.out.println(Floatable.duration); // outputs 10
System.out.println(Flyable.duration); // outputs 20
}
}
core-java/src/main/java/com/baeldung/inheritance/BMW.java
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package com.baeldung.inheritance;
public class BMW extends Car {
public BMW() {
super(5, "BMW");
}
@Override
public String toString() {
return model;
}
}
core-java/src/main/java/com/baeldung/inheritance/Car.java
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package com.baeldung.inheritance;
public class Car {
private final int DEFAULT_WHEEL_COUNT = 5;
private final String DEFAULT_MODEL = "Basic";
protected int wheels;
protected String model;
public Car() {
this.wheels = DEFAULT_WHEEL_COUNT;
this.model = DEFAULT_MODEL;
}
public Car(int wheels, String model) {
this.wheels = wheels;
this.model = model;
}
public void start() {
// Check essential parts
// If okay, start.
}
public static int count = 10;
public static String msg() {
return "Car";
}
public String toString() {
return model;
}
}
core-java/src/main/java/com/baeldung/inheritance/Employee.java
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package com.baeldung.inheritance;
public class Employee {
private String name;
private Car car;
public Employee(String name, Car car) {
this.name = name;
this.car = car;
}
public Car getCar() {
return car;
}
}
core-java/src/main/java/com/baeldung/inheritance/Floatable.java
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@@ -0,0 +1,10 @@
package com.baeldung.inheritance;
public interface Floatable {
int duration = 10;
void floatOnWater();
default void repair() {
System.out.println("Repairing Floatable object");
}
}
core-java/src/main/java/com/baeldung/inheritance/Flyable.java
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@@ -0,0 +1,13 @@
package com.baeldung.inheritance;
public interface Flyable {
int duration = 10;
void fly();
/*
* Commented
*/
//default void repair() {
// System.out.println("Repairing Flyable object");
//}
}
core-java/src/main/java/com/baeldung/inheritance/SpaceCar.java
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@@ -0,0 +1,18 @@
package com.baeldung.inheritance;
public class SpaceCar extends Car implements SpaceTraveller {
@Override
public void floatOnWater() {
System.out.println("SpaceCar floating!");
}
@Override
public void fly() {
System.out.println("SpaceCar flying!");
}
@Override
public void remoteControl() {
System.out.println("SpaceCar being controlled remotely!");
}
}
core-java/src/main/java/com/baeldung/inheritance/SpaceTraveller.java
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package com.baeldung.inheritance;
public interface SpaceTraveller extends Floatable, Flyable {
int duration = 10;
void remoteControl();
}
core-java/src/main/java/com/baeldung/java/list/CustomList.java
+210
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@@ -0,0 +1,210 @@
package com.baeldung.java.list;
import java.util.Arrays;
import java.util.Collection;
import java.util.Iterator;
import java.util.List;
import java.util.ListIterator;
public class CustomList<E> implements List<E> {
private Object[] internal = {};
@Override
public boolean isEmpty() {
// the first cycle
// return true;
// the second cycle
// if (internal.length != 0) {
// return false;
// } else {
// return true;
// }
// refactoring
return internal.length == 0;
}
@Override
public int size() {
// the first cycle
// if (isEmpty()) {
// return 0;
// } else {
// return internal.length;
// }
// refactoring
return internal.length;
}
@SuppressWarnings("unchecked")
@Override
public E get(int index) {
// the first cycle
// return (E) internal[0];
// improvement
return (E) internal[index];
}
@Override
public boolean add(E element) {
// the first cycle
// internal = new Object[] { element };
// return true;
// the second cycle
Object[] temp = Arrays.copyOf(internal, internal.length + 1);
temp[internal.length] = element;
internal = temp;
return true;
}
@Override
public void add(int index, E element) {
throw new UnsupportedOperationException();
}
@Override
public boolean addAll(Collection<? extends E> collection) {
throw new UnsupportedOperationException();
}
@Override
public boolean addAll(int index, Collection<? extends E> collection) {
throw new UnsupportedOperationException();
}
@Override
public E remove(int index) {
throw new UnsupportedOperationException();
}
@Override
public boolean remove(Object object) {
throw new UnsupportedOperationException();
}
@Override
public boolean removeAll(Collection<?> collection) {
throw new UnsupportedOperationException();
}
@Override
public boolean retainAll(Collection<?> collection) {
throw new UnsupportedOperationException();
}
@Override
public boolean contains(Object object) {
for (Object element : internal) {
if (object.equals(element)) {
return true;
}
}
return false;
}
@Override
public boolean containsAll(Collection<?> collection) {
for (Object element : collection)
if (!contains(element)) {
return false;
}
return true;
}
@SuppressWarnings("unchecked")
@Override
public E set(int index, E element) {
E oldElement = (E) internal[index];
internal[index] = element;
return oldElement;
}
@Override
public void clear() {
internal = new Object[0];
}
@Override
public int indexOf(Object object) {
for (int i = 0; i < internal.length; i++) {
if (object.equals(internal[i])) {
return i;
}
}
return -1;
}
@Override
public int lastIndexOf(Object object) {
for (int i = internal.length - 1; i >= 0; i--) {
if (object.equals(internal[i])) {
return i;
}
}
return -1;
}
@SuppressWarnings("unchecked")
@Override
public List<E> subList(int fromIndex, int toIndex) {
Object[] temp = new Object[toIndex - fromIndex];
System.arraycopy(internal, fromIndex, temp, 0, temp.length);
return (List<E>) Arrays.asList(temp);
}
@Override
public Object[] toArray() {
return Arrays.copyOf(internal, internal.length);
}
@SuppressWarnings("unchecked")
@Override
public <T> T[] toArray(T[] array) {
if (array.length < internal.length) {
return (T[]) Arrays.copyOf(internal, internal.length, array.getClass());
}
System.arraycopy(internal, 0, array, 0, internal.length);
if (array.length > internal.length) {
array[internal.length] = null;
}
return array;
}
@Override
public Iterator<E> iterator() {
return new CustomIterator();
}
@Override
public ListIterator<E> listIterator() {
return null;
}
@Override
public ListIterator<E> listIterator(int index) {
// ignored for brevity
return null;
}
private class CustomIterator implements Iterator<E> {
int index;
@Override
public boolean hasNext() {
return index != internal.length;
}
@SuppressWarnings("unchecked")
@Override
public E next() {
E element = (E) CustomList.this.internal[index];
index++;
return element;
}
}
}
core-java/src/main/java/com/baeldung/javadoc/SuperHero.java
+7 -1
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@@ -23,9 +23,15 @@ public class SuperHero extends Person {
* @return the amount of health hero has after attack
* @see <a href="http://www.link_to_jira/HERO-402">HERO-402</a>
* @since 1.0
* @deprecated As of version 1.1, use . . . instead
* @version 1.2
* @throws IllegalArgumentException if incomingDamage is negative
*/
public int successfullyAttacked(int incomingDamage, String damageType) {
public int successfullyAttacked(int incomingDamage, String damageType) throws Exception {
// do things
if (incomingDamage < 0) {
throw new IllegalArgumentException ("Cannot cause negative damage");
}
return 0;
}
core-java/src/main/java/com/baeldung/methodoverloadingoverriding/application/Application.java
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package com.baeldung.methodoverloadingoverriding.application;
import com.baeldung.methodoverloadingoverriding.model.Car;
import com.baeldung.methodoverloadingoverriding.model.Vehicle;
import com.baeldung.methodoverloadingoverriding.util.Multiplier;
public class Application {
public static void main(String[] args) {
Multiplier multiplier = new Multiplier();
System.out.println(multiplier.multiply(10, 10));
System.out.println(multiplier.multiply(10, 10, 10));
System.out.println(multiplier.multiply(10, 10.5));
System.out.println(multiplier.multiply(10.5, 10.5));
Vehicle vehicle = new Vehicle();
System.out.println(vehicle.accelerate(100));
System.out.println(vehicle.run());
System.out.println(vehicle.stop());
Vehicle car = new Car();
System.out.println(car.accelerate(80));
System.out.println(car.run());
System.out.println(car.stop());
}
}
core-java/src/main/java/com/baeldung/methodoverloadingoverriding/model/Car.java
+9
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package com.baeldung.methodoverloadingoverriding.model;
public class Car extends Vehicle {
@Override
public String accelerate(long mph) {
return "The car accelerates at : " + mph + " MPH.";
}
}
core-java/src/main/java/com/baeldung/methodoverloadingoverriding/model/Vehicle.java
+16
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@@ -0,0 +1,16 @@
package com.baeldung.methodoverloadingoverriding.model;
public class Vehicle {
public String accelerate(long mph) {
return "The vehicle accelerates at : " + mph + " MPH.";
}
public String stop() {
return "The vehicle has stopped.";
}
public String run() {
return "The vehicle is running.";
}
}
core-java/src/main/java/com/baeldung/methodoverloadingoverriding/util/Multiplier.java
+16
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package com.baeldung.methodoverloadingoverriding.util;
public class Multiplier {
public int multiply(int a, int b) {
return a * b;
}
public int multiply(int a, int b, int c) {
return a * b * c;
}
public double multiply(double a, double b) {
return a * b;
}
}
core-java/src/main/java/com/baeldung/recursion/BinaryNode.java
+31
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package com.baeldung.recursion;
public class BinaryNode {
int value;
BinaryNode left;
BinaryNode right;
public BinaryNode(int value){
this.value = value;
}
public int getValue() {
return value;
}
public void setValue(int value) {
this.value = value;
}
public BinaryNode getLeft() {
return left;
}
public void setLeft(BinaryNode left) {
this.left = left;
}
public BinaryNode getRight() {
return right;
}
public void setRight(BinaryNode right) {
this.right = right;
}
}
core-java/src/main/java/com/baeldung/recursion/RecursionExample.java
+64
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package com.baeldung.recursion;
public class RecursionExample {
public int sum(int n){
if (n >= 1){
return sum(n - 1) + n;
}
return n;
}
public int tailSum(int currentSum, int n){
if (n <= 1) {
return currentSum + n;
}
return tailSum(currentSum + n, n - 1);
}
public int iterativeSum(int n){
int sum = 0;
if(n < 0){
return -1;
}
for(int i=0; i<=n; i++){
sum += i;
}
return sum;
}
public int powerOf10(int n){
if (n == 0){
return 1;
}
return powerOf10(n-1)*10;
}
public int fibonacci(int n){
if (n <=1 ){
return n;
}
return fibonacci(n-1) + fibonacci(n-2);
}
public String toBinary(int n){
if (n <= 1 ){
return String.valueOf(n);
}
return toBinary(n / 2) + String.valueOf(n % 2);
}
public int calculateTreeHeight(BinaryNode root){
if (root!= null){
if (root.getLeft() != null || root.getRight() != null){
return 1 + max(calculateTreeHeight(root.left) , calculateTreeHeight(root.right));
}
}
return 0;
}
public int max(int a,int b){
return a>b ? a:b;
}
}
core-java/src/main/java/com/baeldung/resourcebundle/ExampleControl.java
+15
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package com.baeldung.resourcebundle;
import java.util.Arrays;
import java.util.List;
import java.util.Locale;
import java.util.ResourceBundle;
public class ExampleControl extends ResourceBundle.Control {
@Override
public List<Locale> getCandidateLocales(String s, Locale locale) {
return Arrays.asList(new Locale("pl", "PL"));
}
}
core-java/src/main/java/com/baeldung/resourcebundle/ExampleResource.java
+14
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package com.baeldung.resourcebundle;
import java.util.ListResourceBundle;
public class ExampleResource extends ListResourceBundle {
@Override
protected Object[][] getContents() {
return new Object[][] {
{ "greeting", "hello" }
};
}
}
core-java/src/main/java/com/baeldung/resourcebundle/ExampleResource_pl.java
+15
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package com.baeldung.resourcebundle;
import java.util.ListResourceBundle;
public class ExampleResource_pl extends ListResourceBundle {
@Override
protected Object[][] getContents() {
return new Object[][] {
{ "greeting", "cześć" },
{ "language", "polish" },
};
}
}
core-java/src/main/java/com/baeldung/resourcebundle/ExampleResource_pl_PL.java
+17
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@@ -0,0 +1,17 @@
package com.baeldung.resourcebundle;
import java.math.BigDecimal;
import java.util.ListResourceBundle;
public class ExampleResource_pl_PL extends ListResourceBundle {
@Override
protected Object[][] getContents() {
return new Object[][] {
{ "currency", "polish zloty" },
{ "toUsdRate", new BigDecimal("3.401") },
{ "cities", new String[] { "Warsaw", "Cracow" } }
};
}
}
core-java/src/main/java/com/baeldung/system/DetectOS.java
+18
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package com.baeldung.system;
import org.apache.commons.lang3.SystemUtils;
public class DetectOS {
public String getOperatingSystem() {
String os = System.getProperty("os.name");
System.out.println("Using System Property: " + os);
return os;
}
public String getOperatingSystemSystemUtils() {
String os = SystemUtils.OS_NAME;
System.out.println("Using SystemUtils: " + os);
return os;
}
}
core-java/src/main/resources/resourcebundle/resource.properties
+6
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# Buttons
cancelButton=cancel
continueButton continue
! Labels
helloLabel:hello
core-java/src/main/resources/resourcebundle/resource_en.properties
+1
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@@ -0,0 +1 @@
deleteButton=delete
core-java/src/main/resources/resourcebundle/resource_pl_PL.properties
+3
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@@ -0,0 +1,3 @@
backButton=cofnij
helloLabel=cze\u015b\u0107
helloLabelNoEncoding=cześć
core-java/src/main/resources/targetFile.tmp
-2
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@@ -1,2 +0,0 @@
line 1
a second line
core-java/src/test/java/com/baeldung/array/Find2ndLargestInArrayTest.java
+16
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package com.baeldung.array;
import org.junit.Assert;
import org.junit.Test;
public class Find2ndLargestInArrayTest {
@Test
public void givenAnIntArray_thenFind2ndLargestElement() {
int[] array = { 1, 3, 24, 16, 87, 20 };
int expected2ndLargest = 24;
int actualSecondLargestElement = Find2ndLargestInArray.find2ndLargestElement(array);
Assert.assertEquals(expected2ndLargest, actualSecondLargestElement);
}
}
core-java/src/test/java/com/baeldung/array/FindElementInArrayTest.java
+35
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package com.baeldung.array;
import org.junit.Assert;
import org.junit.Test;
public class FindElementInArrayTest {
@Test
public void givenAnIntArray_whenNotUsingStream_thenFindAnElement() {
int[] array = { 1, 3, 4, 8, 19, 20 };
int element = 19;
boolean expectedResult = true;
boolean actualResult = FindElementInArray.findGivenElementInArrayWithoutUsingStream(array, element);
Assert.assertEquals(expectedResult, actualResult);
element = 78;
expectedResult = false;
actualResult = FindElementInArray.findGivenElementInArrayWithoutUsingStream(array, element);
Assert.assertEquals(expectedResult, actualResult);
}
@Test
public void givenAnIntArray_whenUsingStream_thenFindAnElement() {
int[] array = { 15, 16, 12, 18 };
int element = 16;
boolean expectedResult = true;
boolean actualResult = FindElementInArray.findGivenElementInArrayUsingStream(array, element);
Assert.assertEquals(expectedResult, actualResult);
element = 20;
expectedResult = false;
actualResult = FindElementInArray.findGivenElementInArrayUsingStream(array, element);
Assert.assertEquals(expectedResult, actualResult);
}
}
core-java/src/test/java/com/baeldung/array/SumAndAverageInArrayTest.java
+41
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package com.baeldung.array;
import org.junit.Assert;
import org.junit.Test;
public class SumAndAverageInArrayTest {
@Test
public void givenAnIntArray_whenNotUsingStream_thenFindSum() {
int[] array = { 1, 3, 4, 8, 19, 20 };
int expectedSumOfArray = 55;
int actualSumOfArray = SumAndAverageInArray.findSumWithoutUsingStream(array);
Assert.assertEquals(expectedSumOfArray, actualSumOfArray);
}
@Test
public void givenAnIntArray_whenUsingStream_thenFindSum() {
int[] array = { 1, 3, 4, 8, 19, 20 };
int expectedSumOfArray = 55;
int actualSumOfArray = SumAndAverageInArray.findSumUsingStream(array);
Assert.assertEquals(expectedSumOfArray, actualSumOfArray);
}
@Test
public void givenAnIntArray_whenNotUsingStream_thenFindAverage() {
int[] array = { 1, 3, 4, 8, 19, 20 };
double expectedAvgOfArray = 9.17;
double actualAvgOfArray = SumAndAverageInArray.findAverageWithoutUsingStream(array);
Assert.assertEquals(expectedAvgOfArray, actualAvgOfArray, 0.0034);
}
@Test
public void givenAnIntArray_whenUsingStream_thenFindAverage() {
int[] array = { 1, 3, 4, 8, 19, 20 };
double expectedAvgOfArray = 9.17;
double actualAvgOfArray = SumAndAverageInArray.findAverageUsingStream(array);
Assert.assertEquals(expectedAvgOfArray, actualAvgOfArray, 0.0034);
}
}
core-java/src/test/java/com/baeldung/asciiart/AsciiArtTest.java
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package com.baeldung.asciiart;
import java.awt.Font;
import org.junit.Test;
import com.baeldung.asciiart.AsciiArt.Settings;
public class AsciiArtTest {
@Test
public void givenTextWithAsciiCharacterAndSettings_shouldPrintAsciiArt() {
AsciiArt asciiArt = new AsciiArt();
String text = "BAELDUNG";
Settings settings = asciiArt.new Settings(new Font("SansSerif", Font.BOLD, 24), text.length() * 30, 30); // 30 pixel width per character
asciiArt.drawString(text, "*", settings);
}
}
core-java/src/test/java/com/baeldung/casting/CastingTest.java
+80
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package com.baeldung.casting;
import org.junit.Test;
import static org.junit.Assert.*;
import java.util.ArrayList;
import java.util.List;
public class CastingTest {
@Test
public void whenPrimitiveConverted_thenValueChanged() {
double myDouble = 1.1;
int myInt = (int) myDouble;
assertNotEquals(myDouble, myInt);
}
@Test
public void whenUpcast_thenInstanceUnchanged() {
Cat cat = new Cat();
Animal animal = cat;
animal = (Animal) cat;
assertTrue(animal instanceof Cat);
}
@Test
public void whenUpcastToObject_thenInstanceUnchanged() {
Object object = new Animal();
assertTrue(object instanceof Animal);
}
@Test
public void whenUpcastToInterface_thenInstanceUnchanged() {
Mew mew = new Cat();
assertTrue(mew instanceof Cat);
}
@Test
public void whenUpcastToAnimal_thenOverridenMethodsCalled() {
List<Animal> animals = new ArrayList<>();
animals.add(new Cat());
animals.add(new Dog());
new AnimalFeeder().feed(animals);
}
@Test
public void whenDowncastToCat_thenMeowIsCalled() {
Animal animal = new Cat();
((Cat) animal).meow();
}
@Test(expected = ClassCastException.class)
public void whenDownCastWithoutCheck_thenExceptionThrown() {
List<Animal> animals = new ArrayList<>();
animals.add(new Cat());
animals.add(new Dog());
new AnimalFeeder().uncheckedFeed(animals);
}
@Test
public void whenDowncastToCatWithCastMethod_thenMeowIsCalled() {
Animal animal = new Cat();
if (Cat.class.isInstance(animal)) {
Cat cat = Cat.class.cast(animal);
cat.meow();
}
}
@Test
public void whenParameterCat_thenOnlyCatsFed() {
List<Animal> animals = new ArrayList<>();
animals.add(new Cat());
animals.add(new Dog());
AnimalFeederGeneric<Cat> catFeeder = new AnimalFeederGeneric<Cat>(Cat.class);
List<Cat> fedAnimals = catFeeder.feed(animals);
assertTrue(fedAnimals.size() == 1);
assertTrue(fedAnimals.get(0) instanceof Cat);
}
}
core-java/src/test/java/com/baeldung/classloader/CustomClassLoaderTest.java
+23
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package com.baeldung.classloader;
import org.junit.Test;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
public class CustomClassLoaderTest {
@Test
public void customLoader() throws ClassNotFoundException, IllegalAccessException, InstantiationException, NoSuchMethodException, InvocationTargetException {
CustomClassLoader customClassLoader = new CustomClassLoader();
Class<?> c = customClassLoader.getClass(PrintClassLoader.class.getName());
Object ob = c.newInstance();
Method md = c.getMethod("printClassLoaders");
md.invoke(ob);
}
}
core-java/src/test/java/com/baeldung/classloader/PrintClassLoaderTest.java
+14
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@@ -0,0 +1,14 @@
package com.baeldung.classloader;
import org.junit.Test;
import static org.junit.Assert.*;
public class PrintClassLoaderTest {
@Test(expected = ClassNotFoundException.class)
public void givenAppClassLoader_whenParentClassLoader_thenClassNotFoundException() throws Exception {
PrintClassLoader sampleClassLoader = (PrintClassLoader) Class.forName(PrintClassLoader.class.getName()).newInstance();
sampleClassLoader.printClassLoaders();
Class.forName(PrintClassLoader.class.getName(), true, PrintClassLoader.class.getClassLoader().getParent());
}
}
core-java/src/test/java/com/baeldung/deepcopy/DeepCopyUnitTest.java
+128
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package com.baeldung.deepcopy;
import static org.assertj.core.api.Assertions.assertThat;
import java.io.IOException;
import org.apache.commons.lang.SerializationUtils;
import org.junit.Ignore;
import org.junit.Test;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.google.gson.Gson;
public class DeepCopyUnitTest {
@Test
public void whenCreatingDeepCopyWithCopyConstructor_thenObjectsShouldNotBeSame() {
Address address = new Address("Downing St 10", "London", "England");
User pm = new User("Prime", "Minister", address);
User deepCopy = new User(pm);
assertThat(deepCopy).isNotSameAs(pm);
}
@Test
public void whenModifyingOriginalObject_thenConstructorCopyShouldNotChange() {
Address address = new Address("Downing St 10", "London", "England");
User pm = new User("Prime", "Minister", address);
User deepCopy = new User(pm);
address.setCountry("Great Britain");
assertThat(deepCopy.getAddress().getCountry()).isNotEqualTo(pm.getAddress().getCountry());
}
@Test
public void whenModifyingOriginalObject_thenCloneCopyShouldNotChange() {
Address address = new Address("Downing St 10", "London", "England");
User pm = new User("Prime", "Minister", address);
User deepCopy = (User) pm.clone();
address.setCountry("Great Britain");
assertThat(deepCopy.getAddress().getCountry()).isNotEqualTo(pm.getAddress().getCountry());
}
@Test
public void whenModifyingOriginalObject_thenCommonsCloneShouldNotChange() {
Address address = new Address("Downing St 10", "London", "England");
User pm = new User("Prime", "Minister", address);
User deepCopy = (User) SerializationUtils.clone(pm);
address.setCountry("Great Britain");
assertThat(deepCopy.getAddress().getCountry()).isNotEqualTo(pm.getAddress().getCountry());
}
@Test
public void whenModifyingOriginalObject_thenGsonCloneShouldNotChange() {
Address address = new Address("Downing St 10", "London", "England");
User pm = new User("Prime", "Minister", address);
Gson gson = new Gson();
User deepCopy = gson.fromJson(gson.toJson(pm), User.class);
address.setCountry("Great Britain");
assertThat(deepCopy.getAddress().getCountry()).isNotEqualTo(pm.getAddress().getCountry());
}
@Test
public void whenModifyingOriginalObject_thenJacksonCopyShouldNotChange() throws IOException {
Address address = new Address("Downing St 10", "London", "England");
User pm = new User("Prime", "Minister", address);
ObjectMapper objectMapper = new ObjectMapper();
User deepCopy = objectMapper.readValue(objectMapper.writeValueAsString(pm), User.class);
address.setCountry("Great Britain");
assertThat(deepCopy.getAddress().getCountry()).isNotEqualTo(pm.getAddress().getCountry());
}
@Test
@Ignore
public void whenMakingCopies_thenShowHowLongEachMethodTakes() throws CloneNotSupportedException, IOException {
int times = 1000000;
Address address = new Address("Downing St 10", "London", "England");
User pm = new User("Prime", "Minister", address);
long start = System.currentTimeMillis();
for (int i = 0; i < times; i++) {
User primeMinisterClone = (User) SerializationUtils.clone(pm);
}
long end = System.currentTimeMillis();
System.out.println("Cloning with Apache Commons Lang took " + (end - start) + " milliseconds.");
start = System.currentTimeMillis();
Gson gson = new Gson();
for (int i = 0; i < times; i++) {
User primeMinisterClone = gson.fromJson(gson.toJson(pm), User.class);
}
end = System.currentTimeMillis();
System.out.println("Cloning with Gson took " + (end - start) + " milliseconds.");
start = System.currentTimeMillis();
for (int i = 0; i < times; i++) {
User primeMinisterClone = new User(pm);
}
end = System.currentTimeMillis();
System.out.println("Cloning with the copy constructor took " + (end - start) + " milliseconds.");
start = System.currentTimeMillis();
for (int i = 0; i < times; i++) {
User primeMinisterClone = (User) pm.clone();
}
end = System.currentTimeMillis();
System.out.println("Cloning with Cloneable interface took " + (end - start) + " milliseconds.");
start = System.currentTimeMillis();
ObjectMapper objectMapper = new ObjectMapper();
for (int i = 0; i < times; i++) {
User primeMinisterClone = objectMapper.readValue(objectMapper.writeValueAsString(pm), User.class);
}
end = System.currentTimeMillis();
System.out.println("Cloning with Jackson took " + (end - start) + " milliseconds.");
}
}
core-java/src/test/java/com/baeldung/deepcopy/ShallowCopyUnitTest.java
+33
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package com.baeldung.deepcopy;
import static org.assertj.core.api.Assertions.assertThat;
import org.junit.Test;
public class ShallowCopyUnitTest {
@Test
public void whenShallowCopying_thenObjectsShouldNotBeSame() {
Address address = new Address("Downing St 10", "London", "England");
User pm = new User("Prime", "Minister", address);
User shallowCopy = new User(pm.getFirstName(), pm.getLastName(), pm.getAddress());
assertThat(shallowCopy)
.isNotSameAs(pm);
}
@Test
public void whenModifyingOriginalObject_thenCopyShouldChange() {
Address address = new Address("Downing St 10", "London", "England");
User pm = new User("Prime", "Minister", address);
User shallowCopy = new User(pm.getFirstName(), pm.getLastName(), pm.getAddress());
address.setCountry("Great Britain");
assertThat(shallowCopy.getAddress().getCountry())
.isEqualTo(pm.getAddress().getCountry());
}
}
core-java/src/test/java/com/baeldung/designpatterns/flyweight/FlyweightUnitTest.java
+42
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package com.baeldung.designpatterns.flyweight;
import java.awt.Color;
import org.junit.Assert;
import org.junit.Test;
/**
* Unit test for {@link VehicleFactory}.
*
* @author Donato Rimenti
*/
public class FlyweightUnitTest {
/**
* Checks that when the {@link VehicleFactory} is asked to provide two
* vehicles of different colors, the objects returned are different.
*/
@Test
public void givenDifferentFlyweightObjects_whenEquals_thenFalse() {
Vehicle blackVehicle = VehicleFactory.createVehicle(Color.BLACK);
Vehicle blueVehicle = VehicleFactory.createVehicle(Color.BLUE);
Assert.assertNotNull("Object returned by the factory is null!", blackVehicle);
Assert.assertNotNull("Object returned by the factory is null!", blueVehicle);
Assert.assertNotEquals("Objects returned by the factory are equals!", blackVehicle, blueVehicle);
}
/**
* Checks that when the {@link VehicleFactory} is asked to provide two
* vehicles of the same colors, the same object is returned twice.
*/
@Test
public void givenSameFlyweightObjects_whenEquals_thenTrue() {
Vehicle blackVehicle = VehicleFactory.createVehicle(Color.BLACK);
Vehicle anotherBlackVehicle = VehicleFactory.createVehicle(Color.BLACK);
Assert.assertNotNull("Object returned by the factory is null!", blackVehicle);
Assert.assertNotNull("Object returned by the factory is null!", anotherBlackVehicle);
Assert.assertEquals("Objects returned by the factory are not equals!", blackVehicle, anotherBlackVehicle);
}
}
core-java/src/test/java/com/baeldung/inheritance/AppTest.java
+46
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package com.baeldung.inheritance;
import com.baeldung.inheritance.*;
import junit.framework.Test;
import junit.framework.TestCase;
import junit.framework.TestSuite;
public class AppTest extends TestCase {
public AppTest(String testName) {
super( testName );
}
public static Test suite() {
return new TestSuite(AppTest.class);
}
@SuppressWarnings("static-access")
public void testStaticMethodUsingBaseClassVariable() {
Car first = new ArmoredCar();
assertEquals("Car", first.msg());
}
@SuppressWarnings("static-access")
public void testStaticMethodUsingDerivedClassVariable() {
ArmoredCar second = new ArmoredCar();
assertEquals("ArmoredCar", second.msg());
}
public void testAssignArmoredCarToCar() {
Employee e1 = new Employee("Shreya", new ArmoredCar());
assertNotNull(e1.getCar());
}
public void testAssignSpaceCarToCar() {
Employee e2 = new Employee("Paul", new SpaceCar());
assertNotNull(e2.getCar());
}
public void testBMWToCar() {
Employee e3 = new Employee("Pavni", new BMW());
assertNotNull(e3.getCar());
}
}
core-java/src/test/java/com/baeldung/java/list/CustomListUnitTest.java
+296
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package com.baeldung.java.list;
import static org.junit.Assert.assertArrayEquals;
import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertFalse;
import static org.junit.Assert.assertNull;
import static org.junit.Assert.assertTrue;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Iterator;
import java.util.List;
import org.junit.Test;
public class CustomListUnitTest {
@Test
public void givenEmptyList_whenIsEmpty_thenTrueIsReturned() {
List<Object> list = new CustomList<>();
assertTrue(list.isEmpty());
}
@Test
public void givenNonEmptyList_whenIsEmpty_thenFalseIsReturned() {
List<Object> list = new CustomList<>();
list.add(null);
assertFalse(list.isEmpty());
}
@Test
public void givenListWithAnElement_whenSize_thenOneIsReturned() {
List<Object> list = new CustomList<>();
list.add(null);
assertEquals(1, list.size());
}
@Test
public void givenListWithAnElement_whenGet_thenThatElementIsReturned() {
List<Object> list = new CustomList<>();
list.add("baeldung");
Object element = list.get(0);
assertEquals("baeldung", element);
}
@Test
public void givenEmptyList_whenElementIsAdded_thenGetReturnsThatElement() {
List<Object> list = new CustomList<>();
boolean succeeded = list.add(null);
assertTrue(succeeded);
}
@Test
public void givenListWithAnElement_whenAnotherIsAdded_thenGetReturnsBoth() {
List<Object> list = new CustomList<>();
list.add("baeldung");
list.add(".com");
Object element1 = list.get(0);
Object element2 = list.get(1);
assertEquals("baeldung", element1);
assertEquals(".com", element2);
}
@Test(expected = UnsupportedOperationException.class)
public void whenAddToSpecifiedIndex_thenExceptionIsThrown() {
new CustomList<>().add(0, null);
}
@Test(expected = UnsupportedOperationException.class)
public void whenAddAllToTheEnd_thenExceptionIsThrown() {
Collection<Object> collection = new ArrayList<>();
List<Object> list = new CustomList<>();
list.addAll(collection);
}
@Test(expected = UnsupportedOperationException.class)
public void whenAddAllToSpecifiedIndex_thenExceptionIsThrown() {
Collection<Object> collection = new ArrayList<>();
List<Object> list = new CustomList<>();
list.addAll(0, collection);
}
@Test(expected = UnsupportedOperationException.class)
public void whenRemoveAtSpecifiedIndex_thenExceptionIsThrown() {
List<Object> list = new CustomList<>();
list.add("baeldung");
list.remove(0);
}
@Test(expected = UnsupportedOperationException.class)
public void whenRemoveSpecifiedElement_thenExceptionIsThrown() {
List<Object> list = new CustomList<>();
list.add("baeldung");
list.remove("baeldung");
}
@Test(expected = UnsupportedOperationException.class)
public void whenRemoveAll_thenExceptionIsThrown() {
Collection<Object> collection = new ArrayList<>();
collection.add("baeldung");
List<Object> list = new CustomList<>();
list.removeAll(collection);
}
@Test(expected = UnsupportedOperationException.class)
public void whenRetainAll_thenExceptionIsThrown() {
Collection<Object> collection = new ArrayList<>();
collection.add("baeldung");
List<Object> list = new CustomList<>();
list.add("baeldung");
list.retainAll(collection);
}
@Test
public void givenEmptyList_whenContains_thenFalseIsReturned() {
List<Object> list = new CustomList<>();
assertFalse(list.contains(null));
}
@Test
public void givenListWithAnElement_whenContains_thenTrueIsReturned() {
List<Object> list = new CustomList<>();
list.add("baeldung");
assertTrue(list.contains("baeldung"));
}
@Test
public void givenListWithAnElement_whenContainsAll_thenTrueIsReturned() {
Collection<Object> collection = new ArrayList<>();
collection.add("baeldung");
List<Object> list = new CustomList<>();
list.add("baeldung");
assertTrue(list.containsAll(collection));
}
@Test
public void givenList_whenContainsAll_thenEitherTrueOrFalseIsReturned() {
Collection<Object> collection1 = new ArrayList<>();
collection1.add("baeldung");
collection1.add(".com");
Collection<Object> collection2 = new ArrayList<>();
collection2.add("baeldung");
List<Object> list = new CustomList<>();
list.add("baeldung");
assertFalse(list.containsAll(collection1));
assertTrue(list.containsAll(collection2));
}
@Test
public void givenList_whenSet_thenOldElementIsReturned() {
List<Object> list = new CustomList<>();
list.add("baeldung");
Object element = list.set(0, null);
assertEquals("baeldung", element);
assertNull(list.get(0));
}
@Test
public void givenList_whenClear_thenAllElementsAreRemoved() {
List<Object> list = new CustomList<>();
list.add("baeldung");
list.clear();
assertTrue(list.isEmpty());
}
@Test
public void givenList_whenIndexOf_thenIndexZeroIsReturned() {
List<Object> list = new CustomList<>();
list.add("baeldung");
assertEquals(0, list.indexOf("baeldung"));
}
@Test
public void givenList_whenIndexOf_thenPositiveIndexOrMinusOneIsReturned() {
List<Object> list = new CustomList<>();
list.add("baeldung");
list.add(".com");
list.add(".com");
assertEquals(1, list.indexOf(".com"));
assertEquals(-1, list.indexOf("com"));
}
@Test
public void whenLastIndexOf_thenIndexZeroIsReturned() {
List<Object> list = new CustomList<>();
list.add("baeldung");
assertEquals(0, list.lastIndexOf("baeldung"));
}
@Test
public void whenLastIndexOf_thenPositiveIndexOrMinusOneIsReturned() {
List<Object> list = new CustomList<>();
list.add("baeldung");
list.add("baeldung");
list.add(".com");
assertEquals(1, list.lastIndexOf("baeldung"));
assertEquals(-1, list.indexOf("com"));
}
@Test
public void whenSubListZeroToOne_thenListContainingFirstElementIsReturned() {
List<Object> list = new CustomList<>();
list.add("baeldung");
List<Object> subList = list.subList(0, 1);
assertEquals("baeldung", subList.get(0));
}
@Test
public void whenSubListOneToTwo_thenListContainingSecondElementIsReturned() {
List<Object> list = new CustomList<>();
list.add("baeldung");
list.add(".");
list.add("com");
List<Object> subList = list.subList(1, 2);
assertEquals(1, subList.size());
assertEquals(".", subList.get(0));
}
@Test
public void givenListWithElements_whenToArray_thenArrayContainsThose() {
List<Object> list = new CustomList<>();
list.add("baeldung");
list.add(".com");
Object[] array = list.toArray();
assertArrayEquals(new Object[] { "baeldung", ".com" }, array);
}
@Test
public void givenListWithAnElement_whenToArray_thenInputArrayIsReturned() {
List<Object> list = new CustomList<>();
list.add("baeldung");
String[] input = new String[1];
String[] output = list.toArray(input);
assertArrayEquals(new String[] { "baeldung" }, input);
}
@Test
public void whenToArrayIsCalledWithEmptyInputArray_thenNewArrayIsReturned() {
List<Object> list = new CustomList<>();
list.add("baeldung");
String[] input = {};
String[] output = list.toArray(input);
assertArrayEquals(new String[] { "baeldung" }, output);
}
@Test
public void whenToArrayIsCalledWithLargerInput_thenOutputHasTrailingNull() {
List<Object> list = new CustomList<>();
list.add("baeldung");
String[] input = new String[2];
String[] output = list.toArray(input);
assertArrayEquals(new String[] { "baeldung", null }, output);
}
@Test
public void givenListWithOneElement_whenIterator_thenThisElementIsNext() {
List<Object> list = new CustomList<>();
list.add("baeldung");
Iterator<Object> iterator = list.iterator();
assertTrue(iterator.hasNext());
assertEquals("baeldung", iterator.next());
}
@Test
public void whenIteratorHasNextIsCalledTwice_thenTheSecondReturnsFalse() {
List<Object> list = new CustomList<>();
list.add("baeldung");
Iterator<Object> iterator = list.iterator();
iterator.next();
assertFalse(iterator.hasNext());
}
}
core-java/src/test/java/com/baeldung/methodoverloadingoverriding/test/MethodOverloadingUnitTest.java
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package com.baeldung.methodoverloadingoverriding.test;
import com.baeldung.methodoverloadingoverriding.util.Multiplier;
import org.junit.BeforeClass;
import org.junit.Test;
import static org.assertj.core.api.Assertions.*;
public class MethodOverloadingUnitTest {
private static Multiplier multiplier;
@BeforeClass
public static void setUpMultiplierInstance() {
multiplier = new Multiplier();
}
@Test
public void givenMultiplierInstance_whenCalledMultiplyWithTwoIntegers_thenOneAssertion() {
assertThat(multiplier.multiply(10, 10)).isEqualTo(100);
}
@Test
public void givenMultiplierInstance_whenCalledMultiplyWithTreeIntegers_thenOneAssertion() {
assertThat(multiplier.multiply(10, 10, 10)).isEqualTo(1000);
}
@Test
public void givenMultiplierInstance_whenCalledMultiplyWithIntDouble_thenOneAssertion() {
assertThat(multiplier.multiply(10, 10.5)).isEqualTo(105.0);
}
@Test
public void givenMultiplierInstance_whenCalledMultiplyWithDoubleDouble_thenOneAssertion() {
assertThat(multiplier.multiply(10.5, 10.5)).isEqualTo(110.25);
}
@Test
public void givenMultiplierInstance_whenCalledMultiplyWithIntIntAndMatching_thenNoTypePromotion() {
assertThat(multiplier.multiply(10, 10)).isEqualTo(100);
}
}
core-java/src/test/java/com/baeldung/methodoverloadingoverriding/test/MethodOverridingUnitTest.java
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package com.baeldung.methodoverloadingoverriding.test;
import com.baeldung.methodoverloadingoverriding.model.Car;
import com.baeldung.methodoverloadingoverriding.model.Vehicle;
import org.junit.BeforeClass;
import org.junit.Test;
import static org.assertj.core.api.Assertions.*;
public class MethodOverridingUnitTest {
private static Vehicle vehicle;
private static Car car;
@BeforeClass
public static void setUpVehicleInstance() {
vehicle = new Vehicle();
}
@BeforeClass
public static void setUpCarInstance() {
car = new Car();
}
@Test
public void givenVehicleInstance_whenCalledAccelerate_thenOneAssertion() {
assertThat(vehicle.accelerate(100)).isEqualTo("The vehicle accelerates at : 100 MPH.");
}
@Test
public void givenVehicleInstance_whenCalledRun_thenOneAssertion() {
assertThat(vehicle.run()).isEqualTo("The vehicle is running.");
}
@Test
public void givenVehicleInstance_whenCalledStop_thenOneAssertion() {
assertThat(vehicle.stop()).isEqualTo("The vehicle has stopped.");
}
@Test
public void givenCarInstance_whenCalledAccelerate_thenOneAssertion() {
assertThat(car.accelerate(80)).isEqualTo("The car accelerates at : 80 MPH.");
}
@Test
public void givenCarInstance_whenCalledRun_thenOneAssertion() {
assertThat(car.run()).isEqualTo("The vehicle is running.");
}
@Test
public void givenCarInstance_whenCalledStop_thenOneAssertion() {
assertThat(car.stop()).isEqualTo("The vehicle has stopped.");
}
@Test
public void givenVehicleCarInstances_whenCalledAccelerateWithSameArgument_thenNotEqual() {
assertThat(vehicle.accelerate(100)).isNotEqualTo(car.accelerate(100));
}
@Test
public void givenVehicleCarInstances_whenCalledRun_thenEqual() {
assertThat(vehicle.run()).isEqualTo(car.run());
}
@Test
public void givenVehicleCarInstances_whenCalledStop_thenEqual() {
assertThat(vehicle.stop()).isEqualTo(car.stop());
}
}
core-java/src/test/java/com/baeldung/recursion/RecursionExampleTest.java
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package com.baeldung.recursion;
import org.junit.Assert;
import org.junit.Test;
public class RecursionExampleTest {
RecursionExample recursion = new RecursionExample();
@Test
public void testPowerOf10() {
int p0 = recursion.powerOf10(0);
int p1 = recursion.powerOf10(1);
int p4 = recursion.powerOf10(4);
Assert.assertEquals(1, p0);
Assert.assertEquals(10, p1);
Assert.assertEquals(10000, p4);
}
@Test
public void testFibonacci() {
int n0 = recursion.fibonacci(0);
int n1 = recursion.fibonacci(1);
int n7 = recursion.fibonacci(7);
Assert.assertEquals(0, n0);
Assert.assertEquals(1, n1);
Assert.assertEquals(13, n7);
}
@Test
public void testToBinary() {
String b0 = recursion.toBinary(0);
String b1 = recursion.toBinary(1);
String b10 = recursion.toBinary(10);
Assert.assertEquals("0", b0);
Assert.assertEquals("1", b1);
Assert.assertEquals("1010", b10);
}
@Test
public void testCalculateTreeHeight() {
BinaryNode root = new BinaryNode(1);
root.setLeft(new BinaryNode(1));
root.setRight(new BinaryNode(1));
root.getLeft().setLeft(new BinaryNode(1));
root.getLeft().getLeft().setRight(new BinaryNode(1));
root.getLeft().getLeft().getRight().setLeft(new BinaryNode(1));
root.getRight().setLeft(new BinaryNode(1));
root.getRight().getLeft().setRight(new BinaryNode(1));
int height = recursion.calculateTreeHeight(root);
Assert.assertEquals(4, height);
}
}
core-java/src/test/java/com/baeldung/resourcebundle/ExampleResourceUnitTest.java
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package com.baeldung.resourcebundle;
import org.junit.Test;
import java.math.BigDecimal;
import java.util.Arrays;
import java.util.Locale;
import java.util.ResourceBundle;
import static org.junit.Assert.*;
public class ExampleResourceUnitTest {
@Test
public void whenGetBundleExampleResourceForLocalePlPl_thenItShouldInheritPropertiesGreetingAndLanguage() {
Locale plLocale = new Locale("pl", "PL");
ResourceBundle exampleBundle = ResourceBundle.getBundle("com.baeldung.resourcebundle.ExampleResource", plLocale);
assertTrue(exampleBundle.keySet()
.containsAll(Arrays.asList("toUsdRate", "cities", "greeting", "currency", "language")));
assertEquals(exampleBundle.getString("greeting"), "cześć");
assertEquals(exampleBundle.getObject("toUsdRate"), new BigDecimal("3.401"));
assertArrayEquals(exampleBundle.getStringArray("cities"), new String[] { "Warsaw", "Cracow" });
}
@Test
public void whenGetBundleExampleResourceForLocaleUs_thenItShouldContainOnlyGreeting() {
Locale usLocale = Locale.US;
ResourceBundle exampleBundle = ResourceBundle.getBundle("com.baeldung.resourcebundle.ExampleResource", usLocale);
assertFalse(exampleBundle.keySet()
.containsAll(Arrays.asList("toUsdRate", "cities", "currency", "language")));
assertTrue(exampleBundle.keySet()
.containsAll(Arrays.asList("greeting")));
}
}
core-java/src/test/java/com/baeldung/resourcebundle/PropertyResourceUnitTest.java
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package com.baeldung.resourcebundle;
import org.junit.Test;
import java.util.Arrays;
import java.util.Locale;
import java.util.ResourceBundle;
import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertTrue;
public class PropertyResourceUnitTest {
@Test
public void givenLocaleUsAsDefualt_whenGetBundleForLocalePlPl_thenItShouldContain3ButtonsAnd1Label() {
Locale.setDefault(Locale.US);
ResourceBundle bundle = ResourceBundle.getBundle("resourcebundle.resource", new Locale("pl", "PL"));
assertTrue(bundle.keySet()
.containsAll(Arrays.asList("backButton", "helloLabel", "cancelButton", "continueButton", "helloLabelNoEncoding")));
}
@Test
public void givenLocaleUsAsDefualt_whenGetBundleForLocaleFrFr_thenItShouldContainKeys1To3AndKey4() {
Locale.setDefault(Locale.US);
ResourceBundle bundle = ResourceBundle.getBundle("resourcebundle.resource", new Locale("fr", "FR"));
assertTrue(bundle.keySet()
.containsAll(Arrays.asList("deleteButton", "helloLabel", "cancelButton", "continueButton")));
}
@Test
public void givenLocaleChinaAsDefualt_whenGetBundleForLocaleFrFr_thenItShouldOnlyContainKeys1To3() {
Locale.setDefault(Locale.CHINA);
ResourceBundle bundle = ResourceBundle.getBundle("resourcebundle.resource", new Locale("fr", "FR"));
assertTrue(bundle.keySet()
.containsAll(Arrays.asList("continueButton", "helloLabel", "cancelButton")));
}
@Test
public void givenLocaleChinaAsDefualt_whenGetBundleForLocaleFrFrAndExampleControl_thenItShouldOnlyContainKey5() {
Locale.setDefault(Locale.CHINA);
ResourceBundle bundle = ResourceBundle.getBundle("resourcebundle.resource", new Locale("fr", "FR"), new ExampleControl());
assertTrue(bundle.keySet()
.containsAll(Arrays.asList("backButton", "helloLabel")));
}
@Test
public void givenValuesDifferentlyEncoded_whenGetBundleForLocalePlPl_thenItShouldContain3ButtonsAnd1Label() {
ResourceBundle bundle = ResourceBundle.getBundle("resourcebundle.resource", new Locale("pl", "PL"));
assertEquals(bundle.getString("helloLabel"), "cześć");
assertEquals(bundle.getString("helloLabelNoEncoding"), "czeÅ\u009BÄ\u0087");
}
}
core-java/src/test/java/com/baeldung/string/StringComparisonTest.java
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package com.baeldung.string;
import org.apache.commons.lang3.StringUtils;
import org.junit.Test;
import java.util.Objects;
import static org.assertj.core.api.Assertions.assertThat;
public class StringComparisonTest {
@Test
public void whenUsingComparisonOperator_ThenComparingStrings(){
String string1 = "using comparison operator";
String string2 = "using comparison operator";
String string3 = new String("using comparison operator");
assertThat(string1 == string2).isTrue();
assertThat(string1 == string3).isFalse();
}
@Test
public void whenUsingEqualsMethod_ThenComparingStrings(){
String string1 = "using equals method";
String string2 = "using equals method";
String string3 = "using EQUALS method";
String string4 = new String("using equals method");
assertThat(string1.equals(string2)).isTrue();
assertThat(string1.equals(string4)).isTrue();
assertThat(string1.equals(null)).isFalse();
assertThat(string1.equals(string3)).isFalse();
}
@Test
public void whenUsingEqualsIgnoreCase_ThenComparingStrings(){
String string1 = "using equals ignore case";
String string2 = "USING EQUALS IGNORE CASE";
assertThat(string1.equalsIgnoreCase(string2)).isTrue();
}
@Test
public void whenUsingCompareTo_ThenComparingStrings(){
String author = "author";
String book = "book";
String duplicateBook = "book";
assertThat(author.compareTo(book)).isEqualTo(-1);
assertThat(book.compareTo(author)).isEqualTo(1);
assertThat(duplicateBook.compareTo(book)).isEqualTo(0);
}
@Test
public void whenUsingCompareToIgnoreCase_ThenComparingStrings(){
String author = "Author";
String book = "book";
String duplicateBook = "BOOK";
assertThat(author.compareToIgnoreCase(book)).isEqualTo(-1);
assertThat(book.compareToIgnoreCase(author)).isEqualTo(1);
assertThat(duplicateBook.compareToIgnoreCase(book)).isEqualTo(0);
}
@Test
public void whenUsingObjectsEqualsMethod_ThenComparingStrings(){
String string1 = "using objects equals";
String string2 = "using objects equals";
String string3 = new String("using objects equals");
assertThat(Objects.equals(string1, string2)).isTrue();
assertThat(Objects.equals(string1, string3)).isTrue();
assertThat(Objects.equals(null, null)).isTrue();
assertThat(Objects.equals(null, string1)).isFalse();
}
@Test
public void whenUsingEqualsOfApacheCommons_ThenComparingStrings(){
assertThat(StringUtils.equals(null, null)).isTrue();
assertThat(StringUtils.equals(null, "equals method")).isFalse();
assertThat(StringUtils.equals("equals method", "equals method")).isTrue();
assertThat(StringUtils.equals("equals method", "EQUALS METHOD")).isFalse();
}
@Test
public void whenUsingEqualsIgnoreCaseOfApacheCommons_ThenComparingStrings(){
assertThat(StringUtils.equalsIgnoreCase(null, null)).isTrue();
assertThat(StringUtils.equalsIgnoreCase(null, "equals method")).isFalse();
assertThat(StringUtils.equalsIgnoreCase("equals method", "equals method")).isTrue();
assertThat(StringUtils.equalsIgnoreCase("equals method", "EQUALS METHOD")).isTrue();
}
@Test
public void whenUsingEqualsAnyOf_ThenComparingStrings(){
assertThat(StringUtils.equalsAny(null, null, null)).isTrue();
assertThat(StringUtils.equalsAny("equals any", "equals any", "any")).isTrue();
assertThat(StringUtils.equalsAny("equals any", null, "equals any")).isTrue();
assertThat(StringUtils.equalsAny(null, "equals", "any")).isFalse();
assertThat(StringUtils.equalsAny("equals any", "EQUALS ANY", "ANY")).isFalse();
}
@Test
public void whenUsingEqualsAnyIgnoreCase_ThenComparingStrings(){
assertThat(StringUtils.equalsAnyIgnoreCase(null, null, null)).isTrue();
assertThat(StringUtils.equalsAnyIgnoreCase("equals any", "equals any", "any")).isTrue();
assertThat(StringUtils.equalsAnyIgnoreCase("equals any", null, "equals any")).isTrue();
assertThat(StringUtils.equalsAnyIgnoreCase(null, "equals", "any")).isFalse();
assertThat(StringUtils.equalsAnyIgnoreCase(
"equals any ignore case", "EQUALS ANY IGNORE CASE", "any")).isTrue();
}
@Test
public void whenUsingCompare_thenComparingStringsWithNulls(){
assertThat(StringUtils.compare(null, null)).isEqualTo(0);
assertThat(StringUtils.compare(null, "abc")).isEqualTo(-1);
assertThat(StringUtils.compare("abc", "bbc")).isEqualTo(-1);
assertThat(StringUtils.compare("bbc", "abc")).isEqualTo(1);
assertThat(StringUtils.compare("abc", "abc")).isEqualTo(0);
}
@Test
public void whenUsingCompareIgnoreCase_ThenComparingStringsWithNulls(){
assertThat(StringUtils.compareIgnoreCase(null, null)).isEqualTo(0);
assertThat(StringUtils.compareIgnoreCase(null, "abc")).isEqualTo(-1);
assertThat(StringUtils.compareIgnoreCase("Abc", "bbc")).isEqualTo(-1);
assertThat(StringUtils.compareIgnoreCase("bbc", "ABC")).isEqualTo(1);
assertThat(StringUtils.compareIgnoreCase("abc", "ABC")).isEqualTo(0);
}
@Test
public void whenUsingCompareWithNullIsLessOption_ThenComparingStrings(){
assertThat(StringUtils.compare(null, "abc", true)).isEqualTo(-1);
assertThat(StringUtils.compare(null, "abc", false)).isEqualTo(1);
}
}
core-java/src/test/java/com/baeldung/system/WhenDetectingOSTest.java
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package com.baeldung.system;
import org.junit.Assert;
import org.junit.Ignore;
import org.junit.Test;
@Ignore
public class WhenDetectingOSTest {
private DetectOS os = new DetectOS();
@Test
public void whenUsingSystemProperty_shouldReturnOS() {
String expected = "Windows 10";
String actual = os.getOperatingSystem();
Assert.assertEquals(expected, actual);
}
@Test
public void whenUsingSystemUtils_shouldReturnOS() {
String expected = "Windows 10";
String actual = os.getOperatingSystemSystemUtils();
Assert.assertEquals(expected, actual);
}
}
core-java/src/test/resources/copyTest/dest/readme.txt
-2
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@@ -1,2 +0,0 @@
files will be copied here and then deleted
remove `file.delete()` to see the files here
core-java/src/test/resources/copyTest/src/test_apache.txt
-1
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@@ -1 +0,0 @@
apache
core-java/src/test/resources/copyTest/src/test_channel.txt
-1
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@@ -1 +0,0 @@
channel
core-java/src/test/resources/copyTest/src/test_files.txt
-1
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@@ -1 +0,0 @@
files
core-java/src/test/resources/copyTest/src/test_stream.txt
-1
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@@ -1 +0,0 @@
stream
core-java/src/test/resources/file.txt
-1
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@@ -1 +0,0 @@
baeldung.com
core-java/src/test/resources/fileToRead.txt
-1
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@@ -1 +0,0 @@
This is a content of the file
core-java/src/test/resources/fileToWriteTo.txt
View File
core-java/src/test/resources/testFolder/sample_file_1.in
-1
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@@ -1 +0,0 @@
Hello world
core-java/src/test/resources/testFolder/sample_file_2.in
-1
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@@ -1 +0,0 @@
Hello world !