[JAVA-14174] Renamed paterns to paterns-module (#12718)

* [JAVA-14174] Renamed paterns to paterns-module * [JAVA-14174] naming fixes Co-authored-by: panagiotiskakos <[email protected]>
2022-09-19 12:14:14 +05:30
parent 74dcaa0935
commit 63a9bfbad9
518 changed files with 32 additions and 32 deletions
@@ -0,0 +1,10 @@
+### Relevant Articles:
+- [Singletons in Java](https://www.baeldung.com/java-singleton)
+- [Introduction to Creational Design Patterns](https://www.baeldung.com/creational-design-patterns)
+- [Abstract Factory Pattern in Java](https://www.baeldung.com/java-abstract-factory-pattern)
+- [Flyweight Pattern in Java](https://www.baeldung.com/java-flyweight)
+- [Double-Checked Locking with Singleton](https://www.baeldung.com/java-singleton-double-checked-locking)
+- [Java Constructors vs Static Factory Methods](https://www.baeldung.com/java-constructors-vs-static-factory-methods)
+- [Automatic Generation of the Builder Pattern with FreeBuilder](https://www.baeldung.com/java-builder-pattern-freebuilder)
+- [How to Replace Many if Statements in Java](https://www.baeldung.com/java-replace-if-statements)
+- [Prototype Pattern in Java](https://www.baeldung.com/java-pattern-prototype)
@@ -0,0 +1,36 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+    <artifactId>design-patterns-creational</artifactId>
+    <version>1.0</version>
+    <name>design-patterns-creational</name>
+    <packaging>jar</packaging>
+
+    <parent>
+        <groupId>com.baeldung</groupId>
+        <artifactId>patterns-modules</artifactId>
+        <version>1.0.0-SNAPSHOT</version>
+    </parent>
+
+    <dependencies>
+        <dependency>
+            <groupId>org.inferred</groupId>
+            <artifactId>freebuilder</artifactId>
+            <version>${freebuilder.version}</version>
+            <optional>true</optional>
+        </dependency>
+        <dependency>
+            <groupId>com.google.code.findbugs</groupId>
+            <artifactId>jsr305</artifactId>
+            <version>${javax.annotations.version}</version>
+        </dependency>
+    </dependencies>
+
+    <properties>
+        <freebuilder.version>2.4.1</freebuilder.version>
+        <javax.annotations.version>3.0.2</javax.annotations.version>
+    </properties>
+
+</project>
@@ -0,0 +1,12 @@
+package com.baeldung.constructorsstaticfactorymethods.application;
+
+import com.baeldung.constructorsstaticfactorymethods.entities.User;
+ 
+public class Application {
+
+    public static void main(String[] args) {
+        User user1 = User.createWithDefaultCountry("John", "[email protected]");
+        User user2 = User.createWithLoggedInstantiationTime("John", "[email protected]", "Argentina");
+        User user3 = User.getSingletonInstance("John", "[email protected]", "Argentina");
+    }
+}
@@ -0,0 +1,56 @@
+package com.baeldung.constructorsstaticfactorymethods.entities;
+
+import java.time.LocalTime;
+import java.util.logging.ConsoleHandler;
+import java.util.logging.Level;
+import java.util.logging.Logger;
+import java.util.logging.SimpleFormatter;
+
+public class User {
+
+    private static volatile User instance = null;
+    private static final Logger LOGGER = Logger.getLogger(User.class.getName());
+    private final String name;
+    private final String email;
+    private final String country;
+    
+    public static User createWithDefaultCountry(String name, String email) {
+        return new User(name, email, "Argentina");
+    }
+
+    public static User createWithLoggedInstantiationTime(String name, String email, String country) {
+        LOGGER.log(Level.INFO, "Creating User instance at : {0}", LocalTime.now());
+
+        return new User(name, email, country);
+    }
+
+    public static User getSingletonInstance(String name, String email, String country) {
+        if (instance == null) {
+            synchronized (User.class) {
+                if (instance == null) {
+                    instance = new User(name, email, country);
+                }
+            }
+        }
+        return instance;
+
+    }
+
+    private User(String name, String email, String country) {
+        this.name = name;
+        this.email = email;
+        this.country = country;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public String getEmail() {
+        return email;
+    }
+
+    public String getCountry() {
+        return country;
+    }
+}
@@ -0,0 +1,5 @@
+package com.baeldung.creational.abstractfactory;
+
+public interface AbstractFactory<T> {
+    T create(String type) ;
+}
@@ -0,0 +1,18 @@
+package com.baeldung.creational.abstractfactory;
+
+public class AbstractPatternDriver {
+    public static void main(String[] args) {
+        AbstractFactory abstractFactory;
+        
+        //creating a brown toy dog
+        abstractFactory = FactoryProvider.getFactory("Toy");
+        Animal toy =(Animal) abstractFactory.create("Dog");
+        
+        abstractFactory = FactoryProvider.getFactory("Color");
+        Color color =(Color) abstractFactory.create("Brown");
+        
+        String result = "A " + toy.getType() + " with " + color.getColor() + " color " + toy.makeSound();
+        
+        System.out.println(result);
+    }
+}
@@ -0,0 +1,6 @@
+package com.baeldung.creational.abstractfactory;
+
+public interface Animal {
+    String getType();
+    String makeSound();
+}
@@ -0,0 +1,16 @@
+package com.baeldung.creational.abstractfactory;
+
+public class AnimalFactory implements AbstractFactory<Animal> {
+
+    @Override
+    public Animal create(String animalType) {
+        if ("Dog".equalsIgnoreCase(animalType)) {
+            return new Dog();
+        } else if ("Duck".equalsIgnoreCase(animalType)) {
+            return new Duck();
+        }
+
+        return null;
+    }
+
+}
@@ -0,0 +1,10 @@
+package com.baeldung.creational.abstractfactory;
+
+public class Brown implements Color {
+
+    @Override
+    public String getColor() {
+        return "brown";
+    }
+
+}
@@ -0,0 +1,5 @@
+package com.baeldung.creational.abstractfactory;
+
+public interface Color {
+    String getColor();
+}
@@ -0,0 +1,16 @@
+package com.baeldung.creational.abstractfactory;
+
+public class ColorFactory implements AbstractFactory<Color> {
+
+    @Override
+    public Color create(String colorType) {
+        if ("Brown".equalsIgnoreCase(colorType)) {
+            return new Brown();
+        } else if ("White".equalsIgnoreCase(colorType)) {
+            return new White();
+        }
+
+        return null;
+    }
+
+}
@@ -0,0 +1,15 @@
+package com.baeldung.creational.abstractfactory;
+
+public class Dog implements Animal {
+
+    @Override
+    public String getType() {
+        return "Dog";
+    }
+
+    @Override
+    public String makeSound() {
+        return "Barks";
+    }
+
+}
@@ -0,0 +1,15 @@
+package com.baeldung.creational.abstractfactory;
+
+public class Duck implements Animal {
+
+    @Override
+    public String getType() {
+        return "Duck";
+    }
+
+    @Override
+    public String makeSound() {
+        return "Squeks";
+    }
+
+}
@@ -0,0 +1,15 @@
+package com.baeldung.creational.abstractfactory;
+
+public class FactoryProvider {
+    public static AbstractFactory getFactory(String choice){
+        
+        if("Toy".equalsIgnoreCase(choice)){
+            return new AnimalFactory();
+        }
+        else if("Color".equalsIgnoreCase(choice)){
+            return new ColorFactory();
+        }
+        
+        return null;
+    }
+}
@@ -0,0 +1,10 @@
+package com.baeldung.creational.abstractfactory;
+
+public class White implements Color {
+
+    @Override
+    public String getColor() {
+        return "White";
+    }
+
+}
@@ -0,0 +1,64 @@
+package com.baeldung.creational.builder;
+
+public class BankAccount {
+    private String name;
+    private String accountNumber;
+    private String email;
+    private boolean newsletter;
+
+    //The constructor that takes a builder from which it will create object
+    //the access to this is only provided to builder
+    private BankAccount(BankAccountBuilder builder) {
+        this.name = builder.name;
+        this.accountNumber = builder.accountNumber;
+        this.email = builder.email;
+        this.newsletter = builder.newsletter;
+    }
+    
+    public static class BankAccountBuilder {
+        private String name;
+        private String accountNumber;
+        private String email;
+        private boolean newsletter;
+        
+        //All Mandatory parameters goes with this constructor
+        public BankAccountBuilder(String name, String accountNumber) {
+            this.name = name;
+            this.accountNumber = accountNumber;
+        }
+
+        //setters for optional parameters which returns this same builder
+        //to support fluent design
+        public BankAccountBuilder withEmail(String email) {
+            this.email = email;
+            return this;
+        }
+
+        public BankAccountBuilder wantNewsletter(boolean newsletter) {
+            this.newsletter = newsletter;
+            return this;
+        }
+        
+        //the actual build method that prepares and returns a BankAccount object
+        public BankAccount build() {
+            return new BankAccount(this);
+        }
+    }
+
+    //getters
+    public String getName() {
+        return name;
+    }
+
+    public String getAccountNumber() {
+        return accountNumber;
+    }
+
+    public String getEmail() {
+        return email;
+    }
+
+    public boolean isNewsletter() {
+        return newsletter;
+    }
+}
@@ -0,0 +1,16 @@
+package com.baeldung.creational.builder;
+
+public class BuilderPatternDriver {
+    public static void main(String[] args) {
+        BankAccount newAccount = new BankAccount
+          .BankAccountBuilder("Jon", "22738022275")
+          .withEmail("[email protected]")
+          .wantNewsletter(true)
+          .build();
+
+        System.out.println("Name: " + newAccount.getName());
+        System.out.println("AccountNumber:" + newAccount.getAccountNumber());
+        System.out.println("Email: " + newAccount.getEmail());
+        System.out.println("Want News letter?: " + newAccount.isNewsletter());
+    }
+}
@@ -0,0 +1,16 @@
+package com.baeldung.creational.factory;
+
+public class FactoryDriver {
+    public static void main(String[] args) {
+        Polygon p;
+        PolygonFactory factory = new PolygonFactory();
+        
+        //get the shape which has 4 sides
+        p = factory.getPolygon(4);
+        System.out.println("The shape with 4 sides is a " + p.getType());
+        
+        //get the shape which has 4 sides
+        p = factory.getPolygon(8);
+        System.out.println("The shape with 8 sides is a " + p.getType());
+    }
+}
@@ -0,0 +1,10 @@
+package com.baeldung.creational.factory;
+
+public class Heptagon implements Polygon {
+
+    @Override
+    public String getType() {
+        return "Heptagon";
+    }
+
+}
@@ -0,0 +1,10 @@
+package com.baeldung.creational.factory;
+
+public class Octagon implements Polygon {
+
+    @Override
+    public String getType() {
+        return "Octagon";
+    }
+
+}
@@ -0,0 +1,10 @@
+package com.baeldung.creational.factory;
+
+public class Pentagon implements Polygon {
+
+    @Override
+    public String getType() {
+        return "Pentagon";
+    }
+
+}
@@ -0,0 +1,5 @@
+package com.baeldung.creational.factory;
+
+public interface Polygon {
+    String getType();
+}
@@ -0,0 +1,22 @@
+package com.baeldung.creational.factory;
+
+public class PolygonFactory {
+    public Polygon getPolygon(int numberOfSides) {
+        if(numberOfSides == 3) {
+            return new Triangle();
+        }
+        if(numberOfSides == 4) {
+            return new Square();
+        }
+        if(numberOfSides == 5) {
+            return new Pentagon();
+        }
+        if(numberOfSides == 7) {
+            return new Heptagon();
+        }
+        else if(numberOfSides == 8) {
+            return new Octagon();
+        }
+        return null;
+    }
+}
@@ -0,0 +1,10 @@
+package com.baeldung.creational.factory;
+
+public class Square implements Polygon {
+
+    @Override
+    public String getType() {
+        return "Square";
+    }
+
+}
@@ -0,0 +1,10 @@
+package com.baeldung.creational.factory;
+
+public class Triangle implements Polygon {
+
+    @Override
+    public String getType() {
+        return "Triangle";
+    }
+
+}
@@ -0,0 +1,13 @@
+package com.baeldung.creational.singleton;
+
+public class Singleton  {    
+    private Singleton() {}
+    
+    private static class SingletonHolder {    
+        public static final Singleton instance = new Singleton();
+    }    
+
+    public static Singleton getInstance() {    
+        return SingletonHolder.instance;    
+    }    
+}
@@ -0,0 +1,8 @@
+package com.baeldung.creational.singleton;
+
+public class SingletonDriver {
+    public static void main(String[] args) {
+        Singleton instance = Singleton.getInstance();
+        System.out.println(instance.toString());
+    }
+}
@@ -0,0 +1,82 @@
+package com.baeldung.flyweight;
+
+import java.awt.Color;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * Represents a car. This class is immutable.
+ * 
+ * @author Donato Rimenti
+ */
+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.flyweight.Vehicle#start()
+	 */
+	@Override
+	public void start() {
+		LOG.info("Car is starting!");
+		engine.start();
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * 
+	 * @see com.baeldung.flyweight.Vehicle#stop()
+	 */
+	@Override
+	public void stop() {
+		LOG.info("Car is stopping!");
+		engine.stop();
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * 
+	 * @see com.baeldung.flyweight.Vehicle#getColor()
+	 */
+	@Override
+	public Color getColor() {
+		return this.color;
+	}
+
+}
@@ -0,0 +1,31 @@
+package com.baeldung.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!");
+	}
+}
@@ -0,0 +1,29 @@
+package com.baeldung.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();
+
+}
--- a/Show More
+++ b/Show More