Merge branch 'eugenp:master' into master

2023-04-26 17:02:40 -05:00
parent 1628c013c6 e3cc8abadb
commit bf1e9aa588
1040 changed files with 14610 additions and 2156 deletions
@@ -1,3 +1,4 @@
 ## Relevant Articles
 - [Record Patterns in Java 19](https://www.baeldung.com/java-19-record-patterns)
 - [Structured Concurrency in Java 19](https://www.baeldung.com/java-structured-concurrency)
+- [Possible Root Causes for High CPU Usage in Java](https://www.baeldung.com/java-high-cpu-usage-causes)
@@ -11,4 +11,6 @@ This module contains articles about Java 8 core features
 - [Convert Between Byte Array and UUID in Java](https://www.baeldung.com/java-byte-array-to-uuid)
 - [Create a Simple “Rock-Paper-Scissors” Game in Java](https://www.baeldung.com/java-rock-paper-scissors)
 - [VarArgs vs Array Input Parameters in Java](https://www.baeldung.com/varargs-vs-array)
+- [Lambda Expression vs. Anonymous Inner Class](https://www.baeldung.com/java-lambdas-vs-anonymous-class)
+- [Java Helper vs. Utility Classes](https://www.baeldung.com/java-helper-vs-utility-classes)
 - [[<-- Prev]](/core-java-modules/core-java-8)
@@ -2,4 +2,5 @@

 - [Generating Random Dates in Java](https://www.baeldung.com/java-random-dates)
 - [Creating a LocalDate with Values in Java](https://www.baeldung.com/java-creating-localdate-with-values)
- [[<-- Prev]](/core-java-modules/core-java-datetime-java8-1)
+- [Parsing Date Strings with Varying Formats](https://www.baeldung.com/java-parsing-dates-many-formats)
+- [[<-- Prev]](/core-java-modules/core-java-datetime-java8-1)
@@ -0,0 +1,20 @@
+package com.baeldung.parsingDates;
+
+import java.util.Arrays;
+import java.util.List;
+import org.joda.time.LocalDate;
+import org.joda.time.format.DateTimeFormat;
+
+public class SimpleDateTimeFormat {
+
+    public static LocalDate parseDate(String date) {
+        List<String> patternList = Arrays.asList("MM/dd/yyyy", "dd.MM.yyyy", "yyyy-MM-dd");
+        for (String pattern : patternList) {
+            try {
+                return DateTimeFormat.forPattern(pattern).parseLocalDate(date);
+            } catch (IllegalArgumentException e) {
+            }
+        }
+        return null;
+    }
+}
@@ -0,0 +1,17 @@
+package com.baeldung.parsingDates;
+
+import java.time.LocalDate;
+import java.time.format.DateTimeFormatter;
+import java.time.format.DateTimeFormatterBuilder;
+
+public class SimpleDateTimeFormater {
+
+    public static LocalDate parseDate(String date) {
+        DateTimeFormatterBuilder dateTimeFormatterBuilder = new DateTimeFormatterBuilder()
+                .append(DateTimeFormatter.ofPattern("[MM/dd/yyyy]" + "[dd-MM-yyyy]" + "[yyyy-MM-dd]"));
+
+        DateTimeFormatter dateTimeFormatter = dateTimeFormatterBuilder.toFormatter();
+
+        return LocalDate.parse(date, dateTimeFormatter);
+    }
+}
@@ -0,0 +1,18 @@
+package com.baeldung.parsingDates;
+
+import java.text.ParseException;
+import java.util.Date;
+import org.apache.commons.lang3.time.DateUtils;
+
+public class SimpleDateUtils {
+
+    public static Date parseDate(String date) {
+        try {
+            return DateUtils.parseDateStrictly(date,
+                    new String[]{"yyyy/MM/dd", "dd/MM/yyyy", "yyyy-MM-dd"});
+        } catch (ParseException ex) {
+            return null;
+        }
+    }
+
+}
@@ -0,0 +1,19 @@
+package com.baeldung.parsingDates;
+
+import java.text.ParseException;
+import java.text.SimpleDateFormat;
+import java.util.Date;
+import java.util.List;
+
+public class SimpleParseDate {
+
+    public Date parseDate(String dateString, List<String> formatStrings) {
+        for (String formatString : formatStrings) {
+            try {
+                return new SimpleDateFormat(formatString).parse(dateString);
+            } catch (ParseException e) {
+            }
+        }
+        return null;
+    }
+}
@@ -0,0 +1,43 @@
+package com.baeldung.parsingDates;
+
+import com.baeldung.parsingDates.SimpleDateTimeFormat;
+import com.baeldung.parsingDates.SimpleDateTimeFormater;
+import com.baeldung.parsingDates.SimpleDateUtils;
+import com.baeldung.parsingDates.SimpleParseDate;
+import java.time.format.DateTimeParseException;
+import java.util.Arrays;
+import org.junit.*;
+import static org.junit.Assert.*;
+import org.joda.time.LocalDate;
+
+public class SimpleParseDateUnitTest {
+
+    @Test
+    public void whenInvalidInput_thenGettingUnexpectedResult() {
+        SimpleParseDate simpleParseDate = new SimpleParseDate();
+        String date = "2022-40-40";
+        assertEquals("Sat May 10 00:00:00 UTC 2025", simpleParseDate.parseDate(date, Arrays.asList("MM/dd/yyyy", "dd.MM.yyyy", "yyyy-MM-dd")).toString());
+    }
+
+    @Test
+    public void whenInvalidDate_thenAssertThrows() {
+        SimpleDateTimeFormater simpleDateTimeFormater = new SimpleDateTimeFormater();
+        assertEquals(java.time.LocalDate.parse("2022-12-04"), simpleDateTimeFormater.parseDate("2022-12-04"));
+        assertThrows(DateTimeParseException.class, () -> simpleDateTimeFormater.parseDate("2022-13-04"));
+    }
+
+    @Test
+    public void whenDateIsCorrect_thenParseCorrect() {
+        SimpleDateUtils simpleDateUtils = new SimpleDateUtils();
+        assertNull(simpleDateUtils.parseDate("53/10/2014"));
+        assertEquals("Wed Sep 10 00:00:00 UTC 2014", simpleDateUtils.parseDate("10/09/2014").toString());
+    }
+
+    @Test
+    public void whenDateIsCorrect_thenResultCorrect() {
+        SimpleDateTimeFormat simpleDateTimeFormat = new SimpleDateTimeFormat();
+        assertNull(simpleDateTimeFormat.parseDate("53/10/2014"));
+        assertEquals(LocalDate.parse("2014-10-10"), simpleDateTimeFormat.parseDate("2014-10-10"));
+    }
+
+}
@@ -8,5 +8,5 @@ This module contains articles about Project Jigsaw and the Java Platform Module
 - [A Guide to Java 9 Modularity](https://www.baeldung.com/java-9-modularity)
 - [Java 9 java.lang.Module API](https://www.baeldung.com/java-9-module-api)
 - [Java 9 Illegal Reflective Access Warning](https://www.baeldung.com/java-illegal-reflective-access)
-
+- [Java Modularity and Unit Testing](https://www.baeldung.com/java-modularity-unit-testing)

@@ -0,0 +1,2 @@
+#!/usr/bin/env bash
+javac -d mods/com.baeldung.library.core $(find library-core/src/main -name "*.java")
@@ -0,0 +1,10 @@
+#!/usr/bin/env bash
+javac --class-path outDir/library-core/:\
+libs/junit-jupiter-engine-5.9.2.jar:\
+libs/junit-platform-engine-1.9.2.jar:\
+libs/apiguardian-api-1.1.2.jar:\
+libs/junit-jupiter-params-5.9.2.jar:\
+libs/junit-jupiter-api-5.9.2.jar:\
+libs/opentest4j-1.2.0.jar:\
+libs/junit-platform-commons-1.9.2.jar \
+-d outDir/library-test library-core/src/test/java/com/baeldung/library/core/LibraryUnitTest.java
@@ -0,0 +1,13 @@
+#!/usr/bin/env bash
+javac --class-path libs/junit-jupiter-engine-5.9.2.jar:\
+libs/junit-platform-engine-1.9.2.jar:\
+libs/apiguardian-api-1.1.2.jar:\
+libs/junit-jupiter-params-5.9.2.jar:\
+libs/junit-jupiter-api-5.9.2.jar:\
+libs/opentest4j-1.2.0.jar:\
+libs/junit-platform-commons-1.9.2.jar \
+-d outDir/library-core \
+library-core/src/main/java/com/baeldung/library/core/Book.java \
+library-core/src/main/java/com/baeldung/library/core/Library.java \
+library-core/src/main/java/com/baeldung/library/core/Main.java \
+library-core/src/test/java/com/baeldung/library/core/LibraryUnitTest.java
@@ -0,0 +1,12 @@
+#!/usr/bin/env bash
+javac --class-path libs/junit-jupiter-engine-5.9.2.jar:\
+libs/junit-platform-engine-1.9.2.jar:\
+libs/apiguardian-api-1.1.2.jar:\
+libs/junit-jupiter-params-5.9.2.jar:\
+libs/junit-jupiter-api-5.9.2.jar:\
+libs/opentest4j-1.2.0.jar:\
+libs/junit-platform-commons-1.9.2.jar \
+-d outDir/library-core \
+library-core/src/main/java/com/baeldung/library/core/Book.java \
+library-core/src/main/java/com/baeldung/library/core/Library.java \
+library-core/src/main/java/com/baeldung/library/core/Main.java
@@ -0,0 +1,2 @@
+#!/usr/bin/env bash
+javac --module-path mods:libs -d mods/com.baeldung.library.test $(find library-test/src/test -name "*.java")
@@ -0,0 +1,10 @@
+#!/usr/bin/env bash
+wget -P libs/ https://repo1.maven.org/maven2/org/apiguardian/apiguardian-api/1.1.2/apiguardian-api-1.1.2.jar /
+wget -P libs/ https://repo1.maven.org/maven2/org/opentest4j/opentest4j/1.2.0/opentest4j-1.2.0.jar /
+wget -P libs/ https://repo1.maven.org/maven2/org/junit/platform/junit-platform-commons/1.9.2/junit-platform-commons-1.9.2.jar /
+wget -P libs/ https://repo1.maven.org/maven2/org/junit/platform/junit-platform-engine/1.9.2/junit-platform-engine-1.9.2.jar /
+wget -P libs/ https://repo1.maven.org/maven2/org/junit/platform/junit-platform-reporting/1.9.2/junit-platform-reporting-1.9.2.jar /
+wget -P libs/ https://repo1.maven.org/maven2/org/junit/platform/junit-platform-console/1.9.2/junit-platform-console-1.9.2.jar /
+wget -P libs/ https://repo1.maven.org/maven2/org/junit/platform/junit-platform-launcher/1.9.2/junit-platform-launcher-1.9.2.jar /
+wget -P libs/ https://repo1.maven.org/maven2/org/junit/jupiter/junit-jupiter-engine/5.9.2/junit-jupiter-engine-5.9.2.jar /
+wget -P libs/ https://repo1.maven.org/maven2/org/junit/jupiter/junit-jupiter-params/5.9.2/junit-jupiter-params-5.9.2.jar
@@ -0,0 +1,55 @@
+<?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>
+  <parent>
+    <groupId>com.baeldung</groupId>
+    <artifactId>core-java-9-jigsaw</artifactId>
+    <version>0.2-SNAPSHOT</version>
+  </parent>
+
+  <artifactId>library-core</artifactId>
+
+  <properties>
+    <maven.compiler.source>19</maven.compiler.source>
+    <maven.compiler.target>19</maven.compiler.target>
+    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
+  </properties>
+
+  <dependencies>
+    <dependency>
+      <groupId>org.junit.jupiter</groupId>
+      <artifactId>junit-jupiter-api</artifactId>
+      <version>5.9.2</version>
+      <scope>test</scope>
+    </dependency>
+    <dependency>
+      <groupId>org.junit.jupiter</groupId>
+      <artifactId>junit-jupiter-engine</artifactId>
+      <version>5.9.2</version>
+      <scope>test</scope>
+    </dependency>
+  </dependencies>
+
+  <build>
+    <plugins>
+      <plugin>
+        <groupId>org.apache.maven.plugins</groupId>
+        <artifactId>maven-compiler-plugin</artifactId>
+        <version>3.8.1</version>
+        <configuration>
+          <release>9</release>
+        </configuration>
+      </plugin>
+      <plugin>
+        <groupId>org.apache.maven.plugins</groupId>
+        <artifactId>maven-surefire-plugin</artifactId>
+        <version>3.0.0-M5</version>
+        <configuration>
+          <useModulePath>false</useModulePath>
+        </configuration>
+      </plugin>
+    </plugins>
+  </build>
+</project>
@@ -0,0 +1,52 @@
+package com.baeldung.library.core;
+
+import java.util.Objects;
+
+public class Book {
+
+    private String title;
+    private String author;
+
+    public Book(String title, String author) {
+        this.title = title;
+        this.author = author;
+    }
+
+    public String getTitle() {
+        return title;
+    }
+
+    public String getAuthor() {
+        return author;
+    }
+
+
+    @Override
+    public String toString() {
+        return "Book [title=" + title + ", author=" + author + "]";
+    }
+
+    @Override
+    public boolean equals(final Object o) {
+        if (this == o) {
+            return true;
+        }
+        if (o == null || getClass() != o.getClass()) {
+            return false;
+        }
+
+        final Book book = (Book) o;
+
+        if (!Objects.equals(title, book.title)) {
+            return false;
+        }
+        return Objects.equals(author, book.author);
+    }
+
+    @Override
+    public int hashCode() {
+        int result = title != null ? title.hashCode() : 0;
+        result = 31 * result + (author != null ? author.hashCode() : 0);
+        return result;
+    }
+}
@@ -0,0 +1,25 @@
+package com.baeldung.library.core;
+
+import java.util.ArrayList;
+import java.util.List;
+
+public class Library {
+
+    private List<Book> books = new ArrayList<>();
+
+    public void addBook(Book book) {
+        books.add(book);
+    }
+
+    public List<Book> getBooks() {
+        return books;
+    }
+
+    void removeBook(Book book) {
+        books.remove(book);
+    }
+
+    protected void removeBookByAuthor(String author) {
+        books.removeIf(book -> book.getAuthor().equals(author));
+    }
+}
@@ -0,0 +1,16 @@
+package com.baeldung.library.core;
+
+public class Main {
+
+    public static void main(String[] args) {
+        Library library = new Library();
+        library.addBook(new Book("The Lord of the Rings", "J.R.R. Tolkien"));
+        library.addBook(new Book("The Hobbit", "J.R.R. Tolkien"));
+        library.addBook(new Book("The Silmarillion", "J.R.R. Tolkien"));
+        library.addBook(new Book("The Chronicles of Narnia", "C.S. Lewis"));
+        library.addBook(new Book("The Lion, the Witch and the Wardrobe", "C.S. Lewis"));
+        System.out.println("Welcome to our library!");
+        System.out.println("We have the following books:");
+        library.getBooks().forEach(System.out::println);
+    }
+}
@@ -0,0 +1,3 @@
+module com.baeldung.library.core {
+    exports com.baeldung.library.core;
+}
@@ -0,0 +1,47 @@
+package com.baeldung.library.core;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+import org.junit.jupiter.api.Test;
+
+class LibraryUnitTest {
+
+    @Test
+    void givenEmptyLibrary_whenAddABook_thenLibraryHasOneBook() {
+        Library library = new Library();
+        Book theLordOfTheRings = new Book("The Lord of the Rings", "J.R.R. Tolkien");
+        library.addBook(theLordOfTheRings);
+        int expected = 1;
+        int actual = library.getBooks().size();
+        assertEquals(expected, actual);
+    }
+
+    @Test
+    void givenTheLibraryWithABook_whenRemoveABook_thenLibraryIsEmpty() {
+        Library library = new Library();
+        Book theLordOfTheRings = new Book("The Lord of the Rings", "J.R.R. Tolkien");
+        library.addBook(theLordOfTheRings);
+        library.removeBook(theLordOfTheRings);
+        int expected = 0;
+        int actual = library.getBooks().size();
+        assertEquals(expected, actual);
+    }
+
+    @Test
+    void givenTheLibraryWithSeveralBook_whenRemoveABookByAuthor_thenLibraryHasNoBooksByTheAuthor() {
+        Library library = new Library();
+        Book theLordOfTheRings = new Book("The Lord of the Rings", "J.R.R. Tolkien");
+        Book theHobbit = new Book("The Hobbit", "J.R.R. Tolkien");
+        Book theSilmarillion = new Book("The Silmarillion", "J.R.R. Tolkien");
+        Book theHungerGames = new Book("The Hunger Games", "Suzanne Collins");
+        library.addBook(theLordOfTheRings);
+        library.addBook(theHobbit);
+        library.addBook(theSilmarillion);
+        library.addBook(theHungerGames);
+        library.removeBookByAuthor("J.R.R. Tolkien");
+        int expected = 1;
+        int actual = library.getBooks().size();
+        assertEquals(expected, actual);
+    }
+
+}
@@ -0,0 +1,53 @@
+package com.baeldung.library.test;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+import com.baeldung.library.core.Book;
+import com.baeldung.library.core.Library;
+import java.lang.reflect.InvocationTargetException;
+import java.lang.reflect.Method;
+import org.junit.jupiter.api.Test;
+
+class LibraryUnitTest {
+
+    @Test
+    void givenEmptyLibrary_whenAddABook_thenLibraryHasOneBook() {
+        Library library = new Library();
+        Book theLordOfTheRings = new Book("The Lord of the Rings", "J.R.R. Tolkien");
+        library.addBook(theLordOfTheRings);
+        int expected = 1;
+        int actual = library.getBooks().size();
+        assertEquals(expected, actual);
+    }
+
+    @Test
+    void givenTheLibraryWithABook_whenRemoveABook_thenLibraryIsEmpty()
+        throws NoSuchMethodException, InvocationTargetException, IllegalAccessException {
+        Library library = new Library();
+        Book theLordOfTheRings = new Book("The Lord of the Rings", "J.R.R. Tolkien");
+        library.addBook(theLordOfTheRings);
+        Method removeBook = Library.class.getDeclaredMethod("removeBook", Book.class);
+        removeBook.setAccessible(true);
+        removeBook.invoke(library, theLordOfTheRings);
+        int expected = 0;
+        int actual = library.getBooks().size();
+        assertEquals(expected, actual);
+    }
+@Test
+void givenTheLibraryWithSeveralBook_whenRemoveABookByAuthor_thenLibraryHasNoBooksByTheAuthor() {
+    TestLibrary library = new TestLibrary();
+    Book theLordOfTheRings = new Book("The Lord of the Rings", "J.R.R. Tolkien");
+    Book theHobbit = new Book("The Hobbit", "J.R.R. Tolkien");
+    Book theSilmarillion = new Book("The Silmarillion", "J.R.R. Tolkien");
+    Book theHungerGames = new Book("The Hunger Games", "Suzanne Collins");
+    library.addBook(theLordOfTheRings);
+    library.addBook(theHobbit);
+    library.addBook(theSilmarillion);
+    library.addBook(theHungerGames);
+    library.removeBookByAuthor("J.R.R. Tolkien");
+    int expected = 1;
+    int actual = library.getBooks().size();
+    assertEquals(expected, actual);
+}
+
+}
@@ -0,0 +1,10 @@
+package com.baeldung.library.test;
+
+import com.baeldung.library.core.Library;
+
+public class TestLibrary extends Library {
+    @Override
+    public void removeBookByAuthor(final String author) {
+        super.removeBookByAuthor(author);
+    }
+}
@@ -0,0 +1,5 @@
+module com.baeldung.library.test {
+    requires com.baeldung.library.core;
+    requires org.junit.jupiter.api;
+    opens com.baeldung.library.test to org.junit.platform.commons;
+}
@@ -5,6 +5,10 @@
    <modelVersion>4.0.0</modelVersion>
    <artifactId>core-java-9-jigsaw</artifactId>
    <name>core-java-9-jigsaw</name>
+    <packaging>pom</packaging>
+    <modules>
+        <module>library-core</module>
+    </modules>

    <parent>
        <groupId>com.baeldung</groupId>
@@ -0,0 +1,7 @@
+#!/usr/bin/env bash
+java --module-path mods:libs \
+--add-modules com.baeldung.library.core \
+--add-opens com.baeldung.library.core/com.baeldung.library.core=org.junit.platform.commons \
+--add-reads com.baeldung.library.core=org.junit.jupiter.api \
+--patch-module com.baeldung.library.core=outDir/library-test \
+--module org.junit.platform.console --select-class com.baeldung.library.core.LibraryUnitTest
@@ -0,0 +1,2 @@
+#!/usr/bin/env bash
+java --module-path mods --module com.baeldung.library.core/com.baeldung.library.core.Main
@@ -0,0 +1,5 @@
+#!/usr/bin/env bash
+java --module-path libs \
+org.junit.platform.console.ConsoleLauncher \
+--classpath ./outDir/library-core \
+--select-class com.baeldung.library.core.LibraryUnitTest
--- a/Show More
+++ b/Show More