diff --git a/core-java-modules/core-java-8-2/.gitignore b/core-java-modules/core-java-8-2/.gitignore new file mode 100644 index 0000000000..374c8bf907 --- /dev/null +++ b/core-java-modules/core-java-8-2/.gitignore @@ -0,0 +1,25 @@ +*.class + +0.* + +#folders# +/target +/neoDb* +/data +/src/main/webapp/WEB-INF/classes +*/META-INF/* +.resourceCache + +# Packaged files # +*.jar +*.war +*.ear + +# Files generated by integration tests +backup-pom.xml +/bin/ +/temp + +#IntelliJ specific +.idea/ +*.iml \ No newline at end of file diff --git a/core-java-modules/core-java-8-2/README.md b/core-java-modules/core-java-8-2/README.md new file mode 100644 index 0000000000..9b6a0f1716 --- /dev/null +++ b/core-java-modules/core-java-8-2/README.md @@ -0,0 +1,13 @@ +## Java 8 核心（第 2 部分） + +本模块中包含有关 Java 8 核心新增功能特性的一些文章。 + +### 相关文章 + +- [Run a Java Application from the Command Line](https://www.baeldung.com/java-run-jar-with-arguments) +- [Java 8 Stream skip() vs limit()](https://www.baeldung.com/java-stream-skip-vs-limit) +- [Guide to Java BiFunction Interface](https://www.baeldung.com/java-bifunction-interface) +- [Interface With Default Methods vs Abstract Class](https://www.baeldung.com/java-interface-default-method-vs-abstract-class) +- [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) +- [[<-- Java 8 核心（第 1 部分）]](/core-java-modules/core-java-8) diff --git a/core-java-modules/core-java-8-2/pom.xml b/core-java-modules/core-java-8-2/pom.xml new file mode 100644 index 0000000000..6b3338804e --- /dev/null +++ b/core-java-modules/core-java-8-2/pom.xml @@ -0,0 +1,29 @@ + + + 4.0.0 + core-java-8-2 + 0.1.0-SNAPSHOT + core-java-8-2 + jar + + + com.ossez.core-java-modules + core-java-modules + 0.0.2-SNAPSHOT + + + + + com.ibm.icu + icu4j + ${icu.version} + + + + + 64.2 + + + \ No newline at end of file diff --git a/core-java-modules/core-java-8-2/src/main/java/com/ossez/game/RockPaperScissorsGame.java b/core-java-modules/core-java-8-2/src/main/java/com/ossez/game/RockPaperScissorsGame.java new file mode 100644 index 0000000000..688497e6e4 --- /dev/null +++ b/core-java-modules/core-java-8-2/src/main/java/com/ossez/game/RockPaperScissorsGame.java @@ -0,0 +1,73 @@ +package com.ossez.game; + +import java.util.*; + +class RockPaperScissorsGame { + + enum Move { + ROCK("rock"), + PAPER("paper"), + SCISSORS("scissors"); + + private String value; + + Move(String value) { + this.value = value; + } + + public String getValue() { + return value; + } + } + + public static void main(String[] args) { + Scanner scanner = new Scanner(System.in); + int wins = 0; + int losses = 0; + + System.out.println("Welcome to Rock-Paper-Scissors! Please enter \"rock\", \"paper\", \"scissors\", or \"quit\" to exit."); + + while (true) { + System.out.println("-------------------------"); + System.out.print("Enter your move: "); + String playerMove = scanner.nextLine(); + + if (playerMove.equals("quit")) { + System.out.println("You won " + wins + " times and lost " + losses + " times."); + System.out.println("Thanks for playing! See you again."); + break; + } + + if (Arrays.stream(Move.values()).noneMatch(x -> x.getValue().equals(playerMove))) { + System.out.println("Your move isn't valid!"); + continue; + } + + String computerMove = getComputerMove(); + + if (playerMove.equals(computerMove)) { + System.out.println("It's a tie!"); + } else if (isPlayerWin(playerMove, computerMove)) { + System.out.println("You won!"); + wins++; + } else { + System.out.println("You lost!"); + losses++; + } + } + } + + private static boolean isPlayerWin(String playerMove, String computerMove) { + return playerMove.equals(Move.ROCK.value) && computerMove.equals(Move.SCISSORS.value) + || (playerMove.equals(Move.SCISSORS.value) && computerMove.equals(Move.PAPER.value)) + || (playerMove.equals(Move.PAPER.value) && computerMove.equals(Move.ROCK.value)); + } + + private static String getComputerMove() { + Random random = new Random(); + int randomNumber = random.nextInt(3); + String computerMove = Move.values()[randomNumber].getValue(); + System.out.println("Computer move: " + computerMove); + return computerMove; + } +} \ No newline at end of file diff --git a/core-java-modules/core-java-8-2/src/main/java/com/ossez/interfaceVsAbstractClass/ChidlCircleInterfaceImpl.java b/core-java-modules/core-java-8-2/src/main/java/com/ossez/interfaceVsAbstractClass/ChidlCircleInterfaceImpl.java new file mode 100644 index 0000000000..c403c7e800 --- /dev/null +++ b/core-java-modules/core-java-8-2/src/main/java/com/ossez/interfaceVsAbstractClass/ChidlCircleInterfaceImpl.java @@ -0,0 +1,14 @@ +package com.ossez.interfaceVsAbstractClass; + +public class ChidlCircleInterfaceImpl implements CircleInterface { + private String color; + + @Override + public String getColor() { + return color; + } + + public void setColor(String color) { + this.color = color; + } +} diff --git a/core-java-modules/core-java-8-2/src/main/java/com/ossez/interfaceVsAbstractClass/ChildCircleClass.java b/core-java-modules/core-java-8-2/src/main/java/com/ossez/interfaceVsAbstractClass/ChildCircleClass.java new file mode 100644 index 0000000000..5de63ecd03 --- /dev/null +++ b/core-java-modules/core-java-8-2/src/main/java/com/ossez/interfaceVsAbstractClass/ChildCircleClass.java @@ -0,0 +1,5 @@ +package com.ossez.interfaceVsAbstractClass; + +public class ChildCircleClass extends CircleClass { + +} diff --git a/core-java-modules/core-java-8-2/src/main/java/com/ossez/interfaceVsAbstractClass/CircleClass.java b/core-java-modules/core-java-8-2/src/main/java/com/ossez/interfaceVsAbstractClass/CircleClass.java new file mode 100644 index 0000000000..da7a3c4ad2 --- /dev/null +++ b/core-java-modules/core-java-8-2/src/main/java/com/ossez/interfaceVsAbstractClass/CircleClass.java @@ -0,0 +1,23 @@ +package com.ossez.interfaceVsAbstractClass; + +import java.util.Arrays; +import java.util.List; + +public abstract class CircleClass { + + private String color; + private List allowedColors = Arrays.asList("RED", "GREEN", "BLUE"); + + public boolean isValid() { + return allowedColors.contains(getColor()); + } + + public String getColor() { + return color; + } + + public void setColor(String color) { + this.color = color; + } + +} diff --git a/core-java-modules/core-java-8-2/src/main/java/com/ossez/interfaceVsAbstractClass/CircleInterface.java b/core-java-modules/core-java-8-2/src/main/java/com/ossez/interfaceVsAbstractClass/CircleInterface.java new file mode 100644 index 0000000000..ed3e69d632 --- /dev/null +++ b/core-java-modules/core-java-8-2/src/main/java/com/ossez/interfaceVsAbstractClass/CircleInterface.java @@ -0,0 +1,14 @@ +package com.ossez.interfaceVsAbstractClass; + +import java.util.Arrays; +import java.util.List; + +public interface CircleInterface { + List allowedColors = Arrays.asList("RED", "GREEN", "BLUE"); + + String getColor(); + + public default boolean isValid() { + return allowedColors.contains(getColor()); + } +} diff --git a/core-java-modules/core-java-8-2/src/main/java/com/ossez/jarArguments/JarExample.java b/core-java-modules/core-java-8-2/src/main/java/com/ossez/jarArguments/JarExample.java new file mode 100644 index 0000000000..0a173a9879 --- /dev/null +++ b/core-java-modules/core-java-8-2/src/main/java/com/ossez/jarArguments/JarExample.java @@ -0,0 +1,18 @@ +package com.ossez.jarArguments; + +public class JarExample { + + public static void main(String[] args) { + System.out.println("Hello Baeldung Reader in JarExample!"); + + if(args == null) { + System.out.println("You have not provided any arguments!"); + }else { + System.out.println("There are "+args.length+" argument(s)!"); + for(int i=0; i locales = Arrays.asList(new Locale[] { Locale.UK, Locale.ITALY, Locale.FRANCE, Locale.forLanguageTag("pl-PL") }); + Localization.run(locales); + JavaSEFormat.run(locales); + ICUFormat.run(locales); + } + +} diff --git a/core-java-modules/core-java-8-2/src/main/java/com/ossez/localization/ICUFormat.java b/core-java-modules/core-java-8-2/src/main/java/com/ossez/localization/ICUFormat.java new file mode 100644 index 0000000000..7e91653830 --- /dev/null +++ b/core-java-modules/core-java-8-2/src/main/java/com/ossez/localization/ICUFormat.java @@ -0,0 +1,29 @@ +package com.ossez.localization; + +import java.util.List; +import java.util.Locale; +import java.util.ResourceBundle; + +import com.ibm.icu.text.MessageFormat; + +public class ICUFormat { + + public static String getLabel(Locale locale, Object[] data) { + ResourceBundle bundle = ResourceBundle.getBundle("formats", locale); + String format = bundle.getString("label-icu"); + MessageFormat formatter = new MessageFormat(format, locale); + return formatter.format(data); + } + + public static void run(List locales) { + System.out.println("ICU formatter"); + locales.forEach(locale -> System.out.println(getLabel(locale, new Object[] { "Alice", "female", 0 }))); + locales.forEach(locale -> System.out.println(getLabel(locale, new Object[] { "Alice", "female", 1 }))); + locales.forEach(locale -> System.out.println(getLabel(locale, new Object[] { "Alice", "female", 2 }))); + locales.forEach(locale -> System.out.println(getLabel(locale, new Object[] { "Alice", "female", 3 }))); + locales.forEach(locale -> System.out.println(getLabel(locale, new Object[] { "Bob", "male", 0 }))); + locales.forEach(locale -> System.out.println(getLabel(locale, new Object[] { "Bob", "male", 1 }))); + locales.forEach(locale -> System.out.println(getLabel(locale, new Object[] { "Bob", "male", 2 }))); + locales.forEach(locale -> System.out.println(getLabel(locale, new Object[] { "Bob", "male", 3 }))); + } +} diff --git a/core-java-modules/core-java-8-2/src/main/java/com/ossez/localization/JavaSEFormat.java b/core-java-modules/core-java-8-2/src/main/java/com/ossez/localization/JavaSEFormat.java new file mode 100644 index 0000000000..cfffa70323 --- /dev/null +++ b/core-java-modules/core-java-8-2/src/main/java/com/ossez/localization/JavaSEFormat.java @@ -0,0 +1,24 @@ +package com.ossez.localization; + +import java.text.MessageFormat; +import java.util.Date; +import java.util.List; +import java.util.Locale; +import java.util.ResourceBundle; + +public class JavaSEFormat { + + public static String getLabel(Locale locale, Object[] data) { + ResourceBundle bundle = ResourceBundle.getBundle("formats", locale); + final String pattern = bundle.getString("label"); + final MessageFormat formatter = new MessageFormat(pattern, locale); + return formatter.format(data); + } + + public static void run(List locales) { + System.out.println("Java formatter"); + final Date date = new Date(System.currentTimeMillis()); + locales.forEach(locale -> System.out.println(getLabel(locale, new Object[] { date, "Alice", 0 }))); + locales.forEach(locale -> System.out.println(getLabel(locale, new Object[] { date, "Alice", 2 }))); + } +} diff --git a/core-java-modules/core-java-8-2/src/main/java/com/ossez/localization/Localization.java b/core-java-modules/core-java-8-2/src/main/java/com/ossez/localization/Localization.java new file mode 100644 index 0000000000..945baf4ee9 --- /dev/null +++ b/core-java-modules/core-java-8-2/src/main/java/com/ossez/localization/Localization.java @@ -0,0 +1,18 @@ +package com.ossez.localization; + +import java.util.List; +import java.util.Locale; +import java.util.ResourceBundle; + +public class Localization { + + public static String getLabel(Locale locale) { + final ResourceBundle bundle = ResourceBundle.getBundle("messages", locale); + return bundle.getString("label"); + } + + public static void run(List locales) { + locales.forEach(locale -> System.out.println(getLabel(locale))); + } + +} diff --git a/core-java-modules/core-java-8-2/src/main/java/com/ossez/stream/SkipLimitComparison.java b/core-java-modules/core-java-8-2/src/main/java/com/ossez/stream/SkipLimitComparison.java new file mode 100644 index 0000000000..8ed279a060 --- /dev/null +++ b/core-java-modules/core-java-8-2/src/main/java/com/ossez/stream/SkipLimitComparison.java @@ -0,0 +1,46 @@ +package com.ossez.stream; + +import java.util.List; +import java.util.stream.Collectors; +import java.util.stream.Stream; + +public class SkipLimitComparison { + + public static void main(String[] args) { + skipExample(); + limitExample(); + limitInfiniteStreamExample(); + getEvenNumbers(10, 10).stream() + .forEach(System.out::println); + } + + public static void skipExample() { + Stream.of(1, 2, 3, 4, 5, 6, 7, 8, 9, 10) + .filter(i -> i % 2 == 0) + .skip(2) + .forEach(i -> System.out.print(i + " ")); + } + + public static void limitExample() { + Stream.of(1, 2, 3, 4, 5, 6, 7, 8, 9, 10) + .filter(i -> i % 2 == 0) + .limit(2) + .forEach(i -> System.out.print(i + " ")); + } + + public static void limitInfiniteStreamExample() { + Stream.iterate(0, i -> i + 1) + .filter(i -> i % 2 == 0) + .limit(10) + .forEach(System.out::println); + } + + private static List getEvenNumbers(int offset, int limit) { + return Stream.iterate(0, i -> i + 1) + .filter(i -> i % 2 == 0) + .skip(offset) + .limit(limit) + .collect(Collectors.toList()); + } + +} diff --git a/core-java-modules/core-java-8-2/src/main/java/com/ossez/uuid/UuidHelper.java b/core-java-modules/core-java-8-2/src/main/java/com/ossez/uuid/UuidHelper.java new file mode 100644 index 0000000000..bfc75d961e --- /dev/null +++ b/core-java-modules/core-java-8-2/src/main/java/com/ossez/uuid/UuidHelper.java @@ -0,0 +1,33 @@ +package com.ossez.uuid; + +import java.nio.ByteBuffer; +import java.util.Arrays; +import java.util.UUID; + +public class UuidHelper { + + public static byte[] convertUUIDToBytes(UUID uuid) { + ByteBuffer bb = ByteBuffer.wrap(new byte[16]); + bb.putLong(uuid.getMostSignificantBits()); + bb.putLong(uuid.getLeastSignificantBits()); + return bb.array(); + } + + public static UUID convertBytesToUUID(byte[] bytes) { + ByteBuffer byteBuffer = ByteBuffer.wrap(bytes); + long high = byteBuffer.getLong(); + long low = byteBuffer.getLong(); + return new UUID(high, low); + } + + public static void main(String[] args) { + UUID uuid = UUID.randomUUID(); + System.out.println("Original UUID: " + uuid); + + byte[] bytes = convertUUIDToBytes(uuid); + System.out.println("Converted byte array: " + Arrays.toString(bytes)); + + UUID uuidNew = convertBytesToUUID(bytes); + System.out.println("Converted UUID: " + uuidNew); + } +} diff --git a/core-java-modules/core-java-8-2/src/main/resources/META-INF/persistence.xml b/core-java-modules/core-java-8-2/src/main/resources/META-INF/persistence.xml new file mode 100644 index 0000000000..c412ca0839 --- /dev/null +++ b/core-java-modules/core-java-8-2/src/main/resources/META-INF/persistence.xml @@ -0,0 +1,34 @@ + + + + + Persist Optional Return Type Demo + org.hibernate.jpa.HibernatePersistenceProvider + com.baeldung.optionalreturntype.User + com.baeldung.optionalreturntype.UserOptional + + true + + + + + + + + + + + + + \ No newline at end of file diff --git a/core-java-modules/core-java-8-2/src/main/resources/example_manifest.txt b/core-java-modules/core-java-8-2/src/main/resources/example_manifest.txt new file mode 100644 index 0000000000..71abcb05fb --- /dev/null +++ b/core-java-modules/core-java-8-2/src/main/resources/example_manifest.txt @@ -0,0 +1 @@ +Main-Class: com.baeldung.jarArguments.JarExample diff --git a/core-java-modules/core-java-8-2/src/main/resources/formats_en.properties b/core-java-modules/core-java-8-2/src/main/resources/formats_en.properties new file mode 100644 index 0000000000..41e0e00119 --- /dev/null +++ b/core-java-modules/core-java-8-2/src/main/resources/formats_en.properties @@ -0,0 +1,2 @@ +label=On {0, date, short} {1} has sent you {2, choice, 0#no messages|1#a message|2#two messages|2<{2,number,integer} messages}. +label-icu={0} has sent you {2, plural, =0 {no messages} =1 {a message} other {{2, number, integer} messages}}. \ No newline at end of file diff --git a/core-java-modules/core-java-8-2/src/main/resources/formats_fr.properties b/core-java-modules/core-java-8-2/src/main/resources/formats_fr.properties new file mode 100644 index 0000000000..c2d5159b32 --- /dev/null +++ b/core-java-modules/core-java-8-2/src/main/resources/formats_fr.properties @@ -0,0 +1,2 @@ +label={0, date, short}, {1}{2, choice, 0# ne|0<} vous a envoy {2, choice, 0#aucun message|1#un message|2#deux messages|2<{2,number,integer} messages}. +label-icu={0} {2, plural, =0 {ne } other {}}vous a envoy {2, plural, =0 {aucun message} =1 {un message} other {{2, number, integer} messages}}. \ No newline at end of file diff --git a/core-java-modules/core-java-8-2/src/main/resources/formats_it.properties b/core-java-modules/core-java-8-2/src/main/resources/formats_it.properties new file mode 100644 index 0000000000..43fd1eee1c --- /dev/null +++ b/core-java-modules/core-java-8-2/src/main/resources/formats_it.properties @@ -0,0 +1,2 @@ +label={0, date, short} {1} ti ha inviato {2, choice, 0#nessun messagio|1#un messaggio|2#due messaggi|2<{2, number, integer} messaggi}. +label-icu={0} {2, plural, =0 {non } other {}}ti ha inviato {2, plural, =0 {nessun messaggio} =1 {un messaggio} other {{2, number, integer} messaggi}}. \ No newline at end of file diff --git a/core-java-modules/core-java-8-2/src/main/resources/formats_pl.properties b/core-java-modules/core-java-8-2/src/main/resources/formats_pl.properties new file mode 100644 index 0000000000..9333ec3396 --- /dev/null +++ b/core-java-modules/core-java-8-2/src/main/resources/formats_pl.properties @@ -0,0 +1,2 @@ +label=W {0, date, short} {1}{2, choice, 0# nie|0<} wys\u0142a\u0142a ci {2, choice, 0#\u017Cadnych wiadomo\u015Bci|1#wiadomo\u015B\u0107|2#dwie wiadomo\u015Bci|2<{2, number, integer} wiadomo\u015Bci}. +label-icu={0} {2, plural, =0 {nie } other {}}{1, select, male {wys\u0142a\u0142} female {wys\u0142a\u0142a} other {wys\u0142a\u0142o}} ci {2, plural, =0 {\u017Cadnej wiadomo\u015Bci} =1 {wiadomo\u015B\u0107} other {{2, number, integer} wiadomo\u015Bci}}. diff --git a/core-java-modules/core-java-8-2/src/main/resources/messages_en.properties b/core-java-modules/core-java-8-2/src/main/resources/messages_en.properties new file mode 100644 index 0000000000..bcbca9483c --- /dev/null +++ b/core-java-modules/core-java-8-2/src/main/resources/messages_en.properties @@ -0,0 +1 @@ +label=Alice has sent you a message. diff --git a/core-java-modules/core-java-8-2/src/main/resources/messages_fr.properties b/core-java-modules/core-java-8-2/src/main/resources/messages_fr.properties new file mode 100644 index 0000000000..6716102568 --- /dev/null +++ b/core-java-modules/core-java-8-2/src/main/resources/messages_fr.properties @@ -0,0 +1 @@ +label=Alice vous a envoy un message. \ No newline at end of file diff --git a/core-java-modules/core-java-8-2/src/main/resources/messages_it.properties b/core-java-modules/core-java-8-2/src/main/resources/messages_it.properties new file mode 100644 index 0000000000..6929a8c091 --- /dev/null +++ b/core-java-modules/core-java-8-2/src/main/resources/messages_it.properties @@ -0,0 +1 @@ +label=Alice ti ha inviato un messaggio. \ No newline at end of file diff --git a/core-java-modules/core-java-8-2/src/main/resources/messages_pl.properties b/core-java-modules/core-java-8-2/src/main/resources/messages_pl.properties new file mode 100644 index 0000000000..5515a9920e --- /dev/null +++ b/core-java-modules/core-java-8-2/src/main/resources/messages_pl.properties @@ -0,0 +1 @@ +label=Alice wys\u0142a\u0142a ci wiadomo\u015B\u0107. \ No newline at end of file diff --git a/core-java-modules/core-java-8-2/src/test/java/com/ossez/bifunction/BiFunctionalInterfacesUnitTest.java b/core-java-modules/core-java-8-2/src/test/java/com/ossez/bifunction/BiFunctionalInterfacesUnitTest.java new file mode 100644 index 0000000000..c20fcdf5a4 --- /dev/null +++ b/core-java-modules/core-java-8-2/src/test/java/com/ossez/bifunction/BiFunctionalInterfacesUnitTest.java @@ -0,0 +1,164 @@ +package com.ossez.bifunction; + +import org.junit.Test; + +import java.util.ArrayList; +import java.util.Arrays; +import java.util.Comparator; +import java.util.List; +import java.util.function.BiFunction; +import java.util.stream.Collectors; +import java.util.stream.Stream; + +import static org.assertj.core.api.Assertions.assertThat; + +public class BiFunctionalInterfacesUnitTest { + @Test + public void givenStreamValues_whenMappedToNewValues() { + List mapped = Stream.of("hello", "world") + .map(word -> word + "!") + .collect(Collectors.toList()); + + assertThat(mapped).containsExactly("hello!", "world!"); + } + + @Test + public void givenStreamValues_whenReducedWithPrefixingOperation() { + String result = Stream.of("hello", "world") + .reduce("", (a, b) -> b + "-" + a); + + assertThat(result).isEqualTo("world-hello-"); + } + + @Test + public void givenStreamValues_whenReducedWithPrefixingLambda_thenHasNoTrailingDash() { + String result = Stream.of("hello", "world") + .reduce("", (a, b) -> combineWithoutTrailingDash(a, b)); + + assertThat(result).isEqualTo("world-hello"); + } + + private String combineWithoutTrailingDash(String a, String b) { + if (a.isEmpty()) { + return b; + } + return b + "-" + a; + } + + @Test + public void givenStreamValues_whenReducedWithPrefixingMethodReference_thenHasNoTrailingDash() { + String result = Stream.of("hello", "world") + .reduce("", this::combineWithoutTrailingDash); + + assertThat(result).isEqualTo("world-hello"); + } + + @Test + public void givenTwoLists_whenCombined() { + List list1 = Arrays.asList("a", "b", "c"); + List list2 = Arrays.asList(1, 2, 3); + + List result = new ArrayList<>(); + for (int i=0; i < list1.size(); i++) { + result.add(list1.get(i) + list2.get(i)); + } + + assertThat(result).containsExactly("a1", "b2", "c3"); + } + + @Test + public void givenTwoLists_whenCombinedWithGeneralPurposeCombiner() { + List list1 = Arrays.asList("a", "b", "c"); + List list2 = Arrays.asList(1, 2, 3); + + List result = listCombiner(list1, list2, (a, b) -> a + b); + + assertThat(result).containsExactly("a1", "b2", "c3"); + } + + private static List listCombiner(List list1, + List list2, + BiFunction combiner) { + List result = new ArrayList<>(); + for (int i = 0; i < list1.size(); i++) { + result.add(combiner.apply(list1.get(i), list2.get(i))); + } + return result; + } + + @Test + public void givenTwoLists_whenComparedWithCombiningFunction() { + List list1 = Arrays.asList(1.0d, 2.1d, 3.3d); + List list2 = Arrays.asList(0.1f, 0.2f, 4f); + + // algorithm to determine if the value in list1 > value in list 2 + List result = listCombiner(list1, list2, (a, b) -> a > b); + + assertThat(result).containsExactly(true, true, false); + } + + @Test + public void givenTwoLists_whenComparedWithCombiningFunctionByMethodReference() { + List list1 = Arrays.asList(1.0d, 2.1d, 3.3d); + List list2 = Arrays.asList(0.1f, 0.2f, 4f); + + // algorithm to determine if the value in list1 > value in list 2 + List result = listCombiner(list1, list2, this::firstIsGreaterThanSecond); + + assertThat(result).containsExactly(true, true, false); + } + + private boolean firstIsGreaterThanSecond(Double a, Float b) { + return a > b; + } + + @Test + public void givenTwoLists_whenComparedForEqualityByCombiningFunction() { + List list1 = Arrays.asList(0.1f, 0.2f, 4f); + List list2 = Arrays.asList(0.1f, 0.2f, 4f); + + List result = listCombiner(list1, list2, (a, b) -> a.equals(b)); + + assertThat(result).containsExactly(true, true, true); + } + + @Test + public void givenTwoLists_whenComparedForEqualityByCombiningFunctionWithMethodReference() { + List list1 = Arrays.asList(0.1f, 0.2f, 4f); + List list2 = Arrays.asList(0.1f, 0.2f, 4f); + + List result = listCombiner(list1, list2, Float::equals); + + assertThat(result).containsExactly(true, true, true); + } + + @Test + public void givenTwoLists_whenComparedWithCombiningFunctionWithCompareTo() { + List list1 = Arrays.asList(1.0d, 2.1d, 3.3d); + List list2 = Arrays.asList(0.1d, 0.2d, 4d); + + List result = listCombiner(list1, list2, Double::compareTo); + + assertThat(result).containsExactly(1, 1, -1); + } + + /** + * Allows you to to pass in a lambda or method reference and then + * get access to the BiFunction it is meant to become + */ + private static BiFunction asBiFunction(BiFunction function) { + return function; + } + + @Test + public void givenTwoLists_whenComparedWithCombiningFunctionWithComposedBiFunction() { + List list1 = Arrays.asList(1.0d, 2.1d, 3.3d); + List list2 = Arrays.asList(0.1d, 0.2d, 4d); + + List result = listCombiner(list1, list2, + asBiFunction(Double::compareTo) + .andThen(i -> i > 0)); + + assertThat(result).containsExactly(true, true, false); + } +} diff --git a/core-java-modules/core-java-8-2/src/test/java/com/ossez/interfaceVsAbstractClass/InterfaceVsAbstractClassUnitTest.java b/core-java-modules/core-java-8-2/src/test/java/com/ossez/interfaceVsAbstractClass/InterfaceVsAbstractClassUnitTest.java new file mode 100644 index 0000000000..8c4729a895 --- /dev/null +++ b/core-java-modules/core-java-8-2/src/test/java/com/ossez/interfaceVsAbstractClass/InterfaceVsAbstractClassUnitTest.java @@ -0,0 +1,21 @@ +package com.ossez.interfaceVsAbstractClass; + +import static org.junit.Assert.assertTrue; + +import org.junit.Test; + +public class InterfaceVsAbstractClassUnitTest { + @Test + public void givenAbstractClass_whenValidCircleUsed_thenPass() { + CircleClass redCircle = new ChildCircleClass(); + redCircle.setColor("RED"); + assertTrue(redCircle.isValid()); + } + + @Test + public void givenInterface_whenValidCircleWithoutStateUsed_thenPass() { + ChidlCircleInterfaceImpl redCircleWithoutState = new ChidlCircleInterfaceImpl(); + redCircleWithoutState.setColor("RED"); + assertTrue(redCircleWithoutState.isValid()); + } +} diff --git a/core-java-modules/core-java-8-2/src/test/java/com/ossez/localization/ICUFormatUnitTest.java b/core-java-modules/core-java-8-2/src/test/java/com/ossez/localization/ICUFormatUnitTest.java new file mode 100644 index 0000000000..3aef525e91 --- /dev/null +++ b/core-java-modules/core-java-8-2/src/test/java/com/ossez/localization/ICUFormatUnitTest.java @@ -0,0 +1,72 @@ +package com.ossez.localization; + +import static org.junit.Assert.assertEquals; + +import java.util.Locale; + +import org.junit.Test; + +public class ICUFormatUnitTest { + + @Test + public void givenInUK_whenAliceSendsNothing_thenCorrectMessage() { + assertEquals("Alice has sent you no messages.", ICUFormat.getLabel(Locale.UK, new Object[] { "Alice", "female", 0 })); + } + + @Test + public void givenInUK_whenAliceSendsOneMessage_thenCorrectMessage() { + assertEquals("Alice has sent you a message.", ICUFormat.getLabel(Locale.UK, new Object[] { "Alice", "female", 1 })); + } + + @Test + public void givenInUK_whenBobSendsSixMessages_thenCorrectMessage() { + assertEquals("Bob has sent you 6 messages.", ICUFormat.getLabel(Locale.UK, new Object[] { "Bob", "male", 6 })); + } + + @Test + public void givenInItaly_whenAliceSendsNothing_thenCorrectMessage() { + assertEquals("Alice non ti ha inviato nessun messaggio.", ICUFormat.getLabel(Locale.ITALY, new Object[] { "Alice", "female", 0 })); + } + + @Test + public void givenInItaly_whenAliceSendsOneMessage_thenCorrectMessage() { + assertEquals("Alice ti ha inviato un messaggio.", ICUFormat.getLabel(Locale.ITALY, new Object[] { "Alice", "female", 1 })); + } + + @Test + public void givenInItaly_whenBobSendsSixMessages_thenCorrectMessage() { + assertEquals("Bob ti ha inviato 6 messaggi.", ICUFormat.getLabel(Locale.ITALY, new Object[] { "Bob", "male", 6 })); + } + + @Test + public void givenInFrance_whenAliceSendsNothing_thenCorrectMessage() { + assertEquals("Alice ne vous a envoyé aucun message.", ICUFormat.getLabel(Locale.FRANCE, new Object[] { "Alice", "female", 0 })); + } + + @Test + public void givenInFrance_whenAliceSendsOneMessage_thenCorrectMessage() { + assertEquals("Alice vous a envoyé un message.", ICUFormat.getLabel(Locale.FRANCE, new Object[] { "Alice", "female", 1 })); + } + + @Test + public void givenInFrance_whenBobSendsSixMessages_thenCorrectMessage() { + assertEquals("Bob vous a envoyé 6 messages.", ICUFormat.getLabel(Locale.FRANCE, new Object[] { "Bob", "male", 6 })); + } + + + @Test + public void givenInPoland_whenAliceSendsNothing_thenCorrectMessage() { + assertEquals("Alice nie wysłała ci żadnej wiadomości.", ICUFormat.getLabel(Locale.forLanguageTag("pl-PL"), new Object[] { "Alice", "female", 0 })); + } + + @Test + public void givenInPoland_whenAliceSendsOneMessage_thenCorrectMessage() { + assertEquals("Alice wysłała ci wiadomość.", ICUFormat.getLabel(Locale.forLanguageTag("pl-PL"), new Object[] { "Alice", "female", 1 })); + } + + @Test + public void givenInPoland_whenBobSendsSixMessages_thenCorrectMessage() { + assertEquals("Bob wysłał ci 6 wiadomości.", ICUFormat.getLabel(Locale.forLanguageTag("pl-PL"), new Object[] { "Bob", "male", 6 })); + } + +} diff --git a/core-java-modules/core-java-8/README.md b/core-java-modules/core-java-8/README.md index d7a9ff7cbc..e207871def 100644 --- a/core-java-modules/core-java-8/README.md +++ b/core-java-modules/core-java-8/README.md @@ -1,6 +1,6 @@ ## Java 8 核心 -本模块中包含有关 Java 8 核心新增功能特性的一些文章 +本模块中包含有关 Java 8 核心新增功能特性的一些文章。 ### 相关文章: - [New Features in Java 8](https://www.baeldung.com/java-8-new-features) @@ -12,4 +12,4 @@ - [Finding Min/Max in an Array with Java](https://www.baeldung.com/java-array-min-max) - [Internationalization and Localization in Java 8](https://www.baeldung.com/java-8-localization) - [Generalized Target-Type Inference in Java](https://www.baeldung.com/java-generalized-target-type-inference) -- [[More -->]](/core-java-modules/core-java-8-2) +- [[Java 8 核心（第 2 部分） -->]](/core-java-modules/core-java-8-2)