From 6a6ac00db2a71d329e10afd8f09059884cc3ede8 Mon Sep 17 00:00:00 2001
From: Alex Tighe <599747+atighe@users.noreply.github.com>
Date: Mon, 7 Aug 2023 13:38:05 -0400
Subject: [PATCH] BAEL-6458: Guide to the yield Keyword in Java (#14440)

* BAEL-6229: committing new example for loading multiple yaml configuration files

* BAEL-6229: updating README.md

* BAEL-6229: adding example one code, commented out

* Revert "BAEL-6229: updating README.md"

This reverts commit 51cd2dcf97f797aa6a723888fd246ef0142242a3.

* BAEL-6229: adding comments around commented out code for first example.

* BAEL-6458: creating new module for conditionals and adding examples for yield

* BAEL-6458: creating new module for conditionals and adding examples for yield

* BAEL-6458: rename methods

* BAEL-6458: clean up pom

* BAEL-6458: convert checks to tests

* BAEL-6458: convert checks to tests

* BAEL-6458: convert checks to tests

* BAEL-6458: move examples to just YieldTest and removed YieldExamples class. Also added assigning the value of the switch expression to a variable instead of returning from method. Also added a non-default exhaustive test.

* BAEL-6458: Test clean up based on initial PR feedback.
---
 .../core-java-conditionals/README.md          |  5 ++
 .../core-java-conditionals/pom.xml            | 58 +++++++++++++
 .../com/baeldung/conditionals/YieldTest.java  | 83 +++++++++++++++++++
 3 files changed, 146 insertions(+)
 create mode 100644 core-java-modules/core-java-conditionals/README.md
 create mode 100644 core-java-modules/core-java-conditionals/pom.xml
 create mode 100644 core-java-modules/core-java-conditionals/src/test/java/com/baeldung/conditionals/YieldTest.java

diff --git a/core-java-modules/core-java-conditionals/README.md b/core-java-modules/core-java-conditionals/README.md
new file mode 100644
index 0000000000..ae5694c3ba
--- /dev/null
+++ b/core-java-modules/core-java-conditionals/README.md
@@ -0,0 +1,5 @@
+## Core Java Conditionals
+
+This module contains articles about Java Conditionals.
+
+### Relevant articles:
diff --git a/core-java-modules/core-java-conditionals/pom.xml b/core-java-modules/core-java-conditionals/pom.xml
new file mode 100644
index 0000000000..2a1290c98e
--- /dev/null
+++ b/core-java-modules/core-java-conditionals/pom.xml
@@ -0,0 +1,58 @@
+<?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>core-java-conditionals</artifactId>
+    <version>0.1.0-SNAPSHOT</version>
+    <name>core-java-compiler</name>
+    <packaging>jar</packaging>
+
+    <parent>
+        <groupId>com.baeldung</groupId>
+        <artifactId>parent-modules</artifactId>
+        <version>1.0.0-SNAPSHOT</version>
+    </parent>
+
+    <dependencies>
+        <dependency>
+            <groupId>org.projectlombok</groupId>
+            <artifactId>lombok</artifactId>
+            <version>1.18.24</version>
+            <scope>provided</scope>
+        </dependency>
+    </dependencies>
+
+    <build>
+        <plugins>
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-compiler-plugin</artifactId>
+                <version>${maven-compiler-plugin.version}</version>
+                <configuration>
+                    <compilerArgs>--enable-preview</compilerArgs>
+                    <source>${maven.compiler.source.version}</source>
+                    <target>${maven.compiler.target.version}</target>
+                    <release>14</release>
+                    <compilerArgs>--enable-preview</compilerArgs>
+                </configuration>
+            </plugin>
+                <plugin>
+                    <groupId>org.apache.maven.plugins</groupId>
+                    <artifactId>maven-surefire-plugin</artifactId>
+                    <version>${surefire.plugin.version}</version>
+                    <configuration>
+                        <argLine>--enable-preview</argLine>
+                    </configuration>
+                </plugin>
+        </plugins>
+    </build>
+
+    <properties>
+        <maven.compiler.source.version>14</maven.compiler.source.version>
+        <maven-compiler-plugin.version>3.8.1</maven-compiler-plugin.version>
+        <maven.compiler.target.version>14</maven.compiler.target.version>
+        <surefire.plugin.version>3.0.0-M3</surefire.plugin.version>
+    </properties>
+
+</project>
\ No newline at end of file
diff --git a/core-java-modules/core-java-conditionals/src/test/java/com/baeldung/conditionals/YieldTest.java b/core-java-modules/core-java-conditionals/src/test/java/com/baeldung/conditionals/YieldTest.java
new file mode 100644
index 0000000000..4ea9126cde
--- /dev/null
+++ b/core-java-modules/core-java-conditionals/src/test/java/com/baeldung/conditionals/YieldTest.java
@@ -0,0 +1,83 @@
+package com.baeldung.conditionals;
+
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+
+class YieldTest {
+
+    enum Number {
+        ONE, TWO, THREE, FOUR
+    }
+
+    @Test
+    void whenSwitchingOnNumberOne_thenWillReturnString() {
+        Number number = Number.ONE;
+        String message;
+        switch (number) {
+            case ONE:
+                message = "Got a 1";
+                break;
+            case TWO:
+                message = "Got a 2";
+                break;
+            default:
+                message = "More than 2";
+        }
+
+        assertEquals("Got a 1", message);
+    }
+
+    @Test
+    void whenSwitchingWithArrowOnNumberTwo_thenWillReturnString() {
+        Number number = Number.TWO;
+        String message = switch (number) {
+            case ONE -> {
+                yield "Got a 1";
+            }
+            case TWO -> {
+                yield "Got a 2";
+            }
+            default -> {
+                yield "More than 2";
+            }
+        };
+
+        assertEquals("Got a 2", message);
+    }
+
+    @Test
+    void whenSwitchingWithArrowNoDefaultOnNumberTwo_thenWillReturnString() {
+        Number number = Number.TWO;
+        String message = switch (number) {
+            case ONE -> {
+                yield "Got a 1";
+            }
+            case TWO -> {
+                yield "Got a 2";
+            }
+            case THREE, FOUR -> {
+                yield "More than 2";
+            }
+        };
+
+        assertEquals("Got a 2", message);
+    }
+
+    @Test
+    void whenSwitchingWithColonOnNumberTwo_thenWillReturnString() {
+        Number number = Number.TWO;
+        String message = switch (number) {
+            case ONE:
+                yield "Got a 1";
+            case TWO:
+                yield "Got a 2";
+            default:
+                yield "More than 2";
+        };
+
+        assertEquals("Got a 2", message);
+    }
+
+}