Add includeLocales configuration property

Author: iherasymenko

README.md

@@ -68,6 +68,7 @@ jlinkApplication {
     excludeFiles = ['/**/legal/**', '/**/man/**']
     excludeJmodSection = ['man', 'headers']
     excludeResources = ['/**/com/example/demo/DemoApplication.class']
+    includeLocales = ['en-CA']
 }
 
 ```

src/main/java/com/github/iherasymenko/jlink/JlinkApplicationPlugin.java

@@ -80,6 +80,7 @@ public void apply(Project project) {
                 task.getExcludeFiles().convention(jlinkApplication.getExcludeFiles());
                 task.getExcludeJmodSection().convention(jlinkApplication.getExcludeJmodSection());
                 task.getExcludeResources().convention(jlinkApplication.getExcludeResources());
+                task.getIncludeLocales().convention(jlinkApplication.getIncludeLocales());
             };
 
             TaskProvider<JlinkImageTask> imageTask = tasks.register("image", JlinkImageTask.class, task -> {

src/main/java/com/github/iherasymenko/jlink/JlinkApplicationPluginExtension.java

@@ -52,4 +52,6 @@ public abstract class JlinkApplicationPluginExtension {
 
     public abstract ListProperty<String> getExcludeResources();
 
+    public abstract ListProperty<String> getIncludeLocales();
+
 }

src/main/java/com/github/iherasymenko/jlink/JlinkImageTask.java

@@ -125,6 +125,9 @@ public JlinkImageTask() {
     @Input
     public abstract ListProperty<String> getExcludeResources();
 
+    @Input
+    public abstract ListProperty<String> getIncludeLocales();
+
     @Inject
     protected abstract FileSystemOperations getFileSystemOperations();
 
@@ -194,6 +197,10 @@ public void execute() throws IOException {
         if (!excludeResources.isEmpty()) {
             args.addAll(List.of("--exclude-resources", excludeResources));
         }
+        String includeLocales = String.join(",", getIncludeLocales().get());
+        if (!includeLocales.isEmpty()) {
+            args.addAll(List.of("--include-locales", includeLocales));
+        }
         getFileSystemOperations().delete(spec -> spec.delete(getOutputFolder().get()));
         invokeJlink(args);
     }

src/test/java/com/github/iherasymenko/jlink/test/IncludeLocalesPluginFunctionalTest.java

@@ -0,0 +1,150 @@
+/*
+ * Copyright 2023 Ihor Herasymenko.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.github.iherasymenko.jlink.test;
+
+import com.github.iherasymenko.jlink.test.fixtures.Text;
+import org.assertj.core.api.InstanceOfAssertFactories;
+import org.gradle.testkit.runner.BuildResult;
+import org.junit.jupiter.api.Test;
+
+import java.io.IOException;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+class IncludeLocalesPluginFunctionalTest extends AbstractTestBase {
+
+    @Test
+    void can_include_locales() throws IOException {
+        build.buildFile = """
+                plugins {
+                	id 'java'
+                	id 'com.github.iherasymenko.jlink'
+                }
+                                
+                group = 'com.example'
+                version = '0.0.1-SNAPSHOT'
+
+                java {
+                	toolchain {
+                		languageVersion = JavaLanguageVersion.of(System.getenv().getOrDefault('TESTING_AGAINST_JDK', '21'))
+                		vendor = JvmVendorSpec.AZUL
+                	}
+                }
+              
+                jlinkApplication {
+                	mainClass = 'com.example.demo.DemoApplication'
+                	mainModule = 'demo.main'
+                    includeLocales = ['en-CA']
+                }
+                """;
+        build.settingsFile = """
+                rootProject.name = 'demo'
+                dependencyResolutionManagement {
+                    repositories {
+                        mavenCentral()
+                    }
+                }
+                """;
+        build.mainClass = """
+                package com.example.demo;
+                               
+                import java.util.Locale;
+                
+                public class DemoApplication {
+                    public static void main(String[] args) {
+                        for (Locale locale : Locale.getAvailableLocales()) {
+                            System.out.println(locale);
+                        }
+                    }
+                }
+                """;
+        build.moduleInfo = """
+                module demo.main {
+                    requires jdk.localedata;
+                }
+                """;
+
+        BuildResult buildResult = build.runner("imageRun").build();
+
+        String[] taskOutput = Text.linesBetweenTags(buildResult.getOutput(), "> Task :imageRun", "BUILD SUCCESSFUL");
+        assertThat(taskOutput)
+                .hasSizeLessThan(10)
+                .contains("en", "en_CA", "en_US", "en_US_POSIX");
+    }
+
+    @Test
+    void many_locales_are_available_by_default() throws IOException {
+        build.buildFile = """
+                plugins {
+                	id 'java'
+                	id 'com.github.iherasymenko.jlink'
+                }
+                                
+                group = 'com.example'
+                version = '0.0.1-SNAPSHOT'
+
+                java {
+                	toolchain {
+                		languageVersion = JavaLanguageVersion.of(System.getenv().getOrDefault('TESTING_AGAINST_JDK', '21'))
+                		vendor = JvmVendorSpec.AZUL
+                	}
+                }
+              
+                jlinkApplication {
+                	mainClass = 'com.example.demo.DemoApplication'
+                	mainModule = 'demo.main'
+                }
+                """;
+        build.settingsFile = """
+                rootProject.name = 'demo'
+                dependencyResolutionManagement {
+                    repositories {
+                        mavenCentral()
+                    }
+                }
+                """;
+        build.mainClass = """
+                package com.example.demo;
+                               
+                import java.util.Arrays;
+                import java.util.Locale;
+                import java.util.Comparator;
+                
+                public class DemoApplication {
+                    public static void main(String[] args) {
+                        Locale[] availableLocales = Locale.getAvailableLocales();
+                        Arrays.sort(availableLocales, Comparator.comparing(Locale::toString));
+                        for (Locale locale : availableLocales) {
+                            System.out.println(locale);
+                        }
+                    }
+                }
+                """;
+        build.moduleInfo = """
+                module demo.main {
+                    requires jdk.localedata;
+                }
+                """;
+
+        BuildResult buildResult = build.runner("imageRun").build();
+
+        String[] taskOutput = Text.linesBetweenTags(buildResult.getOutput(), "> Task :imageRun", "BUILD SUCCESSFUL");
+        assertThat(taskOutput)
+                .hasSizeGreaterThan(100)
+                .contains("uk_UA", "en_CA", "fr_CA");
+    }
+
+}