Simply Gradle plugin DSL for configuring a jar or war's launch script

Closes gh-9948

spring-boot-tools/spring-boot-gradle-plugin/src/main/gradle/packaging/boot-jar-custom-launch-script.gradle

@@ -14,7 +14,6 @@ bootJar {
 // tag::custom-launch-script[]
 bootJar {
 	launchScript {
-		included = true
 		script = file('src/custom.script')
 	}
 }

spring-boot-tools/spring-boot-gradle-plugin/src/main/gradle/packaging/boot-jar-include-launch-script.gradle

@@ -13,8 +13,6 @@ bootJar {
 
 // tag::include-launch-script[]
 bootJar {
-	launchScript {
-		included = true
-	}
+	launchScript()
 }
 // end::include-launch-script[]

spring-boot-tools/spring-boot-gradle-plugin/src/main/gradle/packaging/boot-jar-launch-script-properties.gradle

@@ -14,7 +14,6 @@ bootJar {
 // tag::launch-script-properties[]
 bootJar {
 	launchScript {
-		included = true
 		properties 'logFilename': 'example-app.log'
 	}
 }

spring-boot-tools/spring-boot-gradle-plugin/src/main/java/org/springframework/boot/gradle/tasks/bundling/BootArchive.java

@@ -67,17 +67,24 @@ public interface BootArchive extends Task {
 	void requiresUnpack(Spec<FileTreeElement> spec);
 
 	/**
-	 * Returns the {@link LaunchScriptConfiguration} that will control the script, if any,
-	 * that is prepended to the archive.
+	 * Returns the {@link LaunchScriptConfiguration} that will control the script that is
+	 * prepended to the archive.
 	 *
-	 * @return the launch script configuration
+	 * @return the launch script configuration, or {@code null} if the launch script has
+	 * not been configured.
 	 */
 	@Input
+	@Optional
 	LaunchScriptConfiguration getLaunchScript();
 
 	/**
-	 * Applies the given {@code action} to the {@link LaunchScriptConfiguration} of this
-	 * archive.
+	 * Configures the archive to have a prepended launch script.
+	 */
+	void launchScript();
+
+	/**
+	 * Configures the archive to have a prepended launch script, customizing its
+	 * configuration using the given {@code action}.
 	 *
 	 * @param action the action to apply
 	 */

spring-boot-tools/spring-boot-gradle-plugin/src/main/java/org/springframework/boot/gradle/tasks/bundling/BootArchiveSupport.java

@@ -61,7 +61,7 @@ class BootArchiveSupport {
 
 	private final String loaderMainClass;
 
-	private LaunchScriptConfiguration launchScript = new LaunchScriptConfiguration();
+	private LaunchScriptConfiguration launchScript;
 
 	private boolean excludeDevtools = true;
 

spring-boot-tools/spring-boot-gradle-plugin/src/main/java/org/springframework/boot/gradle/tasks/bundling/BootJar.java

@@ -97,9 +97,14 @@ public class BootJar extends Jar implements BootArchive {
 		return this.support.getLaunchScript();
 	}
 
+	@Override
+	public void launchScript() {
+		enableLaunchScriptIfNecessary();
+	}
+
 	@Override
 	public void launchScript(Action<LaunchScriptConfiguration> action) {
-		action.execute(getLaunchScript());
+		action.execute(enableLaunchScriptIfNecessary());
 	}
 
 	@Override
@@ -142,4 +147,13 @@ public class BootJar extends Jar implements BootArchive {
 		return ZipCompression.DEFLATED;
 	}
 
+	private LaunchScriptConfiguration enableLaunchScriptIfNecessary() {
+		LaunchScriptConfiguration launchScript = this.support.getLaunchScript();
+		if (launchScript == null) {
+			launchScript = new LaunchScriptConfiguration();
+			this.support.setLaunchScript(launchScript);
+		}
+		return launchScript;
+	}
+
 }

spring-boot-tools/spring-boot-gradle-plugin/src/main/java/org/springframework/boot/gradle/tasks/bundling/BootWar.java

@@ -91,9 +91,14 @@ public class BootWar extends War implements BootArchive {
 		return this.support.getLaunchScript();
 	}
 
+	@Override
+	public void launchScript() {
+		enableLaunchScriptIfNecessary();
+	}
+
 	@Override
 	public void launchScript(Action<LaunchScriptConfiguration> action) {
-		action.execute(getLaunchScript());
+		action.execute(enableLaunchScriptIfNecessary());
 	}
 
 	/**
@@ -150,4 +155,13 @@ public class BootWar extends War implements BootArchive {
 		return ZipCompression.DEFLATED;
 	}
 
+	private LaunchScriptConfiguration enableLaunchScriptIfNecessary() {
+		LaunchScriptConfiguration launchScript = this.support.getLaunchScript();
+		if (launchScript == null) {
+			launchScript = new LaunchScriptConfiguration();
+			this.support.setLaunchScript(launchScript);
+		}
+		return launchScript;
+	}
+
 }

spring-boot-tools/spring-boot-gradle-plugin/src/main/java/org/springframework/boot/gradle/tasks/bundling/BootZipCopyAction.java

@@ -183,7 +183,7 @@ class BootZipCopyAction implements CopyAction {
 
 	private void writeLaunchScriptIfNecessary(FileOutputStream fileStream) {
 		try {
-			if (this.launchScript.isIncluded()) {
+			if (this.launchScript != null) {
 				fileStream.write(new DefaultLaunchScript(this.launchScript.getScript(),
 						this.launchScript.getProperties()).toByteArray());
 				this.output.setExecutable(true);

spring-boot-tools/spring-boot-gradle-plugin/src/main/java/org/springframework/boot/gradle/tasks/bundling/LaunchScriptConfiguration.java

@@ -32,30 +32,10 @@ import org.springframework.boot.loader.tools.FileUtils;
  */
 public class LaunchScriptConfiguration implements Serializable {
 
-	private boolean included = false;
-
 	private final Map<String, String> properties = new HashMap<>();
 
 	private File script;
 
-	/**
-	 * Returns whether the launch script is included. Defaults to {@code false}.
-	 *
-	 * @return {@code true} is the script is included, otherwise {@code false}.
-	 */
-	public boolean isIncluded() {
-		return this.included;
-	}
-
-	/**
-	 * Sets whether the launch script is included. Defaults to {@code false}.
-	 *
-	 * @param included {@code true} is the script is included, otherwise {@code false}.
-	 */
-	public void setIncluded(boolean included) {
-		this.included = included;
-	}
-
 	/**
 	 * Returns the properties that are applied to the launch script when it's being
 	 * including in the executable archive.
@@ -100,7 +80,6 @@ public class LaunchScriptConfiguration implements Serializable {
 	public int hashCode() {
 		final int prime = 31;
 		int result = 1;
-		result = prime * result + (this.included ? 1231 : 1237);
 		result = prime * result
 				+ ((this.properties == null) ? 0 : this.properties.hashCode());
 		result = prime * result + ((this.script == null) ? 0 : this.script.hashCode());
@@ -119,9 +98,6 @@ public class LaunchScriptConfiguration implements Serializable {
 			return false;
 		}
 		LaunchScriptConfiguration other = (LaunchScriptConfiguration) obj;
-		if (this.included != other.included) {
-			return false;
-		}
 		if (!this.properties.equals(other.properties)) {
 			return false;
 		}

spring-boot-tools/spring-boot-gradle-plugin/src/test/java/org/springframework/boot/gradle/tasks/bundling/AbstractBootArchiveTests.java

@@ -184,7 +184,7 @@ public abstract class AbstractBootArchiveTests<T extends Jar & BootArchive> {
 	@Test
 	public void launchScriptCanBePrepended() throws IOException {
 		this.task.setMainClass("com.example.Main");
-		this.task.getLaunchScript().setIncluded(true);
+		this.task.launchScript();
 		this.task.execute();
 		assertThat(Files.readAllBytes(this.task.getArchivePath().toPath()))
 				.startsWith(new DefaultLaunchScript(null, null).toByteArray());
@@ -201,12 +201,10 @@ public abstract class AbstractBootArchiveTests<T extends Jar & BootArchive> {
 	@Test
 	public void customLaunchScriptCanBePrepended() throws IOException {
 		this.task.setMainClass("com.example.Main");
-		LaunchScriptConfiguration launchScript = this.task.getLaunchScript();
-		launchScript.setIncluded(true);
 		File customScript = this.temp.newFile("custom.script");
 		Files.write(customScript.toPath(), Arrays.asList("custom script"),
 				StandardOpenOption.CREATE);
-		launchScript.setScript(customScript);
+		this.task.launchScript((configuration) -> configuration.setScript(customScript));
 		this.task.execute();
 		assertThat(Files.readAllBytes(this.task.getArchivePath().toPath()))
 				.startsWith("custom script".getBytes());
@@ -215,9 +213,8 @@ public abstract class AbstractBootArchiveTests<T extends Jar & BootArchive> {
 	@Test
 	public void launchScriptPropertiesAreReplaced() throws IOException {
 		this.task.setMainClass("com.example.Main");
-		LaunchScriptConfiguration launchScript = this.task.getLaunchScript();
-		launchScript.setIncluded(true);
-		launchScript.getProperties().put("initInfoProvides", "test property value");
+		this.task.launchScript((configuration) -> configuration.getProperties()
+				.put("initInfoProvides", "test property value"));
 		this.task.execute();
 		assertThat(Files.readAllBytes(this.task.getArchivePath().toPath()))
 				.containsSequence("test property value".getBytes());

spring-boot-tools/spring-boot-gradle-plugin/src/test/resources/org/springframework/boot/gradle/tasks/bundling/BootJarIntegrationTests.gradle

@@ -9,8 +9,9 @@ apply plugin: 'org.springframework.boot'
 
 bootJar {
 	mainClass = 'com.example.Application'
-	launchScript {
-		included = project.hasProperty('includeLaunchScript') ? includeLaunchScript : false
-		properties 'prop' : project.hasProperty('launchScriptProperty') ? launchScriptProperty : 'default'
+	if (project.hasProperty('includeLaunchScript') ? includeLaunchScript : false) {
+		launchScript {
+			properties 'prop' : project.hasProperty('launchScriptProperty') ? launchScriptProperty : 'default'
+		}
 	}
 }

spring-boot-tools/spring-boot-gradle-plugin/src/test/resources/org/springframework/boot/gradle/tasks/bundling/BootWarIntegrationTests.gradle

@@ -9,8 +9,9 @@ apply plugin: 'org.springframework.boot'
 
 bootWar {
 	mainClass = 'com.example.Application'
-	launchScript {
-		included = project.hasProperty('includeLaunchScript') ? includeLaunchScript : false
-		properties 'prop' : project.hasProperty('launchScriptProperty') ? launchScriptProperty : 'default'
+	if (project.hasProperty('includeLaunchScript') ? includeLaunchScript : false) {
+		launchScript {
+			properties 'prop' : project.hasProperty('launchScriptProperty') ? launchScriptProperty : 'default'
+		}
 	}
 }