Rework Repacakger timeout code

Pull up common timeout code into Repackager and remove the need for
custom subclasses.

See gh-7263

Author: philwebb

spring-boot-tools/spring-boot-gradle-plugin/src/main/java/org/springframework/boot/gradle/repackage/RepackageTask.java

@@ -21,7 +21,6 @@
 import java.util.HashSet;
 import java.util.Map;
 import java.util.Set;
-import java.util.concurrent.TimeUnit;
 
 import org.gradle.api.Action;
 import org.gradle.api.DefaultTask;
@@ -35,6 +34,7 @@
 import org.springframework.boot.loader.tools.DefaultLaunchScript;
 import org.springframework.boot.loader.tools.LaunchScript;
 import org.springframework.boot.loader.tools.Repackager;
+import org.springframework.boot.loader.tools.Repackager.MainClassTimeoutWarningListener;
 import org.springframework.util.FileCopyUtils;
 
 /**
@@ -46,8 +46,6 @@
  */
 public class RepackageTask extends DefaultTask {
 
-	private static final long FIND_WARNING_TIMEOUT = TimeUnit.SECONDS.toMillis(10);
-
 	private String customConfiguration;
 
 	private Object withJarTask;
@@ -215,7 +213,9 @@ private void repackage(File file) {
 				copy(file, outputFile);
 				file = outputFile;
 			}
-			Repackager repackager = new LoggingRepackager(file);
+			Repackager repackager = new Repackager(file);
+			repackager.addMainClassTimeoutWarningListener(
+					new LoggingMainClassTimeoutWarningListener());
 			setMainClass(repackager);
 			if (this.extension.convertLayout() != null) {
 				repackager.setLayout(this.extension.convertLayout());
@@ -305,26 +305,13 @@ private Map<String, String> getEmbeddedLaunchScriptProperties() {
 	/**
 	 * {@link Repackager} that also logs when searching takes too long.
 	 */
-	private class LoggingRepackager extends Repackager {
-
-		LoggingRepackager(File source) {
-			super(source);
-		}
+	private class LoggingMainClassTimeoutWarningListener
+			implements MainClassTimeoutWarningListener {
 
 		@Override
-		protected String findMainMethod(java.util.jar.JarFile source) throws IOException {
-			long startTime = System.currentTimeMillis();
-			try {
-				return super.findMainMethod(source);
-			}
-			finally {
-				long duration = System.currentTimeMillis() - startTime;
-				if (duration > FIND_WARNING_TIMEOUT) {
-					getLogger().warn("Searching for the main-class is taking "
-							+ "some time, consider using setting "
-							+ "'springBoot.mainClass'");
-				}
-			}
+		public void handleTimeoutWarning(long duration, String mainMethod) {
+			getLogger().warn("Searching for the main-class is taking "
+					+ "some time, consider using setting " + "'springBoot.mainClass'");
 		}
 
 	}

spring-boot-tools/spring-boot-loader-tools/src/main/java/org/springframework/boot/loader/tools/Repackager.java

@@ -24,6 +24,7 @@
 import java.util.HashSet;
 import java.util.List;
 import java.util.Set;
+import java.util.concurrent.TimeUnit;
 import java.util.jar.JarEntry;
 import java.util.jar.JarFile;
 import java.util.jar.Manifest;
@@ -53,6 +54,10 @@ public class Repackager {
 
 	private static final byte[] ZIP_FILE_HEADER = new byte[] { 'P', 'K', 3, 4 };
 
+	private static final long FIND_WARNING_TIMEOUT = TimeUnit.SECONDS.toMillis(10);
+
+	private List<MainClassTimeoutWarningListener> mainClassTimeoutListeners = new ArrayList<MainClassTimeoutWarningListener>();
+
 	private String mainClass;
 
 	private boolean backupSource = true;
@@ -69,6 +74,16 @@ public Repackager(File source) {
 		this.layout = Layouts.forFile(source);
 	}
 
+	/**
+	 * Add a listener that will be triggered to dispaly a warning if searching for the
+	 * main class takes too long.
+	 * @param listener the listener to add
+	 */
+	public void addMainClassTimeoutWarningListener(
+			MainClassTimeoutWarningListener listener) {
+		this.mainClassTimeoutListeners.add(listener);
+	}
+
 	/**
 	 * Sets the main class that should be run. If not specified the value from the
 	 * MANIFEST will be used, or if no manifest entry is found the archive will be
@@ -281,7 +296,7 @@ private Manifest buildManifest(JarFile source) throws IOException {
 			startClass = manifest.getMainAttributes().getValue(MAIN_CLASS_ATTRIBUTE);
 		}
 		if (startClass == null) {
-			startClass = findMainMethod(source);
+			startClass = findMainMethodWithTimeoutWarning(source);
 		}
 		String launcherClassName = this.layout.getLauncherClassName();
 		if (launcherClassName != null) {
@@ -306,6 +321,18 @@ else if (startClass != null) {
 		return manifest;
 	}
 
+	private String findMainMethodWithTimeoutWarning(JarFile source) throws IOException {
+		long startTime = System.currentTimeMillis();
+		String mainMethod = findMainMethod(source);
+		long duration = System.currentTimeMillis() - startTime;
+		if (duration > FIND_WARNING_TIMEOUT) {
+			for (MainClassTimeoutWarningListener listener : this.mainClassTimeoutListeners) {
+				listener.handleTimeoutWarning(duration, mainMethod);
+			}
+		}
+		return mainMethod;
+	}
+
 	protected String findMainMethod(JarFile source) throws IOException {
 		return MainClassFinder.findSingleMainClass(source,
 				this.layout.getClassesLocation());
@@ -324,6 +351,21 @@ private void deleteFile(File file) {
 		}
 	}
 
+	/**
+	 * Callback interface used to present a warning when finding the main class takes too
+	 * long.
+	 */
+	public interface MainClassTimeoutWarningListener {
+
+		/**
+		 * Handle a timeout warning.
+		 * @param duration the amount of time it took to find the main method
+		 * @param mainMethod the main method that was actually found
+		 */
+		void handleTimeoutWarning(long duration, String mainMethod);
+
+	}
+
 	/**
 	 * An {@code EntryTransformer} that renames entries by applying a prefix.
 	 */

spring-boot-tools/spring-boot-maven-plugin/src/main/java/org/springframework/boot/maven/RepackageMojo.java

@@ -22,14 +22,11 @@
 import java.util.List;
 import java.util.Properties;
 import java.util.Set;
-import java.util.concurrent.TimeUnit;
-import java.util.jar.JarFile;
 
 import org.apache.maven.artifact.Artifact;
 import org.apache.maven.model.Dependency;
 import org.apache.maven.plugin.MojoExecutionException;
 import org.apache.maven.plugin.MojoFailureException;
-import org.apache.maven.plugin.logging.Log;
 import org.apache.maven.plugins.annotations.Component;
 import org.apache.maven.plugins.annotations.LifecyclePhase;
 import org.apache.maven.plugins.annotations.Mojo;
@@ -46,6 +43,7 @@
 import org.springframework.boot.loader.tools.Layouts;
 import org.springframework.boot.loader.tools.Libraries;
 import org.springframework.boot.loader.tools.Repackager;
+import org.springframework.boot.loader.tools.Repackager.MainClassTimeoutWarningListener;
 
 /**
  * Repackages existing JAR and WAR archives so that they can be executed from the command
@@ -59,8 +57,6 @@
 @Mojo(name = "repackage", defaultPhase = LifecyclePhase.PACKAGE, requiresProject = true, threadSafe = true, requiresDependencyResolution = ResolutionScope.COMPILE_PLUS_RUNTIME, requiresDependencyCollection = ResolutionScope.COMPILE_PLUS_RUNTIME)
 public class RepackageMojo extends AbstractDependencyFilterMojo {
 
-	private static final long FIND_WARNING_TIMEOUT = TimeUnit.SECONDS.toMillis(10);
-
 	/**
 	 * The Maven project.
 	 * @since 1.0
@@ -224,7 +220,9 @@ private File getTargetFile() {
 	}
 
 	private Repackager getRepackager(File source) {
-		Repackager repackager = new LoggingRepackager(source, getLog());
+		Repackager repackager = new Repackager(source);
+		repackager.addMainClassTimeoutWarningListener(
+				new LoggingMainClassTimeoutWarningListener());
 		repackager.setMainClass(this.mainClass);
 		if (this.layout != null) {
 			getLog().info("Layout: " + this.layout);
@@ -356,30 +354,15 @@ public Layout layout() {
 
 	}
 
-	private static class LoggingRepackager extends Repackager {
-
-		private final Log log;
-
-		LoggingRepackager(File source, Log log) {
-			super(source);
-			this.log = log;
-		}
+	private class LoggingMainClassTimeoutWarningListener
+			implements MainClassTimeoutWarningListener {
 
 		@Override
-		protected String findMainMethod(JarFile source) throws IOException {
-			long startTime = System.currentTimeMillis();
-			try {
-				return super.findMainMethod(source);
-			}
-			finally {
-				long duration = System.currentTimeMillis() - startTime;
-				if (duration > FIND_WARNING_TIMEOUT) {
-					this.log.warn("Searching for the main-class is taking some time, "
-							+ "consider using the mainClass configuration "
-							+ "parameter");
-				}
-			}
+		public void handleTimeoutWarning(long duration, String mainMethod) {
+			getLog().warn("Searching for the main-class is taking some time, "
+					+ "consider using the mainClass configuration " + "parameter");
 		}
 
 	}
+
 }