DecoratingClassLoader and its subclasses register themselves as parallel capable on Java 7+

Issue: SPR-12285

Author: jhoeller

spring-context/src/main/java/org/springframework/context/support/ContextTypeMatchClassLoader.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2012 the original author or authors.
+ * Copyright 2002-2014 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -17,12 +17,13 @@
 package org.springframework.context.support;
 
 import java.lang.reflect.Method;
-import java.util.HashMap;
 import java.util.Map;
+import java.util.concurrent.ConcurrentHashMap;
 
 import org.springframework.core.DecoratingClassLoader;
 import org.springframework.core.OverridingClassLoader;
 import org.springframework.core.SmartClassLoader;
+import org.springframework.lang.UsesJava7;
 import org.springframework.util.ReflectionUtils;
 
 /**
@@ -36,13 +37,21 @@
  * @see AbstractApplicationContext
  * @see org.springframework.beans.factory.config.ConfigurableBeanFactory#setTempClassLoader
  */
+@UsesJava7
 class ContextTypeMatchClassLoader extends DecoratingClassLoader implements SmartClassLoader {
 
+	static {
+		if (parallelCapableClassLoaderAvailable) {
+			ClassLoader.registerAsParallelCapable();
+		}
+	}
+
+
 	private static Method findLoadedClassMethod;
 
 	static {
 		try {
-			findLoadedClassMethod = ClassLoader.class.getDeclaredMethod("findLoadedClass", new Class<?>[] {String.class});
+			findLoadedClassMethod = ClassLoader.class.getDeclaredMethod("findLoadedClass", String.class);
 		}
 		catch (NoSuchMethodException ex) {
 			throw new IllegalStateException("Invalid [java.lang.ClassLoader] class: no 'findLoadedClass' method defined!");
@@ -51,7 +60,7 @@ class ContextTypeMatchClassLoader extends DecoratingClassLoader implements Smart
 
 
 	/** Cache for byte array per class name */
-	private final Map<String, byte[]> bytesCache = new HashMap<String, byte[]>();
+	private final Map<String, byte[]> bytesCache = new ConcurrentHashMap<String, byte[]>(256);
 
 
 	public ContextTypeMatchClassLoader(ClassLoader parent) {

spring-context/src/main/java/org/springframework/instrument/classloading/SimpleInstrumentableClassLoader.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2012 the original author or authors.
+ * Copyright 2002-2014 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -19,6 +19,7 @@
 import java.lang.instrument.ClassFileTransformer;
 
 import org.springframework.core.OverridingClassLoader;
+import org.springframework.lang.UsesJava7;
 
 /**
  * Simplistic implementation of an instrumentable {@code ClassLoader}.
@@ -29,16 +30,22 @@
  * @author Costin Leau
  * @since 2.0
  */
+@UsesJava7
 public class SimpleInstrumentableClassLoader extends OverridingClassLoader {
 
+	static {
+		if (parallelCapableClassLoaderAvailable) {
+			ClassLoader.registerAsParallelCapable();
+		}
+	}
+
+
 	private final WeavingTransformer weavingTransformer;
 
 
 	/**
-	 * Create a new {@code SimpleLoadTimeWeaver} for the given
-	 * {@code ClassLoader}.
-	 * @param parent the {@code ClassLoader} to build a simple
-	 * instrumentable {@code ClassLoader} for
+	 * Create a new SimpleInstrumentableClassLoader for the given ClassLoader.
+	 * @param parent the ClassLoader to build an instrumentable ClassLoader for
 	 */
 	public SimpleInstrumentableClassLoader(ClassLoader parent) {
 		super(parent);
@@ -47,9 +54,8 @@ public SimpleInstrumentableClassLoader(ClassLoader parent) {
 
 
 	/**
-	 * Add a {@code ClassFileTransformer} to be applied by this
-	 * {@code ClassLoader}.
-	 * @param transformer the {@code ClassFileTransformer} to register
+	 * Add a {@link ClassFileTransformer} to be applied by this ClassLoader.
+	 * @param transformer the {@link ClassFileTransformer} to register
 	 */
 	public void addTransformer(ClassFileTransformer transformer) {
 		this.weavingTransformer.addTransformer(transformer);

spring-context/src/main/java/org/springframework/instrument/classloading/SimpleThrowawayClassLoader.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2006 the original author or authors.
+ * Copyright 2002-2014 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -17,6 +17,7 @@
 package org.springframework.instrument.classloading;
 
 import org.springframework.core.OverridingClassLoader;
+import org.springframework.lang.UsesJava7;
 
 /**
  * ClassLoader that can be used to load classes without bringing them
@@ -26,10 +27,18 @@
  * @author Rod Johnson
  * @since 2.0
  */
+@UsesJava7
 public class SimpleThrowawayClassLoader extends OverridingClassLoader {
 
+	static {
+		if (parallelCapableClassLoaderAvailable) {
+			ClassLoader.registerAsParallelCapable();
+		}
+	}
+
+
 	/**
-	 * Create a new SimpleThrowawayClassLoader for the given class loader.
+	 * Create a new SimpleThrowawayClassLoader for the given ClassLoader.
 	 * @param parent the ClassLoader to build a throwaway ClassLoader for
 	 */
 	public SimpleThrowawayClassLoader(ClassLoader parent) {

spring-core/src/main/java/org/springframework/core/DecoratingClassLoader.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2008 the original author or authors.
+ * Copyright 2002-2014 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -19,7 +19,9 @@
 import java.util.HashSet;
 import java.util.Set;
 
+import org.springframework.lang.UsesJava7;
 import org.springframework.util.Assert;
+import org.springframework.util.ClassUtils;
 
 /**
  * Base class for decorating ClassLoaders such as {@link OverridingClassLoader}
@@ -30,8 +32,23 @@
  * @author Rod Johnson
  * @since 2.5.2
  */
+@UsesJava7
 public abstract class DecoratingClassLoader extends ClassLoader {
 
+	/**
+	 * Java 7+ {@code ClassLoader.registerAsParallelCapable()} available?
+	 * @since 4.1.2
+	 */
+	protected static final boolean parallelCapableClassLoaderAvailable =
+			ClassUtils.hasMethod(ClassLoader.class, "registerAsParallelCapable");
+
+	static {
+		if (parallelCapableClassLoaderAvailable) {
+			ClassLoader.registerAsParallelCapable();
+		}
+	}
+
+
 	private final Set<String> excludedPackages = new HashSet<String>();
 
 	private final Set<String> excludedClasses = new HashSet<String>();

spring-core/src/main/java/org/springframework/core/OverridingClassLoader.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2012 the original author or authors.
+ * Copyright 2002-2014 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -19,6 +19,7 @@
 import java.io.IOException;
 import java.io.InputStream;
 
+import org.springframework.lang.UsesJava7;
 import org.springframework.util.FileCopyUtils;
 
 /**
@@ -33,17 +34,23 @@
  * @author Juergen Hoeller
  * @since 2.0.1
  */
+@UsesJava7
 public class OverridingClassLoader extends DecoratingClassLoader {
 
 	/** Packages that are excluded by default */
-	public static final String[] DEFAULT_EXCLUDED_PACKAGES =
-			new String[] {"java.", "javax.", "sun.", "oracle."};
+	public static final String[] DEFAULT_EXCLUDED_PACKAGES = new String[] {"java.", "javax.", "sun.", "oracle."};
 
 	private static final String CLASS_FILE_SUFFIX = ".class";
 
+	static {
+		if (parallelCapableClassLoaderAvailable) {
+			ClassLoader.registerAsParallelCapable();
+		}
+	}
+
 
 	/**
-	 * Create a new OverridingClassLoader for the given class loader.
+	 * Create a new OverridingClassLoader for the given ClassLoader.
 	 * @param parent the ClassLoader to build an overriding ClassLoader for
 	 */
 	public OverridingClassLoader(ClassLoader parent) {