Consistent fine-tuning of synchronized and concurrent data structures

In particular, avoiding synchronized Sets and Maps wherever possible (preferring a ConcurrentHashMap even instead of a synchronized Set) and specifying appropriate ConcurrentHashMap initial capacities (even if we end up choosing 16).

spring-test/src/main/java/org/springframework/mock/jndi/ExpectedLookupTemplate.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2009 the original author or authors.
+ * Copyright 2002-2012 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.
@@ -18,27 +18,26 @@ package org.springframework.mock.jndi;
 
 import java.util.Map;
 import java.util.concurrent.ConcurrentHashMap;
-
 import javax.naming.NamingException;
 
 import org.springframework.jndi.JndiTemplate;
 
 /**
- * Simple extension of the JndiTemplate class that always returns a given
- * object. Very useful for testing. Effectively a mock object.
- * 
+ * Simple extension of the JndiTemplate class that always returns a given object.
+ *
+ * <p>Very useful for testing. Effectively a mock object.
+ *
  * @author Rod Johnson
  * @author Juergen Hoeller
  */
 public class ExpectedLookupTemplate extends JndiTemplate {
 
-	private final Map<String, Object> jndiObjects = new ConcurrentHashMap<String, Object>();
+	private final Map<String, Object> jndiObjects = new ConcurrentHashMap<String, Object>(16);
 
 
 	/**
 	 * Construct a new JndiTemplate that will always return given objects for
 	 * given names. To be populated through <code>addObject</code> calls.
-	 * 
 	 * @see #addObject(String, Object)
 	 */
 	public ExpectedLookupTemplate() {
@@ -47,7 +46,6 @@ public class ExpectedLookupTemplate extends JndiTemplate {
 	/**
 	 * Construct a new JndiTemplate that will always return the given object,
 	 * but honour only requests for the given name.
-	 * 
 	 * @param name the name the client is expected to look up
 	 * @param object the object that will be returned
 	 */
@@ -56,9 +54,7 @@ public class ExpectedLookupTemplate extends JndiTemplate {
 	}
 
 	/**
-	 * Add the given object to the list of JNDI objects that this template will
-	 * expose.
-	 * 
+	 * Add the given object to the list of JNDI objects that this template will expose.
 	 * @param name the name the client is expected to look up
 	 * @param object the object that will be returned
 	 */

spring-test/src/main/java/org/springframework/test/context/ContextCache.java

@@ -44,7 +44,8 @@ class ContextCache {
 	/**
 	 * Map of context keys to Spring ApplicationContext instances.
 	 */
-	private final Map<MergedContextConfiguration, ApplicationContext> contextMap = new ConcurrentHashMap<MergedContextConfiguration, ApplicationContext>();
+	private final Map<MergedContextConfiguration, ApplicationContext> contextMap =
+			new ConcurrentHashMap<MergedContextConfiguration, ApplicationContext>(64);
 
 	private int hitCount;
 
@@ -69,7 +70,6 @@ class ContextCache {
 
 	/**
 	 * Return whether there is a cached context for the given key.
-	 *
 	 * @param key the context key (never <code>null</code>)
 	 */
 	boolean contains(MergedContextConfiguration key) {
@@ -79,10 +79,8 @@ class ContextCache {
 
 	/**
 	 * Obtain a cached ApplicationContext for the given key.
-	 *
 	 * <p>The {@link #getHitCount() hit} and {@link #getMissCount() miss}
 	 * counts will be updated accordingly.
-	 *
 	 * @param key the context key (never <code>null</code>)
 	 * @return the corresponding ApplicationContext instance,
 	 * or <code>null</code> if not found in the cache.
@@ -135,7 +133,6 @@ class ContextCache {
 
 	/**
 	 * Explicitly add an ApplicationContext instance to the cache under the given key.
-	 *
 	 * @param key the context key (never <code>null</code>)
 	 * @param context the ApplicationContext instance (never <code>null</code>)
 	 */
@@ -147,7 +144,6 @@ class ContextCache {
 
 	/**
 	 * Remove the context with the given key.
-	 *
 	 * @param key the context key (never <code>null</code>)
 	 * @return the corresponding ApplicationContext instance, or <code>null</code>
 	 * if not found in the cache.
@@ -162,11 +158,9 @@ class ContextCache {
 	 * {@link #remove removing} the context from the cache and explicitly
 	 * {@link ConfigurableApplicationContext#close() closing} it if it is an
 	 * instance of {@link ConfigurableApplicationContext}.
-	 *
 	 * <p>Generally speaking, you would only call this method if you change the
 	 * state of a singleton bean, potentially affecting future interaction with
 	 * the context.
-	 *
 	 * @param key the context key (never <code>null</code>)
 	 * @see #remove
 	 */
@@ -192,11 +186,8 @@ class ContextCache {
 	 * as the {@link #hitCount hit} and {@link #missCount miss} counts.
 	 */
 	public String toString() {
-		return new ToStringCreator(this)//
-		.append("size", size())//
-		.append("hitCount", getHitCount())//
-		.append("missCount", getMissCount())//
-		.toString();
+		return new ToStringCreator(this).append("size", size()).append("hitCount", getHitCount()).
+				append("missCount", getMissCount()).toString();
 	}
 
 }

spring-test/src/main/java/org/springframework/test/context/transaction/TransactionalTestExecutionListener.java

@@ -21,12 +21,13 @@ import java.lang.reflect.InvocationTargetException;
 import java.lang.reflect.Method;
 import java.util.ArrayList;
 import java.util.Collections;
-import java.util.IdentityHashMap;
 import java.util.List;
 import java.util.Map;
+import java.util.concurrent.ConcurrentHashMap;
 
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
+
 import org.springframework.beans.BeansException;
 import org.springframework.beans.factory.BeanFactory;
 import org.springframework.beans.factory.BeanFactoryUtils;
@@ -111,7 +112,7 @@ public class TransactionalTestExecutionListener extends AbstractTestExecutionLis
 	protected final TransactionAttributeSource attributeSource = new AnnotationTransactionAttributeSource();
 
 	private final Map<Method, TransactionContext> transactionContextCache =
-			Collections.synchronizedMap(new IdentityHashMap<Method, TransactionContext>());
+			new ConcurrentHashMap<Method, TransactionContext>(8);
 
 	private TransactionConfigurationAttributes configurationAttributes;