Improve ApplicationContextInitializer sorting

ContextLoader and FrameworkServlet now use
AnnotationAwareOrderComparator to support @Order usage; previously
supported only implementation of the Ordered interface.

org.springframework.context/src/main/java/org/springframework/context/ApplicationContextInitializer.java

@@ -27,16 +27,16 @@ package org.springframework.context;
  * for declaring a "contextInitializerClasses" context-param and init-param, respectively.
  *
  * <p>{@code ApplicationContextInitializer} processors are encouraged to detect
- * whether Spring's {@link org.springframework.core.Ordered Ordered} or
- * {@link org.springframework.core.PriorityOrdered PriorityOrdered} interfaces are also
- * implemented and sort instances accordingly if so prior to invocation.
+ * whether Spring's {@link org.springframework.core.Ordered Ordered} interface has been
+ * implemented or if the @{@link org.springframework.core.annotation.Order Order}
+ * annotation is present and to sort instances accordingly if so prior to invocation.
  *
  * @author Chris Beams
  * @since 3.1
  * @see org.springframework.web.context.ContextLoader#customizeContext
  * @see org.springframework.web.context.ContextLoader#CONTEXT_INITIALIZER_CLASSES_PARAM
  * @see org.springframework.web.servlet.FrameworkServlet#setContextInitializerClasses
- * @see org.springframework.web.servlet.FrameworkServlet#initializeWebApplicationContext
+ * @see org.springframework.web.servlet.FrameworkServlet#applyInitializers
  */
 public interface ApplicationContextInitializer<C extends ConfigurableApplicationContext> {
 

org.springframework.web.servlet/src/main/java/org/springframework/web/servlet/FrameworkServlet.java

@@ -18,7 +18,8 @@ package org.springframework.web.servlet;
 
 import java.io.IOException;
 import java.security.Principal;
-import java.util.TreeSet;
+import java.util.ArrayList;
+import java.util.Collections;
 
 import javax.servlet.ServletContext;
 import javax.servlet.ServletException;
@@ -184,8 +185,8 @@ public abstract class FrameworkServlet extends HttpServletBean {
 	private String contextInitializerClasses;
 
 	/** Actual ApplicationContextInitializer instances to apply to the context */
-	private TreeSet<ApplicationContextInitializer<ConfigurableApplicationContext>> contextInitializers =
-		new TreeSet<ApplicationContextInitializer<ConfigurableApplicationContext>>(new AnnotationAwareOrderComparator());
+	private ArrayList<ApplicationContextInitializer<ConfigurableApplicationContext>> contextInitializers =
+		new ArrayList<ApplicationContextInitializer<ConfigurableApplicationContext>>();
 
 
 	/**
@@ -652,6 +653,8 @@ public abstract class FrameworkServlet extends HttpServletBean {
 			}
 		}
 
+		Collections.sort(this.contextInitializers, new AnnotationAwareOrderComparator());
+
 		for (ApplicationContextInitializer<ConfigurableApplicationContext> initializer : this.contextInitializers) {
 			initializer.initialize(wac);
 		}

org.springframework.web/src/main/java/org/springframework/web/context/ContextLoader.java

@@ -18,6 +18,7 @@ package org.springframework.web.context;
 
 import java.io.IOException;
 import java.util.ArrayList;
+import java.util.Collections;
 import java.util.List;
 import java.util.Map;
 import java.util.Properties;
@@ -36,8 +37,8 @@ import org.springframework.context.ApplicationContextInitializer;
 import org.springframework.context.ConfigurableApplicationContext;
 import org.springframework.context.access.ContextSingletonBeanFactoryLocator;
 import org.springframework.core.GenericTypeResolver;
-import org.springframework.core.OrderComparator;
 import org.springframework.core.Ordered;
+import org.springframework.core.annotation.AnnotationAwareOrderComparator;
 import org.springframework.core.io.ClassPathResource;
 import org.springframework.core.io.support.PropertiesLoaderUtils;
 import org.springframework.util.Assert;
@@ -348,7 +349,7 @@ public class ContextLoader {
 				}
 				catch (ClassNotFoundException ex) {
 					throw new ApplicationContextException(
-							"Failed to load context configurer class [" + className + "]", ex);
+							"Failed to load context initializer class [" + className + "]", ex);
 				}
 			}
 		}
@@ -364,8 +365,9 @@ public class ContextLoader {
 	 * {@linkplain #CONTEXT_INITIALIZER_CLASSES_PARAM context init parameters} and
 	 * {@linkplain ApplicationContextInitializer#initialize invokes each} with the
 	 * given web application context.
-	 * <p>Any {@link Ordered} {@code ApplicationContextInitializer} will be sorted
-	 * appropriately.
+	 * <p>Any {@code ApplicationContextInitializers} implementing
+	 * {@link org.springframework.core.Ordered Ordered} or marked with @{@link
+	 * org.springframework.core.annotation.Order Order} will be sorted appropriately.
 	 * @param servletContext the current servlet context
 	 * @param applicationContext the newly created application context
 	 * @see #createWebApplicationContext(ServletContext, ApplicationContext)
@@ -373,7 +375,7 @@ public class ContextLoader {
 	 * @see ApplicationContextInitializer#initialize(ConfigurableApplicationContext)
 	 */
 	protected void customizeContext(ServletContext servletContext, ConfigurableWebApplicationContext applicationContext) {
-		List<ApplicationContextInitializer<ConfigurableApplicationContext>> initializerInstances =
+		ArrayList<ApplicationContextInitializer<ConfigurableApplicationContext>> initializerInstances =
 			new ArrayList<ApplicationContextInitializer<ConfigurableApplicationContext>>();
 
 		for (Class<ApplicationContextInitializer<ConfigurableApplicationContext>> initializerClass :
@@ -388,7 +390,7 @@ public class ContextLoader {
 			initializerInstances.add(BeanUtils.instantiateClass(initializerClass));
 		}
 
-		OrderComparator.sort(initializerInstances);
+		Collections.sort(initializerInstances, new AnnotationAwareOrderComparator());
 
 		for (ApplicationContextInitializer<ConfigurableApplicationContext> initializer : initializerInstances) {
 			initializer.initialize(applicationContext);