optional EL support (only when Tiles EL module present); got rid of tiles-servlet-wildcard dependency (implemented wildcard support locally)

Author: jhoeller

org.springframework.web.servlet/src/main/java/org/springframework/web/servlet/view/tiles2/SpringTilesApplicationContextFactory.java

@@ -16,15 +16,23 @@
 
 package org.springframework.web.servlet.view.tiles2;
 
+import java.io.IOException;
+import java.net.URL;
 import java.util.Enumeration;
+import java.util.HashSet;
 import java.util.LinkedHashMap;
 import java.util.Map;
+import java.util.Set;
 import javax.servlet.ServletContext;
 
 import org.apache.tiles.Initializable;
 import org.apache.tiles.TilesApplicationContext;
 import org.apache.tiles.context.AbstractTilesApplicationContextFactory;
-import org.apache.tiles.servlet.context.wildcard.WildcardServletTilesApplicationContext;
+import org.apache.tiles.servlet.context.ServletTilesApplicationContext;
+
+import org.springframework.core.io.Resource;
+import org.springframework.core.io.support.ResourcePatternResolver;
+import org.springframework.web.context.support.ServletContextResourcePatternResolver;
 
 /**
  * Spring-specific subclass of the standard Tiles AbstractTilesApplicationContextFactory,
@@ -52,10 +60,12 @@ public TilesApplicationContext createApplicationContext(Object context) {
 	 * Custom subclass of the standard Tiles WildcardServletTilesApplicationContext,
 	 * passing given properties through as Tiles init-param map.
 	 */
-	private static class SpringWildcardServletTilesApplicationContext extends WildcardServletTilesApplicationContext {
+	private static class SpringWildcardServletTilesApplicationContext extends ServletTilesApplicationContext {
 
 		private final Map<String, String> mergedInitParams;
 
+		private final ResourcePatternResolver resolver;
+
 		public SpringWildcardServletTilesApplicationContext(ServletContext servletContext, Map<String, String> params) {
 			super(servletContext);
 			this.mergedInitParams = new LinkedHashMap<String, String>();
@@ -67,12 +77,36 @@ public SpringWildcardServletTilesApplicationContext(ServletContext servletContex
 			if (params != null) {
 				this.mergedInitParams.putAll(params);
 			}
+			this.resolver = new ServletContextResourcePatternResolver(servletContext);
 		}
 
 		@Override
 		public Map<String, String> getInitParams() {
 			return this.mergedInitParams;
 		}
+
+		@Override
+		public URL getResource(String path) throws IOException {
+			URL retValue = null;
+			Set<URL> urlSet = getResources(path);
+			if (urlSet != null && !urlSet.isEmpty()) {
+				retValue = urlSet.iterator().next();
+			}
+			return retValue;
+		}
+
+		@Override
+		public Set<URL> getResources(String path) throws IOException {
+			Set<URL> urlSet = null;
+			Resource[] resources = this.resolver.getResources(path);
+			if (resources != null && resources.length > 0) {
+				urlSet = new HashSet<URL>();
+				for (Resource resource : resources) {
+					urlSet.add(resource.getURL());
+				}
+			}
+			return urlSet;
+		}
 	}
 
 }

org.springframework.web.servlet/src/main/java/org/springframework/web/servlet/view/tiles2/TilesConfigurer.java

@@ -62,14 +62,14 @@
 import org.springframework.web.context.ServletContextAware;
 
 /**
- * Helper class to configure Tiles2 for the Spring Framework. See
+ * Helper class to configure Tiles 2.x for the Spring Framework. See
  * <a href="http://tiles.apache.org">http://tiles.apache.org</a>
  * for more information about Tiles, which basically is a templating
  * mechanism for JSP-based web applications.
  *
  * <b>Note: Spring 3.0 requires Tiles 2.1.2 or above, with explicit support for Tiles 2.2.</b>
- * Tiles 2.1's EL support will be activated by default when running on JSP 2.1 or above.
- * Note that EL support is <i>not</> active by default when running against Tiles 2.2.
+ * Tiles 2.1's EL support will be activated by default when running on JSP 2.1 or above
+ * and when the Tiles EL module is present in the classpath.
  *
  * <p>The TilesConfigurer simply configures a TilesContainer using a set of files
  * containing definitions, to be accessed by {@link TilesView} instances. This is a
@@ -103,8 +103,11 @@
  */
 public class TilesConfigurer implements ServletContextAware, InitializingBean, DisposableBean {
 
-	private static final boolean jsp21Present = ClassUtils.isPresent(
-			"javax.servlet.jsp.JspApplicationContext", TilesConfigurer.class.getClassLoader());
+	private static final boolean tilesElPresent =  // requires JSP 2.1 as well as Tiles EL module
+			ClassUtils.isPresent(
+			"javax.servlet.jsp.JspApplicationContext", TilesConfigurer.class.getClassLoader()) &&
+			ClassUtils.isPresent(
+			"org.apache.tiles.evaluator.el.ELAttributeEvaluator", TilesConfigurer.class.getClassLoader());
 
 	private static final boolean tiles22Present = ClassUtils.isPresent(
 			"org.apache.tiles.evaluator.AttributeEvaluatorFactory", TilesConfigurer.class.getClassLoader());
@@ -140,8 +143,8 @@ public TilesConfigurer() {
 				Boolean.toString(false));
 		this.tilesPropertyMap.put(DefinitionsFactory.LOCALE_RESOLVER_IMPL_PROPERTY,
 				SpringLocaleResolver.class.getName());
-		this.tilesPropertyMap.put(TilesContainerFactory.ATTRIBUTE_EVALUATOR_INIT_PARAM,
-				jsp21Present ? ELAttributeEvaluator.class.getName() : DirectAttributeEvaluator.class.getName());
+		this.tilesPropertyMap.put(TilesContainerFactory.ATTRIBUTE_EVALUATOR_INIT_PARAM, tilesElPresent ?
+				"org.apache.tiles.evaluator.el.ELAttributeEvaluator" : DirectAttributeEvaluator.class.getName());
 	}
 
 
@@ -308,25 +311,12 @@ public void afterPropertiesSet() throws TilesException {
 			}
 		}
 
-		if (jsp21Present && this.tilesInitializer instanceof SpringTilesInitializer) {
+		if (tilesElPresent && this.tilesInitializer instanceof SpringTilesInitializer) {
 			// Again, we need to do this after initialization since SpringTilesContainerFactory
 			// cannot override template methods that refer to Tiles 2.2 classes: in this case,
 			// AttributeEvaluatorFactory as createAttributeEvaluatorFactory return type.
-			try {
-				BasicTilesContainer container = (BasicTilesContainer) ServletUtil.getContainer(this.servletContext);
-				Class aef = getClass().getClassLoader().loadClass("org.apache.tiles.evaluator.AttributeEvaluatorFactory");
-				Class baef = getClass().getClassLoader().loadClass("org.apache.tiles.evaluator.BasicAttributeEvaluatorFactory");
-				Constructor baefCtor = baef.getConstructor(AttributeEvaluator.class);
-				ELAttributeEvaluator evaluator = new ELAttributeEvaluator();
-				evaluator.setApplicationContext(container.getApplicationContext());
-				evaluator.init(new HashMap<String, String>());
-				Object baefValue = baefCtor.newInstance(evaluator);
-				Method setter = container.getClass().getMethod("setAttributeEvaluatorFactory", aef);
-				setter.invoke(container, baefValue);
-			}
-			catch (Exception ex) {
-				throw new IllegalStateException("Cannot activate ELAttributeEvaluator", ex);
-			}
+			BasicTilesContainer container = (BasicTilesContainer) ServletUtil.getContainer(this.servletContext);
+			TilesElActivator.registerEvaluator(container);
 		}
 	}
 
@@ -432,4 +422,26 @@ protected PreparerFactory createPreparerFactory(TilesApplicationContext applicat
 		}
 	}
 
+
+	private static class TilesElActivator {
+
+		public static void registerEvaluator(BasicTilesContainer container) {
+			try {
+				ClassLoader cl = TilesElActivator.class.getClassLoader();
+				Class aef = cl.loadClass("org.apache.tiles.evaluator.AttributeEvaluatorFactory");
+				Class baef = cl.loadClass("org.apache.tiles.evaluator.BasicAttributeEvaluatorFactory");
+				Constructor baefCtor = baef.getConstructor(AttributeEvaluator.class);
+				ELAttributeEvaluator evaluator = new ELAttributeEvaluator();
+				evaluator.setApplicationContext(container.getApplicationContext());
+				evaluator.init(new HashMap<String, String>());
+				Object baefValue = baefCtor.newInstance(evaluator);
+				Method setter = container.getClass().getMethod("setAttributeEvaluatorFactory", aef);
+				setter.invoke(container, baefValue);
+			}
+			catch (Exception ex) {
+				throw new IllegalStateException("Cannot activate ELAttributeEvaluator", ex);
+			}
+		}
+	}
+
 }