| // Copyright 2004 The Apache Software Foundation |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| |
| package org.apache.tapestry.util; |
| |
| import java.net.URL; |
| import java.util.Map; |
| |
| import org.apache.commons.logging.Log; |
| import org.apache.commons.logging.LogFactory; |
| import org.apache.tapestry.ApplicationRuntimeException; |
| import org.apache.tapestry.IResourceResolver; |
| import org.apache.tapestry.Tapestry; |
| |
| /** |
| * Default implementation of {@link org.apache.tapestry.IResourceResolver} based |
| * around {@link Thread#getContextClassLoader()} (which is set by the |
| * servlet container). |
| * |
| * @author Howard Lewis Ship |
| * @version $Id$ |
| * @since 2.3 |
| * |
| **/ |
| |
| public class DefaultResourceResolver implements IResourceResolver |
| { |
| private static final Log LOG = LogFactory.getLog(DefaultResourceResolver.class); |
| |
| private ClassLoader _loader; |
| |
| /** |
| * Constructs a new instance using |
| * {@link Thread#getContextClassLoader()}. |
| * |
| **/ |
| |
| public DefaultResourceResolver() |
| { |
| this(Thread.currentThread().getContextClassLoader()); |
| } |
| |
| public DefaultResourceResolver(ClassLoader loader) |
| { |
| _loader = loader; |
| } |
| |
| public URL getResource(String name) |
| { |
| boolean debug = LOG.isDebugEnabled(); |
| |
| if (debug) |
| LOG.debug("getResource(" + name + ")"); |
| |
| String stripped = removeLeadingSlash(name); |
| |
| URL result = _loader.getResource(stripped); |
| |
| if (debug) |
| { |
| if (result == null) |
| LOG.debug("Not found."); |
| else |
| LOG.debug("Found as " + result); |
| } |
| |
| return result; |
| } |
| |
| private String removeLeadingSlash(String name) |
| { |
| if (name.startsWith("/")) |
| return name.substring(1); |
| |
| return name; |
| } |
| |
| /** |
| * Invokes {@link Class#forName(java.lang.String, boolean, java.lang.ClassLoader)}. |
| * |
| * @param name the complete class name to locate and load |
| * @return The loaded class |
| * @throws ApplicationRuntimeException if loading the class throws an exception |
| * (typically {@link ClassNotFoundException} or a security exception) |
| * |
| **/ |
| |
| public Class findClass(String name) |
| { |
| try |
| { |
| return Class.forName(name, true, _loader); |
| } |
| catch (Throwable t) |
| { |
| throw new ApplicationRuntimeException( |
| Tapestry.format("ResourceResolver.unable-to-load-class", name, _loader, t.getMessage()), |
| t); |
| } |
| } |
| |
| /** |
| * |
| * OGNL Support for dynamic class loading. Simply invokes {@link #findClass(String)}. |
| * |
| **/ |
| |
| public Class classForName(String name, Map map) throws ClassNotFoundException |
| { |
| return findClass(name); |
| } |
| |
| /** @since 3.0 **/ |
| |
| public ClassLoader getClassLoader() |
| { |
| return _loader; |
| } |
| |
| } |