Simple loader to get templates from the resources in the classpath.
Exceptionally useful, I think, for servlet use on a v2.2 or better
servlet container - you just jar up your templates any way you want
and drop them into WEB-INF/lib, and that's it. No configuration
files to worry about, nor do you have to manually set the root of
your template paths at runtime, so you webapp is easily portable
w/o extra work.
Tested with Tomcat 3.2.1 - should be fine with Catalina as well.
Also tested with jars explicitly placed in the classpath (yech) as well
as simply adding the template-containing directory to the classpath
(yech also).
But it works.
PR:
Obtained from:
Submitted by:
Reviewed by:
git-svn-id: https://svn.apache.org/repos/asf/jakarta/velocity/trunk@74382 13f79535-47bb-0310-9956-ffa450edef68
diff --git a/src/java/org/apache/velocity/runtime/resource/loader/ClasspathResourceLoader.java b/src/java/org/apache/velocity/runtime/resource/loader/ClasspathResourceLoader.java
new file mode 100644
index 0000000..2441799
--- /dev/null
+++ b/src/java/org/apache/velocity/runtime/resource/loader/ClasspathResourceLoader.java
@@ -0,0 +1,175 @@
+package org.apache.velocity.runtime.resource.loader;
+
+/*
+ * The Apache Software License, Version 1.1
+ *
+ * Copyright (c) 2001 The Apache Software Foundation. All rights
+ * reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in
+ * the documentation and/or other materials provided with the
+ * distribution.
+ *
+ * 3. The end-user documentation included with the redistribution, if
+ * any, must include the following acknowlegement:
+ * "This product includes software developed by the
+ * Apache Software Foundation (http://www.apache.org/)."
+ * Alternately, this acknowlegement may appear in the software itself,
+ * if and wherever such third-party acknowlegements normally appear.
+ *
+ * 4. The names "The Jakarta Project", "Tomcat", and "Apache Software
+ * Foundation" must not be used to endorse or promote products derived
+ * from this software without prior written permission. For written
+ * permission, please contact apache@apache.org.
+ *
+ * 5. Products derived from this software may not be called "Apache"
+ * nor may "Apache" appear in their names without prior written
+ * permission of the Apache Group.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ * ====================================================================
+ *
+ * This software consists of voluntary contributions made by many
+ * individuals on behalf of the Apache Software Foundation. For more
+ * information on the Apache Software Foundation, please see
+ * <http://www.apache.org/>.
+ */
+
+import java.io.InputStream;
+
+import org.apache.velocity.runtime.Runtime;
+import org.apache.velocity.runtime.resource.Resource;
+import org.apache.velocity.exception.ResourceNotFoundException;
+import org.apache.velocity.runtime.configuration.Configuration;
+
+/**
+ * ClasspathResourceLoader is a simple loader that will load
+ * templates from the classpath.
+ * <br>
+ * <br>
+ * Will load templates from from multiple instances of
+ * and arbitrary combinations of :
+ * <ul>
+ * <li> jar files
+ * <li> zip files
+ * <li> template directories (any directory containing templates)
+ * </ul>
+ * This is a configuration-free loader, in that there are no
+ * parameters to be specified in the configuration properties,
+ * other than specifying this as the loader to use. For example
+ * the following is all that the loader needs to be functional :
+ * <br>
+ * <br>
+ * resource.loader.1.class =
+ * org.apache.velocity.runtime.resource.loader.ClasspathResourceLoader
+ * <br>
+ * <br>
+ * To use, put your template directories, jars
+ * and zip files into the classpath or other mechanisms that make
+ * resources accessable to the classloader.
+ * <br>
+ * <br>
+ * This makes deployment trivial for web applications running in
+ * any Servlet 2.2 compliant servlet runner, such as Tomcat 3.2
+ * and others.
+ * <br>
+ * <br>
+ * For a Servlet Spec v2.2 servlet runner,
+ * just drop the jars of template files into the WEB-INF/lib
+ * directory of your webapp, and you won't have to worry about setting
+ * template paths or altering them with the root of the webapp
+ * before initializing.
+ * <br>
+ * <br>
+ * I have also tried it with a WAR deployment, and that seemed to
+ * work just fine.
+ *
+ * @author <a href="mailto:geirm@optonline.net">Geir Magnusson Jr.</a>
+ * @version $Id: ClasspathResourceLoader.java,v 1.1 2001/03/05 02:59:28 geirm Exp $
+ */
+public class ClasspathResourceLoader extends ResourceLoader
+{
+
+ /**
+ * This is abstract in the base class, so we need it
+ */
+ public void init(Configuration configuration)
+ {
+ }
+
+ /**
+ * Get an InputStream so that the Runtime can build a
+ * template with it.
+ *
+ * @param name name of template to get
+ * @return InputStream containing the template
+ * @throws ResourceNotFoundException if template not found
+ * in classpath.
+ */
+ public synchronized InputStream getResourceStream( String name )
+ throws ResourceNotFoundException
+ {
+ InputStream result = null;
+
+ if (name == null || name.length() == 0)
+ {
+ throw new ResourceNotFoundException ("No template name provided");
+ }
+
+ try
+ {
+ ClassLoader classLoader = this.getClass().getClassLoader();
+ result= classLoader.getResourceAsStream( name );
+ }
+ catch( Exception fnfe )
+ {
+ /*
+ * log and convert to a general Velocity ResourceNotFoundException
+ */
+
+ Runtime.error("ClasspathResourceLoader Error : exception : " + fnfe );
+ throw new ResourceNotFoundException( fnfe.getMessage() );
+ }
+
+ return result;
+ }
+
+ public boolean isSourceModified(Resource resource)
+ {
+ return false;
+ }
+
+ public long getLastModified(Resource resource)
+ {
+ return 0;
+ }
+}
+
+
+
+
+
+
+
+
+
+
