Admin: 1 версия

2010-06-01T07:07:20Z

1 версия

в 18:01, 31 мая 2010

2010-05-31T18:01:46Z

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== Caching Class path Resource Loader ==



<source lang="java">

import java.io.IOException;
import java.io.InputStream;
import java.net.URL;
import java.util.HashMap;
import java.util.Map;
import org.apache.rumons.collections.ExtendedProperties;
import org.apache.velocity.exception.ResourceNotFoundException;
import org.apache.velocity.runtime.resource.Resource;
import org.apache.velocity.runtime.resource.loader.ResourceLoader;
public class CachingClasspathResourceLoader extends ResourceLoader {
private Map urlMap = new HashMap();
public void init(ExtendedProperties configuration) {
}
public synchronized InputStream getResourceStream(String resourceName)
throws ResourceNotFoundException {
try {
URL url = getURL(resourceName);
if (url == null) {
throw new ResourceNotFoundException("Can not find resource: "
+ resourceName);
}
return url.openStream();
} catch (IOException e) {
throw new ResourceNotFoundException("Can not find resource: "
+ resourceName + " - Reason: " + e.getMessage());
}
}
public long getLastModified(Resource res) {
try {
URL url = getURL(res.getName());
long lm = url.openConnection().getLastModified();
return lm;
} catch (Exception e) {
rsvc.error(e);
return 0;
}
}
public boolean isSourceModified(Resource res) {
long lastModified = getLastModified(res);
return (lastModified != res.getLastModified());
}
private URL getURL(String rn) {
if (urlMap.containsKey(rn)) {
return (URL) urlMap.get(rn);
}
ClassLoader cl = this.getClass().getClassLoader();
URL url = cl.getResource(rn);
if (url != null) {
urlMap.put(rn, url);
}
return url;
}
}

</source>



== Resource Loader Demo ==



<source lang="java">

import java.io.StringWriter;
import java.io.Writer;
import org.apache.velocity.Template;
import org.apache.velocity.VelocityContext;
import org.apache.velocity.app.Velocity;
public class ResourceLoaders {
private static final String FILE_RESOURCE_LOADER_TEMPLATE = "./src/ResourceLoader1.vm";
private static final String JAR_RESOURCE_LOADER_TEMPLATE = "./src/ResourceLoader2.vm";
private static final String CLASSPATH_RESOURCE_LOADER_TEMPLATE = "./src/ResourceLoader3.vm";
public static void main(String[] args) throws Exception {
processTemplate(FILE_RESOURCE_LOADER_TEMPLATE);
processTemplate(FILE_RESOURCE_LOADER_TEMPLATE);
processTemplate(JAR_RESOURCE_LOADER_TEMPLATE);
processTemplate(JAR_RESOURCE_LOADER_TEMPLATE);
processTemplate(CLASSPATH_RESOURCE_LOADER_TEMPLATE);
processTemplate(CLASSPATH_RESOURCE_LOADER_TEMPLATE);
}
private static void processTemplate(String templateName) throws Exception {
Velocity.init();
Template template = Velocity.getTemplate(templateName);
VelocityContext context = new VelocityContext();
Writer writer = new StringWriter();
template.merge(context, writer);
System.out.println(writer.toString());
}
}
-------------------------------------------------------------------------------------
//File: ResourceLoader1.vm
ResourceLoader1 Template!
//File: ResourceLoader2.vm
ResourceLoader2 Template Modified!

//File: ResourceLoader3.vm
ResourceLoader3 Template 3

</source>

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Java/Velocity/Resource Loader - История изменений

Admin: 1 версия

в 18:01, 31 мая 2010