package com.quickwebframework.viewrender.velocity.util;
import java.io.BufferedInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.URL;
import java.util.Collections;
import java.util.HashMap;
import java.util.Map;
import org.apache.commons.collections.ExtendedProperties;
import org.apache.velocity.exception.ResourceNotFoundException;
import org.apache.velocity.exception.VelocityException;
import org.apache.velocity.runtime.resource.Resource;
import org.apache.velocity.runtime.resource.loader.ResourceLoader;
import org.osgi.framework.Bundle;
import com.quickwebframework.framework.OsgiContext;
public class BundleResourceLoader extends ResourceLoader {
// 用来缓存已经找到的视图名称与插件
private Map<String, Bundle> templateBundles = Collections
.synchronizedMap(new HashMap<String, Bundle>());
private String pluginNameAndPathSplitString;
private String viewNameSuffix;
private String viewNamePrefix;
@Override
public long getLastModified(Resource resource) {
Bundle bundle = templateBundles.get(resource.getName());
if (bundle == null) {
return 0;
} else {
return bundle.getLastModified();
}
}
@Override
public InputStream getResourceStream(String name)
throws ResourceNotFoundException {
if ("VM_global_library.vm".equals(name)) {
return null;
}
String[] tmpArray = name.split(pluginNameAndPathSplitString);
if (tmpArray.length < 2) {
throw new VelocityException("视图名称[" + name + "]不符合规则：“[插件名]"
+ pluginNameAndPathSplitString + "[路径]”");
}
String pluginName = tmpArray[0];
String path = tmpArray[1];
// 对视图名称进行处理(添加前后缀)
path = viewNamePrefix + path + viewNameSuffix;
Bundle bundle = OsgiContext.getBundleByName(pluginName);
if (bundle == null) {
throw new VelocityException(String.format(
"Can't found plugin[%s],template [%s] load failure.",
pluginName, name));
}
URL url = bundle.getResource(path);
if (url == null) {
throw new ResourceNotFoundException(
"BundleResourceLoader : cannot find " + name);
}
InputStream ufs;
try {
ufs = url.openStream();
} catch (IOException ioe) {
String msg = "Exception while loading Template " + name;
log.error(msg, ioe);
throw new VelocityException(msg, ioe);
}
templateBundles.put(name, bundle);
return new BufferedInputStream(ufs);
}
@Override
public void init(ExtendedProperties arg0) {
this.pluginNameAndPathSplitString = arg0
.getString("class.pluginNameAndPathSplitString");
this.viewNamePrefix = arg0.getString("class.viewNamePrefix");
this.viewNameSuffix = arg0.getString("class.viewNameSuffix");
}
@Override
public boolean isSourceModified(Resource resource) {
long lastModified = getLastModified(resource);
return lastModified != resource.getLastModified();
}
}