/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You 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.nutch.webapp.common;
import java.util.Collection;
import java.util.Collections;
import java.util.HashMap;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.conf.Configuration;
import org.apache.nutch.plugin.Extension;
import org.apache.nutch.plugin.ExtensionPoint;
import org.apache.nutch.webapp.extension.PostSearchExtensionPoint;
import org.apache.nutch.webapp.extension.PreSearchExtensionPoint;
import org.apache.nutch.webapp.extension.SearchExtensionPoint;
public class BaseSearch {
public static final Log LOG = LogFactory.getLog(BaseSearch.class);
protected PreSearchExtensionPoint[] presearch;
protected SearchExtensionPoint[] search;
protected PostSearchExtensionPoint[] postsearch;
protected Collection setup(String xPoint, Configuration conf) {
LOG.info("setting up:" + xPoint);
HashMap filters = new HashMap();
try {
ExtensionPoint point = serviceLocator.getPluginRepository()
.getExtensionPoint(xPoint);
if (point != null) {
Extension[] extensions = point.getExtensions();
for (int i = 0; i < extensions.length; i++) {
Extension extension = extensions[i];
Object extensionInstance = extension.getExtensionInstance();
if (!filters.containsKey(extensionInstance.getClass().getName())) {
filters.put(extensionInstance.getClass().getName(),
extensionInstance);
}
}
return filters.values();
}
} catch (Exception e) {
LOG.info("Error setting up extensions :" + e);
}
return Collections.EMPTY_LIST;
}
private ServiceLocator serviceLocator;
/**
* Construct new BaseSearch object
*/
public BaseSearch(ServiceLocator locator) {
this.serviceLocator = locator;
Collection pre = getPreSearchExtensions(serviceLocator.getConfiguration());
presearch = new PreSearchExtensionPoint[pre.size()];
pre.toArray(presearch);
Collection searchC = getSearchExtensions(serviceLocator.getConfiguration());
search = new SearchExtensionPoint[searchC.size()];
searchC.toArray(search);
Collection post = getPostSearchExtensions(serviceLocator.getConfiguration());
postsearch = new PostSearchExtensionPoint[post.size()];
post.toArray(postsearch);
}
public Collection getPreSearchExtensions(Configuration conf) {
if (conf.getObject(PreSearchExtensionPoint.X_POINT_ID) == null) {
conf.setObject(PreSearchExtensionPoint.X_POINT_ID, setup(
PreSearchExtensionPoint.X_POINT_ID, conf));
}
return (Collection) conf.getObject(PreSearchExtensionPoint.X_POINT_ID);
}
public Collection getSearchExtensions(Configuration conf) {
if (conf.getObject(SearchExtensionPoint.X_POINT_ID) == null) {
conf.setObject(SearchExtensionPoint.X_POINT_ID, setup(
SearchExtensionPoint.X_POINT_ID, conf));
}
return (Collection) conf.getObject(SearchExtensionPoint.X_POINT_ID);
}
public Collection getPostSearchExtensions(Configuration conf) {
if (conf.getObject(PostSearchExtensionPoint.X_POINT_ID) == null) {
conf.setObject(PostSearchExtensionPoint.X_POINT_ID, setup(
PostSearchExtensionPoint.X_POINT_ID, conf));
}
return (Collection) conf.getObject(PostSearchExtensionPoint.X_POINT_ID);
}
/**
* Call plugins participating PreSearch activities.
*/
void callPreSearch(ServiceLocator locator) {
LOG.info("presearch");
for (int i = 0; i < presearch.length; i++) {
presearch[i].doPreSearch(serviceLocator);
}
}
/**
* Call plugins participating Search activities.
*/
void callSearch() {
for (int i = 0; i < search.length; i++) {
search[i].doSearch(serviceLocator);
}
}
/**
* Call plugins participating postSearch activities.
*/
void callPostSearch(ServiceLocator locator) {
LOG.info("postsearch");
for (int i = 0; i < postsearch.length; i++) {
postsearch[i].doPostSearch(serviceLocator);
}
}
/**
* Entry point to execute the search.
*/
public void doSearch() {
// create context
callPreSearch(serviceLocator);
serviceLocator.getSearch().performSearch();
// callSearch();
callPostSearch(serviceLocator);
}
}