org.apache.hadoop.chukwa.datastore.WidgetStore.java Source code

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Here is the source code for org.apache.hadoop.chukwa.datastore.WidgetStore.java

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/*
 * 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.hadoop.chukwa.datastore;

import java.io.File;
import java.io.IOException;
import java.util.HashMap;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.json.JSONObject;

import org.apache.hadoop.chukwa.conf.ChukwaConfiguration;
import org.apache.hadoop.chukwa.hicc.HiccWebServer;
import org.apache.hadoop.chukwa.rest.bean.CatalogBean;
import org.apache.hadoop.chukwa.rest.bean.WidgetBean;
import org.apache.hadoop.chukwa.util.ExceptionUtil;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FSDataInputStream;
import org.apache.hadoop.fs.FSDataOutputStream;
import org.apache.hadoop.fs.FileStatus;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;

public class WidgetStore {
    private static Log log = LogFactory.getLog(WidgetStore.class);
    private static Configuration config = new Configuration();
    private static ChukwaConfiguration chukwaConf = new ChukwaConfiguration();
    private static String hiccPath = config.get("fs.default.name") + File.separator
            + chukwaConf.get("chukwa.data.dir") + File.separator + "hicc" + File.separator + "widgets";
    private static CatalogBean catalog = null;
    private static HashMap<String, WidgetBean> list = new HashMap<String, WidgetBean>();

    public WidgetStore() throws IllegalAccessException {
        WidgetStore.config = HiccWebServer.getConfig();
    }

    public void set(WidgetBean widget) throws IllegalAccessException {
        try {
            StringBuilder widgetPath = new StringBuilder();
            widgetPath.append(hiccPath);
            widgetPath.append(File.separator);
            widgetPath.append(widget.getId());
            widgetPath.append(".descriptor");
            Path widgetFile = new Path(widgetPath.toString());
            FileSystem fs;
            try {
                fs = FileSystem.get(config);
                FSDataOutputStream out = fs.create(widgetFile, true);
                out.writeUTF(widget.deserialize().toString());
                out.close();
            } catch (IOException ex) {
                log.error(ExceptionUtil.getStackTrace(ex));
            }
            cacheWidgets();
        } catch (Exception e) {
            log.error(ExceptionUtil.getStackTrace(e));
            throw new IllegalAccessException("Unable to access user view database.");
        }
    }

    public static void cacheWidgets() throws IllegalAccessException {
        StringBuilder widgetPath = new StringBuilder();
        widgetPath.append(hiccPath);
        Path widgetFiles = new Path(widgetPath.toString());
        FileSystem fs;
        catalog = new CatalogBean();
        catalog.setId("root");
        catalog.setLabel("root");
        try {
            fs = FileSystem.get(config);
            FileStatus[] fstatus = fs.listStatus(widgetFiles);
            if (fstatus != null) {
                for (int i = 0; i < fstatus.length; i++) {
                    long size = fstatus[i].getLen();
                    FSDataInputStream widgetStream = fs.open(fstatus[i].getPath());
                    byte[] buffer = new byte[(int) size];
                    widgetStream.readFully(buffer);
                    widgetStream.close();
                    try {
                        WidgetBean widget = new WidgetBean(new JSONObject(new String(buffer)));
                        catalog.addCatalog(widget);
                        list.put(widget.getId(), widget);
                    } catch (Exception e) {
                        log.error(ExceptionUtil.getStackTrace(e));
                    }
                }
            }
        } catch (IOException ex) {
            log.error(ExceptionUtil.getStackTrace(ex));
            throw new IllegalAccessException("Unable to access user view database.");
        }
    }

    public static CatalogBean getCatalog() throws IllegalAccessException {
        if (catalog == null) {
            cacheWidgets();
        }
        return catalog;
    }

    public static HashMap<String, WidgetBean> list() throws IllegalAccessException {
        if (list.size() == 0) {
            cacheWidgets();
        }
        return list;
    }
}