mclub.util.loc.LocationCoderService.java Source code

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Here is the source code for mclub.util.loc.LocationCoderService.java

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/**
 * Project: MClubTracker
 * 
 * File Created at 2014-8-2
 * $id$
 * 
 * Copyright 2013, Shawn Chain (shawn.chain@gmail.com).
 * All rights reserved.
 *
 * Licensed 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 mclub.util.loc;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.InputStream;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;

import org.apache.commons.httpclient.HttpClient;
import org.apache.commons.httpclient.NameValuePair;
import org.apache.commons.httpclient.methods.GetMethod;
import org.apache.commons.io.IOUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.JSONObject;

/**
 * @author shawn
 * 
 */
public class LocationCoderService {
    private static final Logger log = LoggerFactory.getLogger(LocationCoderService.class);
    Map<String, LocationObject> addressLocationCache = new ConcurrentHashMap<String, LocationObject>();
    boolean dataUpdated;
    String localCacheFileName;

    public void start() {
        // startup the
    }

    public void stop() {

    }

    public LocationCoderService(String fileName) {
        this.localCacheFileName = fileName;
        loadCache();
    }

    public boolean isDataUpdated() {
        return dataUpdated;
    }

    public void loadCache() {
        InputStream is = null;
        try {
            // first load from local file system
            File f = new File(localCacheFileName);
            if (f.exists()) {
                is = new FileInputStream(f);
            } else {
                is = this.getClass().getResourceAsStream(localCacheFileName);
            }

            if (is != null) {
                String json = IOUtils.toString(is);
                // parse as json
                List<LocationObject> loc = JSON.parseArray(json, LocationObject.class);
                if (loc != null) {
                    for (LocationObject l : loc) {
                        addressLocationCache.put(l.addr, l);
                    }
                }
            }
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            IOUtils.closeQuietly(is);
        }
    }

    public void flushCache() {
        if (addressLocationCache == null || addressLocationCache.isEmpty()) {
            return;
        }
        FileOutputStream out = null;
        try {
            String jsonString = JSON.toJSONString(addressLocationCache.values());
            out = new FileOutputStream(localCacheFileName);
            IOUtils.write(jsonString, out);
            log.info("Locatio coder cache file" + localCacheFileName + " saved");
        } catch (Exception e) {
            log.warn("Error saving location coder cache file: " + e.getMessage());
        } finally {
            IOUtils.closeQuietly(out);
        }
    }

    /**
     * Get the location data of the address
     * @param addr
     * @return
     */
    public LocationObject getLocation(String addr) {
        return getLocation(addr, false);
    }

    public LocationObject getLocation(String addr, boolean onlineSearch) {
        LocationObject loc = addressLocationCache.get(addr);
        if (loc == null && onlineSearch) {
            loc = queryGeoCodeService(addr);
            if (loc != null) {
                addressLocationCache.put(loc.addr, loc);
                dataUpdated = true;
            }
        }
        return loc;
    }

    protected LocationObject queryGeoCodeService(String addr) {
        // - http://jueyue.iteye.com/blog/1688718
        // -
        // http://api.map.baidu.com/geocoder?address=%E6%B5%99%E6%B1%9F%E6%9D%AD%E5%B7%9E&output=json&key=g2fQ61PYZCgBwTY7YAk9c8n7&city=%E6%B5%99%E6%B1%9F%E6%9D%AD%E5%B7%9E
        LocationObject location = null;
        String apiURL = "http://api.map.baidu.com/geocoder";
        try {
            HttpClient client = new HttpClient();
            GetMethod httpget = new GetMethod(apiURL /* "http://api.map.baidu.com/geocoder" */);
            httpget.setRequestHeader("Accept-Charset", "utf-8,gb2312");

            List<NameValuePair> params = new ArrayList<NameValuePair>();
            params.add(new NameValuePair("address", addr));
            params.add(new NameValuePair("city", addr));
            params.add(new NameValuePair("output", "json"));
            params.add(new NameValuePair("key", "g2fQ61PYZCgBwTY7YAk9c8n7"));

            httpget.setQueryString(params.toArray(new NameValuePair[0]));

            int status = client.executeMethod(httpget);
            // System.out.println("Response status: " + status);
            log.debug("Response status: " + status);

            String jsonString = httpget.getResponseBodyAsString();
            log.debug("JSON:");
            log.debug(jsonString);
            // System.out.println("JSON:");
            // System.out.println(jsonString);

            JSONObject obj = (JSONObject) JSON.parse(jsonString);
            if (obj != null) {
                if ("OK".equalsIgnoreCase(obj.getString("status"))) {
                    JSONObject loc = obj.getJSONObject("result").getJSONObject("location");
                    if (loc != null) {
                        // construct the GeoLocation object
                        location = new LocationObject();
                        location.addr = addr;
                        location.lat = loc.getDouble("lat");
                        location.lon = loc.getDouble("lng");
                        //                  location.lat = String.format("%.6f",
                        //                        loc.getDouble("lat"));// new String(loc("lat");
                        //                  location.lon = String.format("%.6f",
                        //                        loc.getDouble("lng"));// loc.getString("lon");
                    }
                }

            }
        } catch (Exception e) {
            log.info("Error query location : " + e.getMessage());
        }

        return location;
    }
}