com.google.gwt.site.webapp.server.resources.HashServlet.java Source code

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Here is the source code for com.google.gwt.site.webapp.server.resources.HashServlet.java

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/*
 * Copyright 2013 Google Inc.
 *
 * 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 com.google.gwt.site.webapp.server.resources;

import java.io.IOException;
import java.util.List;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;

import com.google.appengine.api.datastore.DatastoreService;
import com.google.appengine.api.datastore.DatastoreServiceFactory;
import com.google.appengine.api.datastore.Entity;
import com.google.appengine.api.datastore.FetchOptions;
import com.google.appengine.api.datastore.PreparedQuery;
import com.google.appengine.api.datastore.Query;

public class HashServlet extends HttpServlet {

    private static final long serialVersionUID = -8648249883829261848L;

    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {

        int count;
        try {
            count = Integer.parseInt(req.getParameter("count"));
        } catch (NumberFormatException e) {
            throw new ServletException(e);
        }

        if (count < 0) {
            throw new ServletException("invalid value count " + count);
        }

        JSONObject root = new JSONObject();

        DatastoreService ds = DatastoreServiceFactory.getDatastoreService();

        PreparedQuery pq = ds.prepare(new Query("DocHash"));

        List<Entity> asList = pq.asList(FetchOptions.Builder.withOffset(count).limit(1000));
        JSONArray array = new JSONArray();

        try {
            root.put("hashes", array);
            for (Entity entity : asList) {
                count++;
                String key = entity.getKey().getName();
                String hash = (String) entity.getProperty("hash");

                JSONObject docHash = new JSONObject();
                docHash.put("key", key);
                docHash.put("hash", hash);
                array.put(docHash);
            }

            resp.getWriter().write(root.toString());
        } catch (JSONException e) {
            throw new ServletException(e);
        }
    }
}