mml.handler.get.MMLGetVersionsHandler.java Source code

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Here is the source code for mml.handler.get.MMLGetVersionsHandler.java

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/*
 * This file is part of MML.
 *
 *  MML is free software: you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation, either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  MML is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with MML.  If not, see <http://www.gnu.org/licenses/>.
 *  (c) copyright Desmond Schmidt 2014
 */

package mml.handler.get;

import calliope.core.constants.Database;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import mml.constants.Params;
import mml.exception.MMLException;
import mml.handler.AeseResource;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Set;
import org.json.simple.JSONObject;
import org.json.simple.JSONArray;

/**
 * Get the versions of the current docid
 * @author desmond
 */
public class MMLGetVersionsHandler extends MMLGetHandler {
    /**
     * Get the version listing from the MVD
     * @param request the request
     * @param response the response
     * @param urn the remaining urn being empty
     * @throws MMLException 
     */
    public void handle(HttpServletRequest request, HttpServletResponse response, String urn) throws MMLException {
        try {
            String docid = request.getParameter(Params.DOCID);
            if (docid == null)
                throw new Exception("You must specify a docid parameter");
            AeseResource res = doGetResource(Database.CORTEX, docid);
            JSONArray jVersions = new JSONArray();
            if (res != null) {
                String[] versions = res.listVersions();
                HashMap<String, JSONObject> vSet = new HashMap<String, JSONObject>();
                for (int i = 0; i < versions.length; i++) {
                    String base = Layers.stripLayer(versions[i]);
                    JSONObject jObj = vSet.get(base);
                    if (jObj == null)
                        jObj = new JSONObject();
                    String upgraded = Layers.upgradeLayerName(versions, versions[i]);
                    if (!upgraded.equals(versions[i])) {
                        JSONArray repl = (JSONArray) jObj.get("replacements");
                        if (repl == null) {
                            repl = new JSONArray();
                            jObj.put("replacements", repl);
                        }
                        JSONObject entry = new JSONObject();
                        entry.put("old", versions[i]);
                        entry.put("new", upgraded);
                        repl.add(entry);
                    }
                    if (upgraded.endsWith("layer-final"))
                        jObj.put("desc", res.getVersionLongName(i + 1));
                    // add the layer names
                    if (upgraded.endsWith("layer-final") || upgraded.matches(".*layer-[0-9]+$")) {
                        JSONArray jArr = (JSONArray) jObj.get("layers");
                        if (jArr == null)
                            jArr = new JSONArray();
                        int index = upgraded.lastIndexOf("layer");
                        String layerName = upgraded.substring(index);
                        if (!jArr.contains(layerName))
                            jArr.add(layerName);
                        if (!jObj.containsKey("layers"))
                            jObj.put("layers", jArr);
                    }
                    if (!vSet.containsKey(base))
                        vSet.put(base, jObj);
                }
                // convert hashmap to array
                Set<String> keys = vSet.keySet();
                Iterator<String> iter = keys.iterator();
                while (iter.hasNext()) {
                    String version = iter.next();
                    JSONObject jObj = vSet.get(version);
                    jObj.put("vid", version);
                    jVersions.add(jObj);
                }
            }
            response.setContentType("application/json");
            response.setCharacterEncoding(encoding);
            String jStr = jVersions.toJSONString().replaceAll("\\\\/", "/");
            response.getWriter().println(jStr);
        } catch (Exception e) {
            throw new MMLException(e);
        }
    }
}