com.thinkberg.moxo.dav.LockHandler.java Source code

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Here is the source code for com.thinkberg.moxo.dav.LockHandler.java

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/*
 * Copyright 2007 Matthias L. Jugel.
 *
 * 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.thinkberg.moxo.dav;

import com.thinkberg.moxo.dav.lock.Lock;
import com.thinkberg.moxo.dav.lock.LockConflictException;
import com.thinkberg.moxo.dav.lock.LockException;
import com.thinkberg.moxo.dav.lock.LockManager;
import org.apache.commons.vfs.FileObject;
import org.dom4j.Document;
import org.dom4j.DocumentException;
import org.dom4j.DocumentHelper;
import org.dom4j.Element;
import org.dom4j.Node;
import org.dom4j.io.SAXReader;
import org.dom4j.io.XMLWriter;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.net.URL;
import java.util.Iterator;

/**
 * Handle WebDAV LOCK requests.
 *
 * @author Matthias L. Jugel
 * @version $Id$
 */
public class LockHandler extends WebdavHandler {
    private static final String TAG_LOCKSCOPE = "lockscope";
    private static final String TAG_LOCKTYPE = "locktype";
    private static final String TAG_OWNER = "owner";
    private static final String TAG_HREF = "href";
    private static final String TAG_PROP = "prop";
    private static final String TAG_LOCKDISCOVERY = "lockdiscovery";

    private static final String HEADER_LOCK_TOKEN = "Lock-Token";

    public void service(HttpServletRequest request, HttpServletResponse response) throws IOException {
        FileObject object = getResourceManager().getFileObject(request.getPathInfo());

        try {
            Lock lock = LockManager.getInstance().checkCondition(object, getIf(request));
            if (lock != null) {
                sendLockAcquiredResponse(response, lock);
                return;
            }
        } catch (LockException e) {
            // handle locks below
        }

        try {
            SAXReader saxReader = new SAXReader();
            Document lockInfo = saxReader.read(request.getInputStream());
            //log(lockInfo);

            Element rootEl = lockInfo.getRootElement();
            String lockScope = null, lockType = null;
            Object owner = null;
            Iterator elIt = rootEl.elementIterator();
            while (elIt.hasNext()) {
                Element el = (Element) elIt.next();
                if (TAG_LOCKSCOPE.equals(el.getName())) {
                    lockScope = el.selectSingleNode("*").getName();
                } else if (TAG_LOCKTYPE.equals(el.getName())) {
                    lockType = el.selectSingleNode("*").getName();
                } else if (TAG_OWNER.equals(el.getName())) {
                    // TODO correctly handle owner
                    Node subEl = el.selectSingleNode("*");
                    if (subEl != null && TAG_HREF.equals(subEl.getName())) {
                        owner = new URL(el.selectSingleNode("*").getText());
                    } else {
                        owner = el.getText();
                    }
                }
            }

            log("LOCK(" + lockType + ", " + lockScope + ", " + owner + ")");

            Lock requestedLock = new Lock(object, lockType, lockScope, owner, getDepth(request),
                    getTimeout(request));
            try {
                LockManager.getInstance().acquireLock(requestedLock);
                sendLockAcquiredResponse(response, requestedLock);
            } catch (LockConflictException e) {
                response.sendError(SC_LOCKED);
            } catch (IllegalArgumentException e) {
                response.sendError(HttpServletResponse.SC_BAD_REQUEST);
            }
        } catch (DocumentException e) {
            e.printStackTrace();
            response.sendError(HttpServletResponse.SC_BAD_REQUEST);
        }
    }

    private void sendLockAcquiredResponse(HttpServletResponse response, Lock lock) throws IOException {
        response.setContentType("text/xml");
        response.setCharacterEncoding("UTF-8");
        response.setHeader(HEADER_LOCK_TOKEN, "<" + lock.getToken() + ">");

        Document propDoc = DocumentHelper.createDocument();
        Element propEl = propDoc.addElement(TAG_PROP, "DAV:");
        Element lockdiscoveryEl = propEl.addElement(TAG_LOCKDISCOVERY);

        lock.serializeToXml(lockdiscoveryEl);

        XMLWriter xmlWriter = new XMLWriter(response.getWriter());
        xmlWriter.write(propDoc);
        log(propDoc);
    }
}