src/com/owncloud/android/operations/ExistenceCheckOperation.java

   1 /* ownCloud Android client application
   2  *   Copyright (C) 2012 ownCloud Inc.
   3  *
   4  *   This program is free software: you can redistribute it and/or modify
   5  *   it under the terms of the GNU General Public License version 2,
   6  *   as published by the Free Software Foundation.
   7  *
   8  *   This program is distributed in the hope that it will be useful,
   9  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  *   GNU General Public License for more details.
  12  *
  13  *   You should have received a copy of the GNU General Public License
  14  *   along with this program.  If not, see <http://www.gnu.org/licenses/>.
  15  *
  16  */
  17
  18 package com.owncloud.android.operations;
  19
  20 import org.apache.commons.httpclient.HttpStatus;
  21 import org.apache.commons.httpclient.methods.HeadMethod;
  22
  23 import com.owncloud.android.Log_OC;
  24 import com.owncloud.android.oc_framework.network.webdav.WebdavClient;
  25 import com.owncloud.android.oc_framework.operations.RemoteOperation;
  26 import com.owncloud.android.oc_framework.operations.RemoteOperationResult;
  27 import com.owncloud.android.oc_framework.network.webdav.WebdavUtils;
  28
  29 import android.content.Context;
  30 import android.net.ConnectivityManager;
  31
  32 /**
  33  * Operation to check the existence or absence of a path in a remote server.
  34  *
  35  * @author David A. Velasco
  36  */
  37 public class ExistenceCheckOperation extends RemoteOperation {
  38
  39     /** Maximum time to wait for a response from the server in MILLISECONDs.  */
  40     public static final int TIMEOUT = 10000;
  41
  42     private static final String TAG = ExistenceCheckOperation.class.getSimpleName();
  43
  44     private String mPath;
  45     private Context mContext;
  46     private boolean mSuccessIfAbsent;
  47
  48
  49     /**
  50      * Full constructor. Success of the operation will depend upon the value of successIfAbsent.
  51      *
  52      * @param path              Path to append to the URL owned by the client instance.
  53      * @param context           Android application context.
  54      * @param successIfAbsent   When 'true', the operation finishes in success if the path does NOT exist in the remote server (HTTP 404).
  55      */
  56     public ExistenceCheckOperation(String path, Context context, boolean successIfAbsent) {
  57         mPath = (path != null) ? path : "";
  58         mContext = context;
  59         mSuccessIfAbsent = successIfAbsent;
  60     }
  61
  62
  63         @Override
  64         protected RemoteOperationResult run(WebdavClient client) {
  65         if (!isOnline()) {
  66             return new RemoteOperationResult(RemoteOperationResult.ResultCode.NO_NETWORK_CONNECTION);
  67         }
  68         RemoteOperationResult result = null;
  69         HeadMethod head = null;
  70         try {
  71             head = new HeadMethod(client.getBaseUri() + WebdavUtils.encodePath(mPath));
  72             int status = client.executeMethod(head, TIMEOUT, TIMEOUT);
  73             client.exhaustResponse(head.getResponseBodyAsStream());
  74             boolean success = (status == HttpStatus.SC_OK && !mSuccessIfAbsent) || (status == HttpStatus.SC_NOT_FOUND && mSuccessIfAbsent);
  75             result = new RemoteOperationResult(success, status, head.getResponseHeaders());
  76             Log_OC.d(TAG, "Existence check for " + client.getBaseUri() + WebdavUtils.encodePath(mPath) + " targeting for " + (mSuccessIfAbsent ? " absence " : " existence ") + "finished with HTTP status " + status + (!success?"(FAIL)":""));
  77
  78         } catch (Exception e) {
  79             result = new RemoteOperationResult(e);
  80             Log_OC.e(TAG, "Existence check for " + client.getBaseUri() + WebdavUtils.encodePath(mPath) + " targeting for " + (mSuccessIfAbsent ? " absence " : " existence ") + ": " + result.getLogMessage(), result.getException());
  81
  82         } finally {
  83             if (head != null)
  84                 head.releaseConnection();
  85         }
  86         return result;
  87         }
  88
  89     private boolean isOnline() {
  90         ConnectivityManager cm = (ConnectivityManager) mContext
  91                 .getSystemService(Context.CONNECTIVITY_SERVICE);
  92         return cm != null && cm.getActiveNetworkInfo() != null
  93                 && cm.getActiveNetworkInfo().isConnectedOrConnecting();
  94     }
  95
  96
  97 }