SubscriberHandshake.java
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00001 /*
00002  * Copyright (C) 2011 Google Inc.
00003  * 
00004  * Licensed under the Apache License, Version 2.0 (the "License"); you may not
00005  * use this file except in compliance with the License. You may obtain a copy of
00006  * the License at
00007  * 
00008  * http://www.apache.org/licenses/LICENSE-2.0
00009  * 
00010  * Unless required by applicable law or agreed to in writing, software
00011  * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
00012  * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
00013  * License for the specific language governing permissions and limitations under
00014  * the License.
00015  */
00016 
00017 package org.ros.internal.node.topic;
00018 
00019 import com.google.common.base.Preconditions;
00020 
00021 import org.apache.commons.logging.Log;
00022 import org.apache.commons.logging.LogFactory;
00023 import org.ros.internal.node.BaseClientHandshake;
00024 import org.ros.internal.transport.ConnectionHeader;
00025 import org.ros.internal.transport.ConnectionHeaderFields;
00026 
00032 public class SubscriberHandshake extends BaseClientHandshake {
00033 
00034   private static final boolean DEBUG = false;
00035   private static final Log log = LogFactory.getLog(SubscriberHandshake.class);
00036 
00037   public SubscriberHandshake(ConnectionHeader outgoingConnectionHeader) {
00038     super(outgoingConnectionHeader);
00039     Preconditions.checkNotNull(outgoingConnectionHeader.getField(ConnectionHeaderFields.TYPE));
00040     Preconditions.checkNotNull(outgoingConnectionHeader
00041         .getField(ConnectionHeaderFields.MD5_CHECKSUM));
00042   }
00043 
00044   @Override
00045   public boolean handshake(ConnectionHeader incommingConnectionHeader) {
00046     if (DEBUG) {
00047       log.info("Outgoing subscriber connection header: " + outgoingConnectionHeader);
00048       log.info("Incoming publisher connection header: " + incommingConnectionHeader);
00049     }
00050     setErrorMessage(incommingConnectionHeader.getField(ConnectionHeaderFields.ERROR));
00051     String incomingType = incommingConnectionHeader.getField(ConnectionHeaderFields.TYPE);
00052     if (incomingType == null) {
00053       setErrorMessage("Incoming type cannot be null.");
00054     } else if (!incomingType.equals(outgoingConnectionHeader.getField(ConnectionHeaderFields.TYPE))) {
00055       setErrorMessage("Message types don't match.");
00056     }
00057     String incomingMd5Checksum =
00058         incommingConnectionHeader.getField(ConnectionHeaderFields.MD5_CHECKSUM);
00059     if (incomingMd5Checksum == null) {
00060       setErrorMessage("Incoming MD5 checksum cannot be null.");
00061     } else if (!incomingMd5Checksum.equals(outgoingConnectionHeader
00062         .getField(ConnectionHeaderFields.MD5_CHECKSUM))) {
00063       setErrorMessage("Checksums don't match.");
00064     }
00065     return getErrorMessage() == null;
00066   }
00067 }


rosjava_core
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autogenerated on Wed Aug 26 2015 16:06:49