1600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang/* 2600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang* Conditions Of Use 3600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang* 4600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang* This software was developed by employees of the National Institute of 5600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang* Standards and Technology (NIST), an agency of the Federal Government. 6600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang* Pursuant to title 15 Untied States Code Section 105, works of NIST 7600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang* employees are not subject to copyright protection in the United States 8600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang* and are considered to be in the public domain. As a result, a formal 9600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang* license is not needed to use the software. 10600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang* 11600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang* This software is provided by NIST as a service and is expressly 12600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang* provided "AS IS." NIST MAKES NO WARRANTY OF ANY KIND, EXPRESS, IMPLIED 13600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang* OR STATUTORY, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTY OF 14600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, NON-INFRINGEMENT 15600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang* AND DATA ACCURACY. NIST does not warrant or make any representations 16600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang* regarding the use of the software or the results thereof, including but 17600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang* not limited to the correctness, accuracy, reliability or usefulness of 18600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang* the software. 19600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang* 20600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang* Permission to use this software is contingent upon your acceptance 21600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang* of the terms of this agreement 22600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang* 23600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang* . 24600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang* 25600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang*/ 26600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang/******************************************************************************* 27600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang* Product of NIST/ITL Advanced Networking Technologies Division (ANTD). * 28600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang*******************************************************************************/ 29600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wangpackage gov.nist.javax.sip.header; 30600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wangimport javax.sip.header.*; 31600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wangimport javax.sip.InvalidArgumentException; 32600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang 33600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang/** 34600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang * MaxForwards SIPHeader 35600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang * 36600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang * @version 1.2 $Revision: 1.8 $ $Date: 2009/07/17 18:57:32 $ 37600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang * 38600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang * @author M. Ranganathan <br/> 39600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang * @author Olivier Deruelle <br/> 40600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang * 41600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang */ 42600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wangpublic class MaxForwards extends SIPHeader implements MaxForwardsHeader { 43600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang 44600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang /** 45600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang * Comment for <code>serialVersionUID</code> 46600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang */ 47600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang private static final long serialVersionUID = -3096874323347175943L; 48600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang /** maxForwards field. 49600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang */ 50600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang protected int maxForwards; 51600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang 52600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang /** Default constructor. 53600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang */ 54600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang public MaxForwards() { 55600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang super(NAME); 56600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang } 57600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang 58600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang public MaxForwards( int m ) throws InvalidArgumentException { 59600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang super(NAME); 60600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang this.setMaxForwards( m ); 61600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang } 62600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang 63600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang /** get the MaxForwards field. 64600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang * @return the maxForwards member. 65600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang */ 66600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang public int getMaxForwards() { 67600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang return maxForwards; 68600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang } 69600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang 70600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang /** 71600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang * Set the maxForwards member 72600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang * @param maxForwards maxForwards parameter to set 73600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang */ 74600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang public void setMaxForwards(int maxForwards) 75600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang throws InvalidArgumentException { 76600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang if (maxForwards < 0 || maxForwards > 255) 77600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang throw new InvalidArgumentException( 78600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang "bad max forwards value " + maxForwards); 79600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang this.maxForwards = maxForwards; 80600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang } 81600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang 82600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang /** 83600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang * Encode into a string. 84600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang * @return encoded string. 85600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang * 86600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang */ 87600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang public String encodeBody() { 88600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang return encodeBody(new StringBuffer()).toString(); 89600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang } 90600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang 91600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang protected StringBuffer encodeBody(StringBuffer buffer) { 92600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang return buffer.append(maxForwards); 93600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang } 94600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang 95600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang /** Boolean function 96600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang * @return true if MaxForwards field reached zero. 97600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang */ 98600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang public boolean hasReachedZero() { 99600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang return maxForwards == 0; 100600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang } 101600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang 102600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang /** decrement MaxForwards field one by one. 103600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang */ 104600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang public void decrementMaxForwards() throws TooManyHopsException { 105600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang if (maxForwards > 0) 106600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang maxForwards--; 107600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang else throw new TooManyHopsException ("has already reached 0!"); 108600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang } 109600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang 110600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang public boolean equals(Object other) { 111600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang if (this==other) return true; 112600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang if (other instanceof MaxForwardsHeader) { 113600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang final MaxForwardsHeader o = (MaxForwardsHeader) other; 114600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang return this.getMaxForwards() == o.getMaxForwards(); 115600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang } 116600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang return false; 117600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang } 118600c7a4bbc7348167293eac928192e695b4ad5baChung-yih Wang} 119