1 /*
   2  * Copyright (c) 2000, 2004, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
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   7  * published by the Free Software Foundation.  Oracle designates this
   8  * particular file as subject to the "Classpath" exception as provided
   9  * by Oracle in the LICENSE file that accompanied this code.
  10  *
  11  * This code is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
  16  *
  17  * You should have received a copy of the GNU General Public License version
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  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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  25 package com.sun.corba.se.impl.encoding;
  26 
  27 import com.sun.corba.se.spi.ior.iiop.GIOPVersion;
  28 import com.sun.corba.se.impl.orbutil.ORBConstants;
  29 
  30 public class CDRInputStream_1_2 extends CDRInputStream_1_1
  31 {
  32     // Indicates whether the header is padded. In GIOP 1.2 and above,
  33     // the body must be aligned on an 8-octet boundary, and so the header is
  34     // padded appropriately. However, if there is no body to a request or reply
  35     // message, there is no header padding, in the unfragmented case.
  36     protected boolean headerPadding;
  37 
  38     // used to remember headerPadding flag when mark() and restore() are used.
  39     protected boolean restoreHeaderPadding;
  40 
  41     // Called by RequestMessage_1_2 or ReplyMessage_1_2 classes only.
  42     void setHeaderPadding(boolean headerPadding) {
  43         this.headerPadding = headerPadding;
  44     }
  45 
  46     // the mark and reset methods have been overridden to remember the
  47     // headerPadding flag.
  48 
  49     public void mark(int readlimit) {
  50         super.mark(readlimit);
  51         restoreHeaderPadding = headerPadding;
  52     }
  53 
  54     public void reset() {
  55         super.reset();
  56         headerPadding = restoreHeaderPadding;
  57         restoreHeaderPadding = false;
  58     }
  59 
  60     // Template method
  61     // This method has been overriden to ensure that the duplicated stream
  62     // inherits the headerPadding flag, in case of GIOP 1.2 and above, streams.
  63     public CDRInputStreamBase dup() {
  64         CDRInputStreamBase result = super.dup();
  65         ((CDRInputStream_1_2)result).headerPadding = this.headerPadding;
  66         return result;
  67     }
  68 
  69     protected void alignAndCheck(int align, int n) {
  70 
  71         // headerPadding bit is set by read method of the RequestMessage_1_2
  72         // or ReplyMessage_1_2 classes. When set, the very first body read
  73         // operation (from the stub code) would trigger an alignAndCheck
  74         // method call, that would in turn skip the header padding that was
  75         // inserted during the earlier write operation by the sender. The
  76         // padding ensures that the body is aligned on an 8-octet boundary,
  77         // for GIOP versions 1.2 and beyond.
  78         if (headerPadding == true) {
  79             headerPadding = false;
  80             alignOnBoundary(ORBConstants.GIOP_12_MSG_BODY_ALIGNMENT);
  81         }
  82 
  83         checkBlockLength(align, n);
  84 
  85         // WARNING: Must compute real alignment after calling
  86         // checkBlockLength since it may move the position
  87 
  88         // In GIOP 1.2, a fragment may end with some alignment
  89         // padding (which leads to all fragments ending perfectly
  90         // on evenly divisible 8 byte boundaries).  A new fragment
  91         // never requires alignment with the header since it ends
  92         // on an 8 byte boundary.
  93 
  94         int alignIncr = computeAlignment(bbwi.position(),align);
  95         bbwi.position(bbwi.position() + alignIncr);
  96 
  97         if (bbwi.position() + n > bbwi.buflen) {
  98             grow(1, n);
  99         }
 100     }
 101 
 102     public GIOPVersion getGIOPVersion() {
 103         return GIOPVersion.V1_2;
 104     }
 105 
 106     public char read_wchar() {
 107         // In GIOP 1.2, a wchar is encoded as an unsigned octet length
 108         // followed by the octets of the converted wchar.
 109         int numBytes = read_octet();
 110 
 111         char[] result = getConvertedChars(numBytes, getWCharConverter());
 112 
 113         // Did the provided bytes convert to more than one
 114         // character?  This may come up as more unicode values are
 115         // assigned, and a single 16 bit Java char isn't enough.
 116         // Better to use strings for i18n purposes.
 117         if (getWCharConverter().getNumChars() > 1)
 118             throw wrapper.btcResultMoreThanOneChar() ;
 119 
 120         return result[0];
 121     }
 122 
 123     public String read_wstring() {
 124         // In GIOP 1.2, wstrings are not terminated by a null.  The
 125         // length is the number of octets in the converted format.
 126         // A zero length string is represented with the 4 byte length
 127         // value of 0.
 128 
 129         int len = read_long();
 130 
 131         //
 132         // IMPORTANT: Do not replace 'new String("")' with "", it may result
 133         // in a Serialization bug (See serialization.zerolengthstring) and
 134         // bug id: 4728756 for details
 135         if (len == 0)
 136             return new String("");
 137 
 138         checkForNegativeLength(len);
 139 
 140         return new String(getConvertedChars(len, getWCharConverter()),
 141                           0,
 142                           getWCharConverter().getNumChars());
 143     }
 144 }