/*

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * particular file as subject to the "Classpath" exception as provided

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 */

package com.sun.corba.se.impl.encoding;

import com.sun.corba.se.spi.ior.iiop.GIOPVersion;

import com.sun.corba.se.impl.orbutil.ORBConstants;

public class CDRInputStream_1_2 extends CDRInputStream_1_1

{

    // Indicates whether the header is padded. In GIOP 1.2 and above,

    // the body must be aligned on an 8-octet boundary, and so the header is

    // padded appropriately. However, if there is no body to a request or reply

    // message, there is no header padding, in the unfragmented case.

    protected boolean headerPadding;

    // used to remember headerPadding flag when mark() and restore() are used.

    protected boolean restoreHeaderPadding;

    // Called by RequestMessage_1_2 or ReplyMessage_1_2 classes only.

    void setHeaderPadding(boolean headerPadding) {

        this.headerPadding = headerPadding;

    }

    // the mark and reset methods have been overridden to remember the

    // headerPadding flag.

    public void mark(int readlimit) {

        super.mark(readlimit);

        restoreHeaderPadding = headerPadding;

    }

    public void reset() {

        super.reset();

        headerPadding = restoreHeaderPadding;

        restoreHeaderPadding = false;

    }

    // Template method

    // This method has been overriden to ensure that the duplicated stream

    // inherits the headerPadding flag, in case of GIOP 1.2 and above, streams.

    public CDRInputStreamBase dup() {

        CDRInputStreamBase result = super.dup();

        ((CDRInputStream_1_2)result).headerPadding = this.headerPadding;

        return result;

    }

    protected void alignAndCheck(int align, int n) {

        // headerPadding bit is set by read method of the RequestMessage_1_2

        // or ReplyMessage_1_2 classes. When set, the very first body read

        // operation (from the stub code) would trigger an alignAndCheck

        // method call, that would in turn skip the header padding that was

        // inserted during the earlier write operation by the sender. The

        // padding ensures that the body is aligned on an 8-octet boundary,

        // for GIOP versions 1.2 and beyond.

        if (headerPadding == true) {

            headerPadding = false;

            alignOnBoundary(ORBConstants.GIOP_12_MSG_BODY_ALIGNMENT);

        }

        checkBlockLength(align, n);

        // WARNING: Must compute real alignment after calling

        // checkBlockLength since it may move the position

        // In GIOP 1.2, a fragment may end with some alignment

        // padding (which leads to all fragments ending perfectly

        // on evenly divisible 8 byte boundaries).  A new fragment

        // never requires alignment with the header since it ends

        // on an 8 byte boundary.

        int alignIncr = computeAlignment(bbwi.position(),align);

        bbwi.position(bbwi.position() + alignIncr);

        if (bbwi.position() + n > bbwi.buflen) {

            grow(1, n);

        }

    }

    public GIOPVersion getGIOPVersion() {

        return GIOPVersion.V1_2;

    }

    public char read_wchar() {

        // In GIOP 1.2, a wchar is encoded as an unsigned octet length

        // followed by the octets of the converted wchar.

        int numBytes = read_octet();

        char[] result = getConvertedChars(numBytes, getWCharConverter());

        // Did the provided bytes convert to more than one

        // character?  This may come up as more unicode values are

        // assigned, and a single 16 bit Java char isn't enough.

        // Better to use strings for i18n purposes.

        if (getWCharConverter().getNumChars() > 1)

            throw wrapper.btcResultMoreThanOneChar() ;

        return result[0];

    }

    public String read_wstring() {

        // In GIOP 1.2, wstrings are not terminated by a null.  The

        // length is the number of octets in the converted format.

        // A zero length string is represented with the 4 byte length

        // value of 0.

        int len = read_long();

        //

        // IMPORTANT: Do not replace 'new String("")' with "", it may result

        // in a Serialization bug (See serialization.zerolengthstring) and

        // bug id: 4728756 for details

        if (len == 0)

            return new String("");

        checkForNegativeLength(len);

        return new String(getConvertedChars(len, getWCharConverter()),

                          0,

                          getWCharConverter().getNumChars());

    }

}