Mercurial > jdk8-mips64-public > langtools / file revision

 /*

  * Copyright 1999-2008 Sun Microsystems, Inc.  All Rights Reserved.

  * 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

  * published by the Free Software Foundation.  Sun designates this

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

  * by Sun in the LICENSE file that accompanied this code.

  *

  * 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.

  *

  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,

  * CA 95054 USA or visit www.sun.com if you need additional information or

  * have any questions.

  */

 package com.sun.tools.javac.util;

 import java.io.*;

 /** A byte buffer is a flexible array which grows when elements are

  *  appended. There are also methods to append names to byte buffers

  *  and to convert byte buffers to names.

  *

  *  <p><b>This is NOT part of any API supported by Sun Microsystems.  If

  *  you write code that depends on this, you do so at your own risk.

  *  This code and its internal interfaces are subject to change or

  *  deletion without notice.</b>

  */

 public class ByteBuffer {

     /** An array holding the bytes in this buffer; can be grown.

      */

     public byte[] elems;

     /** The current number of defined bytes in this buffer.

      */

     public int length;

     /** Create a new byte buffer.

      */

     public ByteBuffer() {

         this(64);

     }

     /** Create a new byte buffer with an initial elements array

      *  of given size.

      */

     public ByteBuffer(int initialSize) {

         elems = new byte[initialSize];

         length = 0;

     }

     private void copy(int size) {

         byte[] newelems = new byte[size];

         System.arraycopy(elems, 0, newelems, 0, elems.length);

         elems = newelems;

     }

     /** Append byte to this buffer.

      */

     public void appendByte(int b) {

         if (length >= elems.length) copy(elems.length * 2);

         elems[length++] = (byte)b;

     }

     /** Append `len' bytes from byte array,

      *  starting at given `start' offset.

      */

     public void appendBytes(byte[] bs, int start, int len) {

         while (length + len > elems.length) copy(elems.length * 2);

         System.arraycopy(bs, start, elems, length, len);

         length += len;

     }

     /** Append all bytes from given byte array.

      */

     public void appendBytes(byte[] bs) {

         appendBytes(bs, 0, bs.length);

     }

     /** Append a character as a two byte number.

      */

     public void appendChar(int x) {

         while (length + 1 >= elems.length) copy(elems.length * 2);

         elems[length  ] = (byte)((x >>  8) & 0xFF);

         elems[length+1] = (byte)((x      ) & 0xFF);

         length = length + 2;

     }

     /** Append an integer as a four byte number.

      */

     public void appendInt(int x) {

         while (length + 3 >= elems.length) copy(elems.length * 2);

         elems[length  ] = (byte)((x >> 24) & 0xFF);

         elems[length+1] = (byte)((x >> 16) & 0xFF);

         elems[length+2] = (byte)((x >>  8) & 0xFF);

         elems[length+3] = (byte)((x      ) & 0xFF);

         length = length + 4;

     }

     /** Append a long as an eight byte number.

      */

     public void appendLong(long x) {

         ByteArrayOutputStream buffer = new ByteArrayOutputStream(8);

         DataOutputStream bufout = new DataOutputStream(buffer);

         try {

             bufout.writeLong(x);

             appendBytes(buffer.toByteArray(), 0, 8);

         } catch (IOException e) {

             throw new AssertionError("write");

         }

     }

     /** Append a float as a four byte number.

      */

     public void appendFloat(float x) {

         ByteArrayOutputStream buffer = new ByteArrayOutputStream(4);

         DataOutputStream bufout = new DataOutputStream(buffer);

         try {

             bufout.writeFloat(x);

             appendBytes(buffer.toByteArray(), 0, 4);

         } catch (IOException e) {

             throw new AssertionError("write");

         }

     }

     /** Append a double as a eight byte number.

      */

     public void appendDouble(double x) {

         ByteArrayOutputStream buffer = new ByteArrayOutputStream(8);

         DataOutputStream bufout = new DataOutputStream(buffer);

         try {

             bufout.writeDouble(x);

             appendBytes(buffer.toByteArray(), 0, 8);

         } catch (IOException e) {

             throw new AssertionError("write");

         }

     }

     /** Append a name.

      */

     public void appendName(Name name) {

         appendBytes(name.getByteArray(), name.getByteOffset(), name.getByteLength());

     }

     /** Reset to zero length.

      */

     public void reset() {

         length = 0;

     }

     /** Convert contents to name.

      */

     public Name toName(Names names) {

         return names.fromUtf(elems, 0, length);

     }

 }