/** * @(#)ByteBuffer.java	1.13 03/01/23 * * Copyright 2003 Sun Microsystems, Inc. All rights reserved. * SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms. */package com.sun.tools.javac.v8.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. */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) {        super();        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) & 255);        elems[length + 1] = (byte)((x) & 255);        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) & 255);        elems[length + 1] = (byte)((x >> 16) & 255);        elems[length + 2] = (byte)((x >> 8) & 255);        elems[length + 3] = (byte)((x) & 255);        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.table.names, name.index, name.len);    }    /**      * Reset to zero length.      */    public void reset() {        length = 0;    }    /**      * Convert contents to name.      */    public Name toName(Name.Table names) {        return names.fromUtf(elems, 0, length);    }}