/* * Copyright (c) 1994, 2004, Oracle and/or its affiliates. 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.  Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */ package java.io; /** * A data output stream lets an application write primitive Java data * types to an output stream in a portable way. An application can * then use a data input stream to read the data back in. * * @author  unascribed * @see     java.io.DataInputStream * @since   JDK1.0 */publicclass DataOutputStream extends FilterOutputStream implements DataOutput {    /**     * The number of bytes written to the data output stream so far.     * If this counter overflows, it will be wrapped to Integer.MAX_VALUE.     */    protected int written;     /**     * bytearr is initialized on demand by writeUTF     */    private byte[] bytearr = null;     /**     * Creates a new data output stream to write data to the specified     * underlying output stream. The counter <code>written</code> is     * set to zero.     *     * @param   out   the underlying output stream, to be saved for later     *                use.     * @see     java.io.FilterOutputStream#out     */    public DataOutputStream(OutputStream out) {        super(out);    }     /**     * Increases the written counter by the specified value     * until it reaches Integer.MAX_VALUE.     */    private void incCount(int value) {        int temp = written + value;        if (temp < 0) {            temp = Integer.MAX_VALUE;        }        written = temp;    }     /**     * Writes the specified byte (the low eight bits of the argument     * <code>b</code>) to the underlying output stream. If no exception     * is thrown, the counter <code>written</code> is incremented by     * <code>1</code>.     * <p>     * Implements the <code>write</code> method of <code>OutputStream</code>.     *     * @param      b   the <code>byte</code> to be written.     * @exception  IOException  if an I/O error occurs.     * @see        java.io.FilterOutputStream#out     */    public synchronized void write(int b) throws IOException {        out.write(b);        incCount(1);    }     /**     * Writes <code>len</code> bytes from the specified byte array     * starting at offset <code>off</code> to the underlying output stream.     * If no exception is thrown, the counter <code>written</code> is     * incremented by <code>len</code>.     *     * @param      b     the data.     * @param      off   the start offset in the data.     * @param      len   the number of bytes to write.     * @exception  IOException  if an I/O error occurs.     * @see        java.io.FilterOutputStream#out     */    public synchronized void write(byte b[], int off, int len)        throws IOException    {        out.write(b, off, len);        incCount(len);    }     /**     * Flushes this data output stream. This forces any buffered output     * bytes to be written out to the stream.     * <p>     * The <code>flush</code> method of <code>DataOutputStream</code>     * calls the <code>flush</code> method of its underlying output stream.     *     * @exception  IOException  if an I/O error occurs.     * @see        java.io.FilterOutputStream#out     * @see        java.io.OutputStream#flush()     */    public void flush() throws IOException {        out.flush();    }     /**     * Writes a <code>boolean</code> to the underlying output stream as     * a 1-byte value. The value <code>true</code> is written out as the     * value <code>(byte)1</code>; the value <code>false</code> is     * written out as the value <code>(byte)0</code>. If no exception is     * thrown, the counter <code>written</code> is incremented by     * <code>1</code>.     *     * @param      v   a <code>boolean</code> value to be written.     * @exception  IOException  if an I/O error occurs.     * @see        java.io.FilterOutputStream#out     */    public final void writeBoolean(boolean v) throws IOException {        out.write(v ? 1 : 0);        incCount(1);    }     /**     * Writes out a <code>byte</code> to the underlying output stream as     * a 1-byte value. If no exception is thrown, the counter     * <code>written</code> is incremented by <code>1</code>.     *     * @param      v   a <code>byte</code> value to be written.     * @exception  IOException  if an I/O error occurs.     * @see        java.io.FilterOutputStream#out     */    public final void writeByte(int v) throws IOException {        out.write(v);        incCount(1);    }     /**     * Writes a <code>short</code> to the underlying output stream as two     * bytes, high byte first. If no exception is thrown, the counter     * <code>written</code> is incremented by <code>2</code>.     *     * @param      v   a <code>short</code> to be written.     * @exception  IOException  if an I/O error occurs.     * @see        java.io.FilterOutputStream#out     */    public final void writeShort(int v) throws IOException {        out.write((v >>> 8) & 0xFF);        out.write((v >>> 0) & 0xFF);        incCount(2);    }     /**     * Writes a <code>char</code> to the underlying output stream as a     * 2-byte value, high byte first. If no exception is thrown, the     * counter <code>written</code> is incremented by <code>2</code>.     *     * @param      v   a <code>char</code> value to be written.     * @exception  IOException  if an I/O error occurs.     * @see        java.io.FilterOutputStream#out     */    public final void writeChar(int v) throws IOException {        out.write((v >>> 8) & 0xFF);        out.write((v >>> 0) & 0xFF);        incCount(2);    }     /**     * Writes an <code>int</code> to the underlying output stream as four     * bytes, high byte first. If no exception is thrown, the counter     * <code>written</code> is incremented by <code>4</code>.     *     * @param      v   an <code>int</code> to be written.     * @exception  IOException  if an I/O error occurs.     * @see        java.io.FilterOutputStream#out     */    public final void writeInt(int v) throws IOException {        out.write((v >>> 24) & 0xFF);        out.write((v >>> 16) & 0xFF);        out.write((v >>>  8) & 0xFF);        out.write((v >>>  0) & 0xFF);        incCount(4);    }     private byte writeBuffer[] = new byte[8];     /**     * Writes a <code>long</code> to the underlying output stream as eight     * bytes, high byte first. In no exception is thrown, the counter     * <code>written</code> is incremented by <code>8</code>.     *     * @param      v   a <code>long</code> to be written.     * @exception  IOException  if an I/O error occurs.     * @see        java.io.FilterOutputStream#out     */    public final void writeLong(long v) throws IOException {        writeBuffer[0] = (byte)(v >>> 56);        writeBuffer[1] = (byte)(v >>> 48);        writeBuffer[2] = (byte)(v >>> 40);        writeBuffer[3] = (byte)(v >>> 32);        writeBuffer[4] = (byte)(v >>> 24);        writeBuffer[5] = (byte)(v >>> 16);        writeBuffer[6] = (byte)(v >>>  8);        writeBuffer[7] = (byte)(v >>>  0);        out.write(writeBuffer, 0, 8);        incCount(8);    }     /**     * Converts the float argument to an <code>int</code> using the     * <code>floatToIntBits</code> method in class <code>Float</code>,     * and then writes that <code>int</code> value to the underlying     * output stream as a 4-byte quantity, high byte first. If no     * exception is thrown, the counter <code>written</code> is     * incremented by <code>4</code>.     *     * @param      v   a <code>float</code> value to be written.     * @exception  IOException  if an I/O error occurs.     * @see        java.io.FilterOutputStream#out     * @see        java.lang.Float#floatToIntBits(float)     */    public final void writeFloat(float v) throws IOException {        writeInt(Float.floatToIntBits(v));    }     /**     * Converts the double argument to a <code>long</code> using the     * <code>doubleToLongBits</code> method in class <code>Double</code>,     * and then writes that <code>long</code> value to the underlying     * output stream as an 8-byte quantity, high byte first. If no     * exception is thrown, the counter <code>written</code> is     * incremented by <code>8</code>.     *     * @param      v   a <code>double</code> value to be written.     * @exception  IOException  if an I/O error occurs.     * @see        java.io.FilterOutputStream#out     * @see        java.lang.Double#doubleToLongBits(double)     */    public final void writeDouble(double v) throws IOException {        writeLong(Double.doubleToLongBits(v));    }     /**     * Writes out the string to the underlying output stream as a     * sequence of bytes. Each character in the string is written out, in     * sequence, by discarding its high eight bits. If no exception is     * thrown, the counter <code>written</code> is incremented by the     * length of <code>s</code>.     *     * @param      s   a string of bytes to be written.     * @exception  IOException  if an I/O error occurs.     * @see        java.io.FilterOutputStream#out     */    public final void writeBytes(String s) throws IOException {        int len = s.length();        for (int i = 0 ; i < len ; i++) {            out.write((byte)s.charAt(i));        }        incCount(len);    }     /**     * Writes a string to the underlying output stream as a sequence of     * characters. Each character is written to the data output stream as     * if by the <code>writeChar</code> method. If no exception is     * thrown, the counter <code>written</code> is incremented by twice     * the length of <code>s</code>.     *     * @param      s   a <code>String</code> value to be written.     * @exception  IOException  if an I/O error occurs.     * @see        java.io.DataOutputStream#writeChar(int)     * @see        java.io.FilterOutputStream#out     */    public final void writeChars(String s) throws IOException {        int len = s.length();        for (int i = 0 ; i < len ; i++) {            int v = s.charAt(i);            out.write((v >>> 8) & 0xFF);            out.write((v >>> 0) & 0xFF);        }        incCount(len * 2);    }     /**     * Writes a string to the underlying output stream using     * <a href="DataInput.html#modified-utf-8">modified UTF-8</a>     * encoding in a machine-independent manner.     * <p>     * First, two bytes are written to the output stream as if by the     * <code>writeShort</code> method giving the number of bytes to     * follow. This value is the number of bytes actually written out,     * not the length of the string. Following the length, each character     * of the string is output, in sequence, using the modified UTF-8 encoding     * for the character. If no exception is thrown, the counter     * <code>written</code> is incremented by the total number of     * bytes written to the output stream. This will be at least two     * plus the length of <code>str</code>, and at most two plus     * thrice the length of <code>str</code>.     *     * @param      str   a string to be written.     * @exception  IOException  if an I/O error occurs.     */    public final void writeUTF(String str) throws IOException {        writeUTF(str, this);    }     /**     * Writes a string to the specified DataOutput using     * <a href="DataInput.html#modified-utf-8">modified UTF-8</a>     * encoding in a machine-independent manner.     * <p>     * First, two bytes are written to out as if by the <code>writeShort</code>     * method giving the number of bytes to follow. This value is the number of     * bytes actually written out, not the length of the string. Following the     * length, each character of the string is output, in sequence, using the     * modified UTF-8 encoding for the character. If no exception is thrown, the     * counter <code>written</code> is incremented by the total number of     * bytes written to the output stream. This will be at least two     * plus the length of <code>str</code>, and at most two plus     * thrice the length of <code>str</code>.     *     * @param      str   a string to be written.     * @param      out   destination to write to     * @return     The number of bytes written out.     * @exception  IOException  if an I/O error occurs.     */    static int writeUTF(String str, DataOutput out) throws IOException {        int strlen = str.length();        int utflen = 0;        int c, count = 0;         /* use charAt instead of copying String to char array */        for (int i = 0; i < strlen; i++) {            c = str.charAt(i);            if ((c >= 0x0001) && (c <= 0x007F)) {                utflen++;            } else if (c > 0x07FF) {                utflen += 3;            } else {                utflen += 2;            }        }         if (utflen > 65535)            throw new UTFDataFormatException(                "encoded string too long: " + utflen + " bytes");         byte[] bytearr = null;        if (out instanceof DataOutputStream) {            DataOutputStream dos = (DataOutputStream)out;            if(dos.bytearr == null || (dos.bytearr.length < (utflen+2)))                dos.bytearr = new byte[(utflen*2) + 2];            bytearr = dos.bytearr;        } else {            bytearr = new byte[utflen+2];        }         bytearr[count++] = (byte) ((utflen >>> 8) & 0xFF);        bytearr[count++] = (byte) ((utflen >>> 0) & 0xFF);         int i=0;        for (i=0; i<strlen; i++) {           c = str.charAt(i);           if (!((c >= 0x0001) && (c <= 0x007F))) break;           bytearr[count++] = (byte) c;        }         for (;i < strlen; i++){            c = str.charAt(i);            if ((c >= 0x0001) && (c <= 0x007F)) {                bytearr[count++] = (byte) c;             } else if (c > 0x07FF) {                bytearr[count++] = (byte) (0xE0 | ((c >> 12) & 0x0F));                bytearr[count++] = (byte) (0x80 | ((c >>  6) & 0x3F));                bytearr[count++] = (byte) (0x80 | ((c >>  0) & 0x3F));            } else {                bytearr[count++] = (byte) (0xC0 | ((c >>  6) & 0x1F));                bytearr[count++] = (byte) (0x80 | ((c >>  0) & 0x3F));            }        }        out.write(bytearr, 0, utflen+2);        return utflen + 2;    }     /**     * Returns the current value of the counter <code>written</code>,     * the number of bytes written to this data output stream so far.     * If the counter overflows, it will be wrapped to Integer.MAX_VALUE.     *     * @return  the value of the <code>written</code> field.     * @see     java.io.DataOutputStream#written     */    public final int size() {        return written;    }}