- /*
- * @(#)DataOutputStream.java 1.43 04/05/13
- *
- * Copyright 2004 Sun Microsystems, Inc. All rights reserved.
- * SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
- */
-
- 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
- * @version 1.43, 05/13/04
- * @see java.io.DataInputStream
- * @since JDK1.0
- */
- public
- class 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;
- }
- }