written 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
- * b) to the underlying output stream. If no exception
- * is thrown, the counter written is incremented by
- * 1.
- *
- * Implements the write method of OutputStream.
- *
- * @param b the byte 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 len bytes from the specified byte array
- * starting at offset off to the underlying output stream.
- * If no exception is thrown, the counter written is
- * incremented by len.
- *
- * @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.
- *
- * The flush method of DataOutputStream
- * calls the flush 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 boolean to the underlying output stream as
- * a 1-byte value. The value true is written out as the
- * value (byte)1; the value false is
- * written out as the value (byte)0. If no exception is
- * thrown, the counter written is incremented by
- * 1.
- *
- * @param v a boolean 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 byte to the underlying output stream as
- * a 1-byte value. If no exception is thrown, the counter
- * written is incremented by 1.
- *
- * @param v a byte 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 short to the underlying output stream as two
- * bytes, high byte first. If no exception is thrown, the counter
- * written is incremented by 2.
- *
- * @param v a short 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 char to the underlying output stream as a
- * 2-byte value, high byte first. If no exception is thrown, the
- * counter written is incremented by 2.
- *
- * @param v a char 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 int to the underlying output stream as four
- * bytes, high byte first. If no exception is thrown, the counter
- * written is incremented by 4.
- *
- * @param v an int 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 long to the underlying output stream as eight
- * bytes, high byte first. In no exception is thrown, the counter
- * written is incremented by 8.
- *
- * @param v a long 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 int using the
- * floatToIntBits method in class Float,
- * and then writes that int value to the underlying
- * output stream as a 4-byte quantity, high byte first. If no
- * exception is thrown, the counter written is
- * incremented by 4.
- *
- * @param v a float 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 long using the
- * doubleToLongBits method in class Double,
- * and then writes that long value to the underlying
- * output stream as an 8-byte quantity, high byte first. If no
- * exception is thrown, the counter written is
- * incremented by 8.
- *
- * @param v a double 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 written is incremented by the
- * length of s.
- *
- * @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 writeChar method. If no exception is
- * thrown, the counter written is incremented by twice
- * the length of s.
- *
- * @param s a String 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
- * modified UTF-8
- * encoding in a machine-independent manner.
- *
- * First, two bytes are written to the output stream as if by the
- * writeShort 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
- * written is incremented by the total number of
- * bytes written to the output stream. This will be at least two
- * plus the length of str, and at most two plus
- * thrice the length of str.
- *
- * @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
- * modified UTF-8
- * encoding in a machine-independent manner.
- *
- * First, two bytes are written to out as if by the writeShort
- * 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 written is incremented by the total number of
- * bytes written to the output stream. This will be at least two
- * plus the length of str, and at most two plus
- * thrice the length of str.
- *
- * @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; iwritten,
- * 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 written field.
- * @see java.io.DataOutputStream#written
- */
- public final int size() {
- return written;
- }
-}