dataoutputstream.java

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public final void
writeByte(int b) throws IOException
{
  out.write(b);

  ++written;
}

/*************************************************************************/

/**
  * This method writes all the bytes in a <code>String</code> out to the
  * stream.  One byte is written for each character in the <code>String</code>.
  * The high eight bits of each character are discarded.
  *
  * @param s The <code>String</code> to write to the stream
  *
  * @exception IOException If an error occurs
  */
public final void
writeBytes(String s) throws IOException
{
  if (s.length() == 0)
    return;

  byte[] buf = new byte[s.length()];

  for (int i = 0; i < s.length(); i++)
    buf[i] = (byte)(s.charAt(i) & 0xFF);

  out.write(buf);

  written += buf.length;
}

/*************************************************************************/

/**
  * This method writes a single <code>char</code> value to the stream,
  * high byte first.
  *
  * @param c The <code>char</code> value to write, passed as an <code>int</code>.
  *
  * @exception IOException If an error occurs
  */
public final void
writeChar(int c) throws IOException
{
  out.write(convertFromChar(c));

  written += 2;
}

/*************************************************************************/

/**
  * This method writes all the characters in a <code>String</code> to the
  * stream.  There will be two bytes for each character value.  The high
  * byte of the character will be written first.
  *
  * @param s The <code>String</code> to write to the stream.
  *
  * @exception IOException If an error occurs
  */
public final void
writeChars(String s) throws IOException
{
  if (s.length() == 0)
    return;

  byte[] buf = getConvertedStringChars(s);
  out.write(buf);

  written += buf.length;
}

/*************************************************************************/

/**
  * This method writes a Java <code>short</code> to the stream, high byte
  * first.  This method requires two bytes to encode the value.
  *
  * @param s The <code>short</code> value to write to the stream, passed as an <code>int</code>.
  *
  * @exception IOException If an error occurs
  */
public final void
writeShort(int s) throws IOException
{
  out.write(convertFromShort(s));

  written += 2;
}

/*************************************************************************/

/**
  * This method writes a Java <code>int</code> to the stream, high bytes
  * first.  This method requires four bytes to encode the value.
  *
  * @param i The <code>int</code> value to write to the stream.
  *
  * @exception IOException If an error occurs
  */
public final void
writeInt(int i) throws IOException
{
  out.write(convertFromInt(i));

  written += 4;
}

/*************************************************************************/

/**
  * This method writes a Java <code>long</code> to the stream, high bytes
  * first.  This method requires eight bytes to encode the value.
  *
  * @param l The <code>long</code> value to write to the stream.
  *
  * @exception IOException If an error occurs
  */
public final void
writeLong(long l) throws IOException
{
  out.write(convertFromLong(l));

  written += 8;
}

/*************************************************************************/

/**
  * This method writes a Java <code>float</code> value to the stream.  This
  * value is written by first calling the method <code>Float.floatToIntBits</code>
  * to retrieve an <code>int</code> representing the floating point number,
  * then writing this <code>int</code> value to the stream exactly the same
  * as the <code>writeInt()</code> method does.
  *
  * @param f The floating point number to write to the stream.
  *
  * @exception IOException If an error occurs
  *
  * @see writeInt
  */
public final void
writeFloat(float f) throws IOException
{
  int i = Float.floatToIntBits(f);
  writeInt(i);
}

/*************************************************************************/

/**
  * This method writes a Java <code>double</code> value to the stream.  This
  * value is written by first calling the method <code>Double.doubleToLongBits</code>
  * to retrieve an <code>long</code> representing the floating point number,
  * then writing this <code>long</code> value to the stream exactly the same
  * as the <code>writeLong()</code> method does.
  *
  * @param d The double precision floating point number to write to the stream.
  *
  * @exception IOException If an error occurs
  *
  * @see writeLong
  */
public final void
writeDouble(double d) throws IOException
{
  long l = Double.doubleToLongBits(d);
  writeLong(l);
}

/*************************************************************************/

/**
  * This method writes a Java <code>String</code> to the stream in a modified
  * UTF-8 format.  First, two bytes are written to the stream indicating the
  * number of bytes to follow.  Note that this is the number of bytes in the
  * encoded <code>String</code> not the <code>String</code> length.  Next
  * come the encoded characters.  Each character in the <code>String</code>
  * is encoded as either one, two or three bytes.  For characters in the
  * range of <code>\u0001</code> to <\u007F>, one byte is used.  The character
  * value goes into bits 0-7 and bit eight is 0.  For characters in the range
  * of <code>\u0080</code> to <code>\u007FF</code>, two bytes are used.  Bits
  * 6-10 of the character value are encoded bits 0-4 of the first byte, with
  * the high bytes having a value of "110".  Bits 0-5 of the character value
  * are stored in bits 0-5 of the second byte, with the high bits set to
  * "10".  This type of encoding is also done for the null character
  * <code>\u0000</code>.  This eliminates any C style NUL character values
  * in the output.  All remaining characters are stored as three bytes.
  * Bits 12-15 of the character value are stored in bits 0-3 of the first
  * byte.  The high bits of the first bytes are set to "1110".  Bits 6-11
  * of the character value are stored in bits 0-5 of the second byte.  The
  * high bits of the second byte are set to "10".  And bits 0-5 of the
  * character value are stored in bits 0-5 of byte three, with the high bits
  * of that byte set to "10".
  *
  * @param s The <code>String</code> to write to the output in UTF format
  *
  * @exception IOException If an error occurs
  */
public synchronized final void
writeUTF(String s) throws IOException
{
  byte[] buf = convertToUTF(s);

  writeShort(buf.length);
  out.write(buf);

  written += buf.length;
}

/*************************************************************************/

/**
  * This method writes the specified byte (passed as an <code>int</code>)
  * to the underlying output stream.
  *
  * @param b The byte to write, passed as an <code>int</code>.
  *
  * @exception IOException If an error occurs.
  */
public void
write(int b) throws IOException
{
  out.write(b);
  ++written;
}

/*************************************************************************/

/**
  * This method writes <code>len</code> bytes from the specified byte array
  * <code>buf</code> starting at position <code>offset</code> into the
  * buffer to the underlying output stream.
  *
  * @param buf The byte array to write from.
  * @param offset The index into the byte array to start writing from.
  * @param len The number of bytes to write.
  *
  * @exception IOException If an error occurs.
  */
public void
write(byte[] buf, int offset, int len) throws IOException
{
  out.write(buf, offset, len);
  written += len;
}

/*************************************************************************/

/**
  * This method flushes any unwritten bytes to the underlying stream.
  *
  * @exception IOException If an error occurs.
  */
public void
flush() throws IOException
{
  out.flush();
}

} // class DataOutputStream