protected Writer() 
{
        this.lock = this;
}

Creates a new character-stream writer whose critical sections will synchronize on the writer itself.

 protected Writer(Object lock) 
{
        if (lock == null) {
            throw new NullPointerException();
        }
        this.lock = lock;
}

Creates a new character-stream writer whose critical sections will synchronize on the given object.

Parameters:

lock - Object to synchronize on

 public Writer append(CharSequence csq) throws IOException 
{
        if (csq == null)
            write("null");
        else
            write(csq.toString());
        return this;
}

Appends the specified character sequence to this writer.

An invocation of this method of the form out.append(csq) behaves in exactly the same way as the invocation

    out.write(csq.toString()) 

Depending on the specification of toString for the character sequence csq, the entire sequence may not be appended. For instance, invoking the toString method of a character buffer will return a subsequence whose content depends upon the buffer's position and limit.

 public Writer append(char c) throws IOException 
{
        write(c);
        return this;
}

Appends the specified character to this writer.

An invocation of this method of the form out.append(c) behaves in exactly the same way as the invocation

    out.write(c) 

 public Writer append(CharSequence csq,
    int start,
    int end) throws IOException 
{
        CharSequence cs = (csq == null ? "null" : csq);
        write(cs.subSequence(start, end).toString());
        return this;
}

Appends a subsequence of the specified character sequence to this writer. Appendable.

An invocation of this method of the form out.append(csq, start, end) when csq is not null behaves in exactly the same way as the invocation

    out.write(csq.subSequence(start, end).toString()) 

 abstract public  void close() throws IOException
Closes the stream, flushing it first. Once the stream has been closed,
further write() or flush() invocations will cause an IOException to be
thrown. Closing a previously closed stream has no effect.

 abstract public  void flush() throws IOException
Flushes the stream.  If the stream has saved any characters from the
various write() methods in a buffer, write them immediately to their
intended destination.  Then, if that destination is another character or
byte stream, flush it.  Thus one flush() invocation will flush all the
buffers in a chain of Writers and OutputStreams.

 If the intended destination of this stream is an abstraction provided
by the underlying operating system, for example a file, then flushing the
stream guarantees only that bytes previously written to the stream are
passed to the operating system for writing; it does not guarantee that
they are actually written to a physical device such as a disk drive.

 public  void write(int c) throws IOException 
{
        synchronized (lock) {
            if (writeBuffer == null){
                writeBuffer = new char[writeBufferSize];
            }
            writeBuffer[0] = (char) c;
            write(writeBuffer, 0, 1);
        }
}

Writes a single character. The character to be written is contained in the 16 low-order bits of the given integer value; the 16 high-order bits are ignored.

Subclasses that intend to support efficient single-character output should override this method.

 public  void write(char[] cbuf) throws IOException 
{
        write(cbuf, 0, cbuf.length);
}

Writes an array of characters.

 public  void write(String str) throws IOException 
{
        write(str, 0, str.length());
}

Writes a string.

 abstract public  void write(char[] cbuf,
    int off,
    int len) throws IOException
Writes a portion of an array of characters.

 public  void write(String str,
    int off,
    int len) throws IOException 
{
        synchronized (lock) {
            char cbuf[];
            if (len < = writeBufferSize) {
                if (writeBuffer == null) {
                    writeBuffer = new char[writeBufferSize];
                }
                cbuf = writeBuffer;
            } else {    // Don't permanently allocate very large buffers.
                cbuf = new char[len];
            }
            str.getChars(off, (off + len), cbuf, 0);
            write(cbuf, 0, len);
        }
}

Writes a portion of a string.