package class5_3_StreamDecorator_inClass;

import java.io.IOException;
import java.io.OutputStream;
import java.io.Writer;

/**
 * Adapter for a Writer to behave like an OutputStream.
 *
 * An Adapter is something like a Decorator, except the wrapping class does not implement the same interface
 * as the class that is wrapped.
 *
 * Bytes are converted to chars using the platform default encoding.
 * If this encoding is not a single-byte encoding, some data may be lost.
 *
 * Courtesy of http://www.coderanch.com/t/278540/java-io/java/create-PrintStream-PrintWriter
 *
 * I needed this to replace System.out with a wrapped version of System.out
 * (Not sure if there is any reason you would want to do this...
 * feels rather like a hack!)
 */
public class WriterOutputStream extends OutputStream {

    private final Writer writer;

    public WriterOutputStream(Writer writer) {
        this.writer = writer;
    }

    public void write(int b) throws IOException {
        // Jim Yingst from coderanch:
        // It's tempting to use writer.write((char) b), but that may get the encoding wrong
        // This is inefficient, but it works
        write(new byte[] {(byte) b}, 0, 1);
    }

    public void write(byte b[], int off, int len) throws IOException {
        writer.write(new String(b, off, len));
    }

    public void flush() throws IOException {
        writer.flush();
    }

    public void close() throws IOException {
        writer.close();
    }
}