Log4J: How do I redirect an OutputStream or Writer to logger's writer(s)?

Question

I have a method which runs asynchronously after start, using OutputStream or Writer as parameter.

It acts as a recording adapter for an OutputStream or Writer (i

Answer 1

Building on Arthur Neves answer, I transferred this for Slf4J. I also improved this a bit using StringBuffer and directly casting byte to char:

import java.io.OutputStream;

import org.slf4j.Logger;

public class LogOutputStream extends OutputStream {
    private final Logger logger;

    /** The internal memory for the written bytes. */
    private StringBuffer mem;

    public LogOutputStream( final Logger logger ) {
        this.logger = logger;
        mem = new StringBuffer();
    }

    @Override
    public void write( final int b ) {
        if ( (char) b == '\n' ) {
            flush();
            return;
        }
        mem = mem.append( (char) b );
    }

    @Override
    public void flush() {
        logger.info( mem.toString() );
        mem = new StringBuffer();
    }
}