LoggingOutputStream.java

package org.springframework.roo.support.logging;

import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.util.logging.Level;
import java.util.logging.LogRecord;
import java.util.logging.Logger;

import org.apache.commons.io.IOUtils;
import org.apache.commons.lang3.Validate;

/**
 * Wraps an {@link OutputStream} and automatically passes each line to the
 * {@link Logger} when {@link OutputStream#flush()} or
 * {@link OutputStream#close()} is called.
 * 
 * @author Ben Alex
 * @since 1.1
 */
public class LoggingOutputStream extends OutputStream {

  protected static final Logger LOGGER = HandlerUtils.getLogger(LoggingOutputStream.class);

  private ByteArrayOutputStream baos = new ByteArrayOutputStream();
  private int count;
  private final Level level;
  private String sourceClassName = LoggingOutputStream.class.getName();

  /**
   * Constructor
   * 
   * @param level the level at which to log (required)
   */
  public LoggingOutputStream(final Level level) {
    Validate.notNull(level, "A logging level is required");
    this.level = level;
  }

  @Override
  public void close() throws IOException {
    flush();
  }

  @Override
  public void flush() throws IOException {
    if (count > 0) {
      final String msg = new String(baos.toByteArray());
      final LogRecord record = new LogRecord(level, msg);
      record.setSourceClassName(sourceClassName);
      try {
        LOGGER.log(record);
      } finally {
        count = 0;
        IOUtils.closeQuietly(baos);
        baos = new ByteArrayOutputStream();
      }
    }
  }

  public String getSourceClassName() {
    return sourceClassName;
  }

  public void setSourceClassName(final String sourceClassName) {
    this.sourceClassName = sourceClassName;
  }

  @Override
  public void write(final int b) throws IOException {
    baos.write(b);
    count++;
  }
}