jodd-servlet/src/main/java/jodd/servlet/wrapper/Buffer.java
public ServletOutputStream getOutputStream() {
		if (outStream == null) {
			if (outWriter != null) {
				throw new IllegalStateException("Can't call getOutputStream() after getWriter()");
			}
			bufferOutputStream = new FastByteArrayServletOutputStream();
			outStream = bufferOutputStream;
		}
		return outStream;
	}
public ServletOutputStream getOutputStream() {
		if (outStream == null) {
			if (outWriter != null) {
				throw new IllegalStateException("Can't call getOutputStream() after getWriter()");
			}
			bufferOutputStream = new FastByteArrayServletOutputStream();
			outStream = bufferOutputStream;
		}
		return outStream;
	}
Returns a servlet output stream.