com.sun.faces.application.ByteArrayWebOutputStream Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of jakarta.faces Show documentation
EE4J Compatible Implementation for Jakarta Faces API
The newest version!
/*
 * Copyright (c) 1997, 2020 Oracle and/or its affiliates. All rights reserved.
 *
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Public License v. 2.0, which is available at
 * http://www.eclipse.org/legal/epl-2.0.
 *
 * This Source Code may also be made available under the following Secondary
 * Licenses when the conditions for such availability set forth in the
 * Eclipse Public License v. 2.0 are satisfied: GNU General Public License,
 * version 2 with the GNU Classpath Exception, which is available at
 * https://www.gnu.org/software/classpath/license.html.
 *
 * SPDX-License-Identifier: EPL-2.0 OR GPL-2.0 WITH Classpath-exception-2.0
 */

package com.sun.faces.application;

import static java.util.logging.Level.FINE;

import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.io.Writer;
import java.nio.ByteBuffer;
import java.nio.CharBuffer;
import java.nio.charset.Charset;
import java.nio.charset.CharsetDecoder;
import java.util.logging.Logger;

import com.sun.faces.util.FacesLogger;

import jakarta.faces.FacesException;
import jakarta.servlet.ServletOutputStream;
import jakarta.servlet.WriteListener;

/**
 * This steam converts byte content to character. This implementation allows us to query whether or not the writer has
 * been flushed or closed. This is necessary to better mimic the actual Servlet response.
 */
class ByteArrayWebOutputStream extends ServletOutputStream {

    public static final ServletOutputStream NOOP_STREAM = new NoOpOutputStream();

    // Log instance for this class
    private static final Logger LOGGER = FacesLogger.APPLICATION.getLogger();

    private final DirectByteArrayOutputStream baos;
    private boolean committed;

    public ByteArrayWebOutputStream() {
        baos = new DirectByteArrayOutputStream(1024);
    }

    @Override
    public void write(int n) {
        baos.write(n);
    }

    /**
     * 
     * It's important to not expose this as reset.
     * 
     */

    public void resetByteArray() {
        baos.reset();
    }

    public byte[] toByteArray() {
        return baos.toByteArray();
    }

    /**
     * Converts the buffered bytes into chars based on the specified encoding and writes them to the provided Writer.
     *
     * @param writer target Writer
     * @param encoding character encoding
     */
    public void writeTo(Writer writer, String encoding) {
        if (LOGGER.isLoggable(FINE)) {
            LOGGER.fine("Converting buffered ServletOutputStream bytes" + " to chars using " + encoding);
        }

        ByteBuffer byteBuffer = baos.getByteBuffer();
        CharsetDecoder decoder = Charset.forName(encoding).newDecoder();

        try {
            CharBuffer charBuffer = decoder.decode(byteBuffer);
            writer.write(charBuffer.array());
        } catch (IOException ioe) {
            throw new FacesException(ioe);
        }
    }

    public boolean isCommitted() {
        return committed;
    }

    @Override
    public void close() throws IOException {
        committed = true;
    }

    @Override
    public void flush() throws IOException {
        committed = true;
    }

    /**
     * 
     * Write the buffered bytes to the provided OutputStream.
     * 
     *
     * @param stream the stream to write to
     */
    public void writeTo(OutputStream stream) {
        try {
            stream.write(baos.getByteBuffer().array());
        } catch (IOException ioe) {
            throw new FacesException(ioe);
        }
    }

    @Override
    public boolean isReady() {
        throw new UnsupportedOperationException("Not supported");
    }

    @Override
    public void setWriteListener(WriteListener wl) {
        throw new UnsupportedOperationException("Not supported");
    }

    private static class DirectByteArrayOutputStream extends ByteArrayOutputStream {

        // -------------------------------------------------------- Constructors

        public DirectByteArrayOutputStream(int initialCapacity) {
            super(initialCapacity);
        }

        // ------------------------------------------------------- PublicMethods

        /**
         * Return the buffer backing this ByteArrayOutputStream as a ByteBuffer.
         *
         * @return buf wrapped in a ByteBuffer
         */
        public ByteBuffer getByteBuffer() {
            return ByteBuffer.wrap(buf, 0, count);
        }

    }

    private static class NoOpOutputStream extends ServletOutputStream {

        @Override
        public void write(int b) throws IOException {
            // no-op
        }

        @Override
        public void write(byte b[]) throws IOException {
            // no-op
        }

        @Override
        public void write(byte b[], int off, int len) throws IOException {
            // no-op
        }

        @Override
        public void flush() throws IOException {
            // no-op
        }

        @Override
        public void close() throws IOException {
            // no-op
        }

        protected NoOpOutputStream() {
            // no-op
        }

        @Override
        public void print(String s) throws IOException {
            // no-op
        }

        @Override
        public void print(boolean b) throws IOException {
            // no-op
        }

        @Override
        public void print(char c) throws IOException {
            // no-op
        }

        @Override
        public void print(int i) throws IOException {
            // no-op
        }

        @Override
        public void print(long l) throws IOException {
            // no-op
        }

        @Override
        public void print(float v) throws IOException {
            // no-op
        }

        @Override
        public void print(double v) throws IOException {
            // no-op
        }

        @Override
        public void println() throws IOException {
            // no-op
        }

        @Override
        public void println(String s) throws IOException {
            // no-op
        }

        @Override
        public void println(boolean b) throws IOException {
            // no-op
        }

        @Override
        public void println(char c) throws IOException {
            // no-op
        }

        @Override
        public void println(int i) throws IOException {
            // no-op
        }

        @Override
        public void println(long l) throws IOException {
            // no-op
        }

        @Override
        public void println(float v) throws IOException {
            // no-op
        }

        @Override
        public void println(double v) throws IOException {
            // no-op
        }

        @Override
        public boolean isReady() {
            throw new UnsupportedOperationException("Not supported");
        }

        @Override
        public void setWriteListener(WriteListener wl) {
            throw new UnsupportedOperationException("Not supported");
        }
    }
}