001/*
002 * Copyright 2014 Atteo.
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 *      http://www.apache.org/licenses/LICENSE-2.0
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 */
016
017package org.atteo.moonshine.webjars;
018
019import java.io.DataInputStream;
020import java.io.IOException;
021import java.io.InputStream;
022
023import javax.servlet.ServletException;
024import javax.servlet.ServletOutputStream;
025import javax.servlet.http.HttpServlet;
026import javax.servlet.http.HttpServletRequest;
027import javax.servlet.http.HttpServletResponse;
028
029public class WebJarsServlet extends HttpServlet {
030    private static final int BUFSIZE = 4096;
031    private final String destination;
032
033    public WebJarsServlet(String destination) {
034        this.destination = destination;
035    }
036
037    @Override
038    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException,
039            IOException {
040        String path = request.getPathInfo();
041        if (path == null) {
042            response.sendError(HttpServletResponse.SC_NOT_FOUND);
043            return;
044        }
045
046        String mimetype = request.getServletContext().getMimeType(path);
047        if (mimetype == null) {
048            mimetype = "application/octet-stream";
049        }
050        response.setContentType(mimetype);
051
052        try (InputStream stream = WebJarsServlet.class.getResourceAsStream(destination + path);
053                DataInputStream dataStream = new DataInputStream(stream);
054                ServletOutputStream out = response.getOutputStream()) {
055            if (stream == null) {
056                response.sendError(HttpServletResponse.SC_NOT_FOUND);
057                return;
058            }
059
060            int length;
061            byte[] byteBuffer = new byte[BUFSIZE];
062            while ((length = dataStream.read(byteBuffer)) != -1) {
063                out.write(byteBuffer, 0, length);
064            }
065        }
066    }
067}