1/*
2 * Copyright (c) 2004, 2011, Oracle and/or its affiliates. All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 *
8 *   - Redistributions of source code must retain the above copyright
9 *     notice, this list of conditions and the following disclaimer.
10 *
11 *   - Redistributions in binary form must reproduce the above copyright
12 *     notice, this list of conditions and the following disclaimer in the
13 *     documentation and/or other materials provided with the distribution.
14 *
15 *   - Neither the name of Oracle nor the names of its
16 *     contributors may be used to endorse or promote products derived
17 *     from this software without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
20 * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
21 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR
23 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
24 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
25 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
26 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
27 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
28 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
29 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
30 */
31
32/*
33 * This source code is provided to illustrate the usage of a given feature
34 * or technique and has been deliberately simplified. Additional steps
35 * required for a production-quality application, such as security checks,
36 * input validation and proper error handling, might not be present in
37 * this sample code.
38 */
39
40
41import java.io.*;
42import java.nio.*;
43import java.nio.channels.*;
44
45/**
46 * Primary driver class used by non-blocking Servers to receive,
47 * prepare, send, and shutdown requests.
48 *
49 * @author Mark Reinhold
50 * @author Brad R. Wetmore
51 */
52class RequestHandler implements Handler {
53
54    private ChannelIO cio;
55    private ByteBuffer rbb = null;
56
57    private boolean requestReceived = false;
58    private Request request = null;
59    private Reply reply = null;
60
61    private static int created = 0;
62
63    RequestHandler(ChannelIO cio) {
64        this.cio = cio;
65
66        // Simple heartbeat to let user know we're alive.
67        synchronized (RequestHandler.class) {
68            created++;
69            if ((created % 50) == 0) {
70                System.out.println(".");
71                created = 0;
72            } else {
73                System.out.print(".");
74            }
75        }
76    }
77
78    // Returns true when request is complete
79    // May expand rbb if more room required
80    //
81    private boolean receive(SelectionKey sk) throws IOException {
82        ByteBuffer tmp = null;
83
84        if (requestReceived) {
85            return true;
86        }
87
88        if (!cio.doHandshake(sk)) {
89            return false;
90        }
91
92        if ((cio.read() < 0) || Request.isComplete(cio.getReadBuf())) {
93            rbb = cio.getReadBuf();
94            return (requestReceived = true);
95        }
96        return false;
97    }
98
99    // When parse is successfull, saves request and returns true
100    //
101    private boolean parse() throws IOException {
102        try {
103            request = Request.parse(rbb);
104            return true;
105        } catch (MalformedRequestException x) {
106            reply = new Reply(Reply.Code.BAD_REQUEST,
107                              new StringContent(x));
108        }
109        return false;
110    }
111
112    // Ensures that reply field is non-null
113    //
114    private void build() throws IOException {
115        Request.Action action = request.action();
116        if ((action != Request.Action.GET) &&
117                (action != Request.Action.HEAD)) {
118            reply = new Reply(Reply.Code.METHOD_NOT_ALLOWED,
119                              new StringContent(request.toString()));
120        }
121        reply = new Reply(Reply.Code.OK,
122                          new FileContent(request.uri()), action);
123    }
124
125    public void handle(SelectionKey sk) throws IOException {
126        try {
127
128            if (request == null) {
129                if (!receive(sk))
130                    return;
131                rbb.flip();
132                if (parse())
133                    build();
134                try {
135                    reply.prepare();
136                } catch (IOException x) {
137                    reply.release();
138                    reply = new Reply(Reply.Code.NOT_FOUND,
139                                      new StringContent(x));
140                    reply.prepare();
141                }
142                if (send()) {
143                    // More bytes remain to be written
144                    sk.interestOps(SelectionKey.OP_WRITE);
145                } else {
146                    // Reply completely written; we're done
147                    if (cio.shutdown()) {
148                        cio.close();
149                        reply.release();
150                    }
151                }
152            } else {
153                if (!send()) {  // Should be rp.send()
154                    if (cio.shutdown()) {
155                        cio.close();
156                        reply.release();
157                    }
158                }
159            }
160        } catch (IOException x) {
161            String m = x.getMessage();
162            if (!m.equals("Broken pipe") &&
163                    !m.equals("Connection reset by peer")) {
164                System.err.println("RequestHandler: " + x.toString());
165            }
166
167            try {
168                /*
169                 * We had a failure here, so we'll try to be nice
170                 * before closing down and send off a close_notify,
171                 * but if we can't get the message off with one try,
172                 * we'll just shutdown.
173                 */
174                cio.shutdown();
175            } catch (IOException e) {
176                // ignore
177            }
178
179            cio.close();
180            if (reply !=  null) {
181                reply.release();
182            }
183        }
184
185    }
186
187    private boolean send() throws IOException {
188        try {
189            return reply.send(cio);
190        } catch (IOException x) {
191            if (x.getMessage().startsWith("Resource temporarily")) {
192                System.err.println("## RTA");
193                return true;
194            }
195            throw x;
196        }
197    }
198}
199