1 /*
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3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4  *
5  * This code is free software; you can redistribute it and/or modify it
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7  * published by the Free Software Foundation.  Oracle designates this
8  * particular file as subject to the "Classpath" exception as provided
9  * by Oracle in the LICENSE file that accompanied this code.
10  *
11  * This code is distributed in the hope that it will be useful, but WITHOUT
12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14  * version 2 for more details (a copy is included in the LICENSE file that
15  * accompanied this code).
16  *
17  * You should have received a copy of the GNU General Public License version
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19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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24  */
25 
26 package com.sun.tools.sjavac.server;
27 
28 import com.sun.tools.javac.main.Main;
29 import com.sun.tools.sjavac.Log;
30 import com.sun.tools.sjavac.Util;
31 
32 import java.io.BufferedReader;
33 import java.io.InputStreamReader;
34 import java.io.PrintWriter;
35 import java.net.Socket;
36 import java.nio.file.Path;
37 
38 import static com.sun.tools.sjavac.server.SjavacServer.LINE_TYPE_RC;
39 
40 
41 /**
42  * A RequestHandler handles requests performed over a socket. Specifically it
43  *  - Reads the command string specifying which method is to be invoked
44  *  - Reads the appropriate arguments
45  *  - Delegates the actual invocation to the given sjavac implementation
46  *  - Writes the result back to the socket output stream
47  *
48  * None of the work performed by this class is really bound by the CPU. It
49  * should be completely fine to have a large number of RequestHandlers active.
50  * To limit the number of concurrent compilations, use PooledSjavac.
51  *
52  *  <p><b>This is NOT part of any supported API.
53  *  If you write code that depends on this, you do so at your own risk.
54  *  This code and its internal interfaces are subject to change or
55  *  deletion without notice.</b>
56  */
57 public class RequestHandler extends Thread {
58 
59     private final Socket socket;
60     private final Sjavac sjavac;
61 
RequestHandler(Socket socket, Sjavac sjavac)62     public RequestHandler(Socket socket, Sjavac sjavac) {
63         this.socket = socket;
64         this.sjavac = sjavac;
65     }
66 
67     @Override
run()68     public void run() {
69 
70         try (BufferedReader in = new BufferedReader(new InputStreamReader(socket.getInputStream()));
71              PrintWriter out = new PrintWriter(socket.getOutputStream(), true)) {
72 
73             // Set up logging for this thread. Stream back logging messages to
74             // client on the format format "level:msg".
75             Log.setLogForCurrentThread(new Log(out, out) {
76                 @Override
77                 protected boolean isLevelLogged(Level l) {
78                     // Make sure it is up to the client to decide whether or
79                     // not this message should be displayed.
80                     return true;
81                 }
82 
83                 @Override
84                 protected void printLogMsg(Level msgLevel, String msg) {
85                     // Follow sjavac server/client protocol: Send one line
86                     // at a time and prefix with message with "level:".
87                     Util.getLines(msg)
88                         .map(line -> msgLevel + ":" + line)
89                         .forEach(line -> super.printLogMsg(msgLevel, line));
90                 }
91             });
92 
93             // Read argument array
94             int n = Integer.parseInt(in.readLine());
95             String[] args = new String[n];
96             for (int i = 0; i < n; i++) {
97                 args[i] = in.readLine();
98             }
99 
100             // If there has been any internal errors, notify client
101             checkInternalErrorLog();
102 
103             // Perform compilation
104             Main.Result rc = sjavac.compile(args);
105 
106             // Send return code back to client
107             out.println(LINE_TYPE_RC + ":" + rc.name());
108 
109             // Check for internal errors again.
110             checkInternalErrorLog();
111         } catch (Exception ex) {
112             // Not much to be done at this point. The client side request
113             // code will most likely throw an IOException and the
114             // compilation will fail.
115             Log.error(ex);
116         } finally {
117             Log.setLogForCurrentThread(null);
118         }
119     }
120 
checkInternalErrorLog()121     private void checkInternalErrorLog() {
122         Path errorLog = ServerMain.getErrorLog().getLogDestination();
123         if (errorLog != null) {
124             Log.error("Server has encountered an internal error. See " + errorLog.toAbsolutePath()
125                     + " for details.");
126         }
127     }
128 }
129