PipelineTest.java revision 15491:6f390eafc676 
1/*
2 * Copyright (c) 2015, Oracle and/or its affiliates. All rights reserved.
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
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 */
23
24import java.io.File;
25import java.io.FileReader;
26import java.io.FileWriter;
27import java.io.IOException;
28import java.io.InputStream;
29import java.io.OutputStream;
30import java.io.Reader;
31import java.io.Writer;
32import java.util.Arrays;
33import java.util.List;
34
35/*
36 * @test PipelineTest
37 */
38
39public class PipelineTest {
40
41    private static void realMain(String[] args) throws Throwable {
42        t1_simplePipeline();
43        t2_translatePipeline();
44        t3_redirectErrorStream();
45        t4_failStartPipeline();
46    }
47
48    /**
49     * Return a list of the varargs arguments.
50     * @param args elements to include in the list
51     * @param <T> the type of the elements
52     * @return a {@code List<T>} of the arguments
53     */
54    @SafeVarargs
55    @SuppressWarnings("varargs")
56    static <T> List<T> asList(T... args) {
57        return Arrays.asList(args);
58    }
59
60    /**
61     * T1 - simple copy between two processes
62     */
63    static void t1_simplePipeline() {
64        try {
65            String s1 = "Now is the time to check!";
66            verify(s1, s1,
67                    asList(new ProcessBuilder("cat")));
68            verify(s1, s1,
69                    asList(new ProcessBuilder("cat"),
70                            new ProcessBuilder("cat")));
71            verify(s1, s1,
72                    asList(new ProcessBuilder("cat"),
73                            new ProcessBuilder("cat"),
74                            new ProcessBuilder("cat")));
75        } catch (Throwable t) {
76            unexpected(t);
77        }
78    }
79
80    /**
81     * Pipeline that modifies the content.
82     */
83    static void t2_translatePipeline() {
84        try {
85            String s2 = "Now is the time to check!";
86            String r2 = s2.replace('e', 'E').replace('o', 'O');
87            verify(s2, r2,
88                    asList(new ProcessBuilder("tr", "e", "E"),
89                            new ProcessBuilder("tr", "o", "O")));
90        } catch (Throwable t) {
91            unexpected(t);
92        }
93    }
94
95    /**
96     * Test that redirectErrorStream sends standard error of the first process
97     * to the standard output. The standard error of the first process should be empty.
98     * The standard output of the 2nd should contain the error message including the bad file name.
99     */
100    static void t3_redirectErrorStream() {
101        try {
102            File p1err = new File("p1-test.err");
103            File p2out = new File("p2-test.out");
104
105            List<Process> processes = ProcessBuilder.startPipeline(
106                    asList(new ProcessBuilder("cat", "NON-EXISTENT-FILE")
107                                    .redirectErrorStream(true)
108                                    .redirectError(p1err),
109                            new ProcessBuilder("cat").redirectOutput(p2out)));
110            waitForAll(processes);
111
112            check("".equals(fileContents(p1err)), "The first process standard error should be empty");
113            String p2contents = fileContents(p2out);
114            check(p2contents.contains("NON-EXISTENT-FILE"),
115                    "The error from the first process should be in the output of the second: " + p2contents);
116        } catch (Throwable t) {
117            unexpected(t);
118        }
119    }
120
121    /**
122     * Test that no processes are left after a failed startPipeline.
123     * Test illegal combinations of redirects.
124     */
125    static void t4_failStartPipeline() {
126        File p1err = new File("p1-test.err");
127        File p2out = new File("p2-test.out");
128
129        THROWS(IllegalArgumentException.class,
130                () -> {
131                    // Test that output redirect != PIPE throws IAE
132                    List<Process> processes = ProcessBuilder.startPipeline(
133                            asList(new ProcessBuilder("cat", "NON-EXISTENT-FILE1")
134                                            .redirectOutput(p1err),
135                                    new ProcessBuilder("cat")));
136                },
137                () -> {
138                    // Test that input redirect != PIPE throws IAE
139                    List<Process> processes = ProcessBuilder.startPipeline(
140                            asList(new ProcessBuilder("cat", "NON-EXISTENT-FILE2"),
141                                    new ProcessBuilder("cat").redirectInput(p2out)));
142                }
143        );
144
145        THROWS(NullPointerException.class,
146                () -> {
147                    List<Process> processes = ProcessBuilder.startPipeline(
148                            asList(new ProcessBuilder("cat", "a"), null));
149                },
150                () -> {
151                    List<Process> processes = ProcessBuilder.startPipeline(
152                            asList(null, new ProcessBuilder("cat", "b")));
153                }
154        );
155
156        THROWS(IOException.class,
157                () -> {
158                    List<Process> processes = ProcessBuilder.startPipeline(
159                            asList(new ProcessBuilder("cat", "c"),
160                                    new ProcessBuilder("NON-EXISTENT-COMMAND")));
161                });
162
163        // Check no subprocess are left behind
164        ProcessHandle.current().children().forEach(PipelineTest::print);
165        ProcessHandle.current().children()
166                .filter(p -> p.info().command().orElse("").contains("cat"))
167                .forEach(p -> fail("process should have been destroyed: " + p));
168    }
169
170    static void verify(String input, String expected, List<ProcessBuilder> builders) throws IOException {
171        File infile = new File("test.in");
172        File outfile = new File("test.out");
173        setFileContents(infile, expected);
174        for (int i = 0; i < builders.size(); i++) {
175            ProcessBuilder b = builders.get(i);
176            if (i == 0) {
177                b.redirectInput(infile);
178            }
179            if (i == builders.size() - 1) {
180                b.redirectOutput(outfile);
181            }
182        }
183        List<Process> processes = ProcessBuilder.startPipeline(builders);
184        verifyProcesses(processes);
185        waitForAll(processes);
186        String result = fileContents(outfile);
187        System.out.printf(" in: %s%nout: %s%n", input, expected);
188        check(result.equals(expected), "result not as expected");
189    }
190
191    /**
192     * Wait for each of the processes to be done.
193     *
194     * @param processes the list  of processes to check
195     */
196    static void waitForAll(List<Process> processes) {
197        processes.forEach(p -> {
198            try {
199                int status = p.waitFor();
200            } catch (InterruptedException ie) {
201                unexpected(ie);
202            }
203        });
204    }
205
206    static void print(ProcessBuilder pb) {
207        if (pb != null) {
208            System.out.printf(" pb: %s%n", pb);
209            System.out.printf("    cmd: %s%n", pb.command());
210        }
211    }
212
213    static void print(ProcessHandle p) {
214        System.out.printf("process: pid: %d, info: %s%n",
215                p.getPid(), p.info());
216    }
217
218    // Check various aspects of the processes
219    static void verifyProcesses(List<Process> processes) {
220        for (int i = 0; i < processes.size(); i++) {
221            Process p = processes.get(i);
222            if (i != 0) {
223                verifyNullStream(p.getOutputStream(), "getOutputStream");
224            }
225            if (i == processes.size() - 1) {
226                verifyNullStream(p.getInputStream(), "getInputStream");
227                verifyNullStream(p.getErrorStream(), "getErrorStream");
228            }
229        }
230    }
231
232    static void verifyNullStream(OutputStream s, String msg) {
233        try {
234            s.write(0xff);
235            fail("Stream should have been a NullStream" + msg);
236        } catch (IOException ie) {
237            // expected
238        }
239    }
240
241    static void verifyNullStream(InputStream s, String msg) {
242        try {
243            int len = s.read();
244            check(len == -1, "Stream should have been a NullStream" + msg);
245        } catch (IOException ie) {
246            // expected
247        }
248    }
249
250    static void setFileContents(File file, String contents) {
251        try {
252            Writer w = new FileWriter(file);
253            w.write(contents);
254            w.close();
255        } catch (Throwable t) { unexpected(t); }
256    }
257
258    static String fileContents(File file) {
259        try {
260            Reader r = new FileReader(file);
261            StringBuilder sb = new StringBuilder();
262            char[] buffer = new char[1024];
263            int n;
264            while ((n = r.read(buffer)) != -1)
265                sb.append(buffer,0,n);
266            r.close();
267            return new String(sb);
268        } catch (Throwable t) { unexpected(t); return ""; }
269    }
270
271    //--------------------- Infrastructure ---------------------------
272    static volatile int passed = 0, failed = 0;
273    static void pass() {passed++;}
274    static void fail() {failed++; Thread.dumpStack();}
275    static void fail(String msg) {System.err.println(msg); fail();}
276    static void unexpected(Throwable t) {failed++; t.printStackTrace();}
277    static void check(boolean cond) {if (cond) pass(); else fail();}
278    static void check(boolean cond, String m) {if (cond) pass(); else fail(m);}
279    static void equal(Object x, Object y) {
280        if (x == null ? y == null : x.equals(y)) pass();
281        else fail(">'" + x + "'<" + " not equal to " + "'" + y + "'");
282    }
283
284    public static void main(String[] args) throws Throwable {
285        try {realMain(args);} catch (Throwable t) {unexpected(t);}
286        System.out.printf("%nPassed = %d, failed = %d%n%n", passed, failed);
287        if (failed > 0) throw new AssertionError("Some tests failed");
288    }
289    interface Fun {void f() throws Throwable;}
290    static void THROWS(Class<? extends Throwable> k, Fun... fs) {
291        for (Fun f : fs)
292            try { f.f(); fail("Expected " + k.getName() + " not thrown"); }
293            catch (Throwable t) {
294                if (k.isAssignableFrom(t.getClass())) pass();
295                else unexpected(t);}
296    }
297
298}
299