Example usage for java.lang Process getErrorStream

List of usage examples for java.lang Process getErrorStream

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Introduction

In this page you can find the example usage for java.lang Process getErrorStream.

Prototype

public abstract InputStream getErrorStream();

Source Link

Document

Returns the input stream connected to the error output of the process.

Usage

From source file:com.twosigma.beaker.r.rest.RShellRest.java

private RServer startRserve() throws IOException, RserveException, REXPMismatchException {
    int port = getPortFromCore();
    String pluginInstallDir = System.getProperty("user.dir");
    String password = RandomStringUtils.random(40, true, true);
    String[] command = { "Rscript", writeRserveScript(port, password) };

    // Need to clear out some environment variables in order for a
    // new Java process to work correctly.
    // XXX not always necessary, use getPluginEnvps from BeakerConfig?
    // or just delete?
    List<String> environmentList = new ArrayList<>();
    for (Entry<String, String> entry : System.getenv().entrySet()) {
        if (!("CLASSPATH".equals(entry.getKey()))) {
            environmentList.add(entry.getKey() + "=" + entry.getValue());
        }//from   www. j a v  a  2  s  .c  o  m
    }
    String[] environmentArray = new String[environmentList.size()];
    environmentList.toArray(environmentArray);

    Process rServe = Runtime.getRuntime().exec(command, environmentArray);
    BufferedReader rServeOutput = new BufferedReader(new InputStreamReader(rServe.getInputStream(), "ASCII"));
    String line = null;
    while ((line = rServeOutput.readLine()) != null) {
        if (line.indexOf("(This session will block until Rserve is shut down)") >= 0) {
            break;
        } else {
            // System.out.println("Rserve>" + line);
        }
    }
    ErrorGobbler errorGobbler = new ErrorGobbler(rServe.getErrorStream());
    errorGobbler.start();

    ROutputHandler handler = new ROutputHandler(rServe.getInputStream(), BEGIN_MAGIC, END_MAGIC);
    handler.start();

    RConnection rconn = new RConnection("127.0.0.1", port);
    rconn.login("beaker", password);
    int pid = rconn.eval("Sys.getpid()").asInteger();
    return new RServer(rconn, handler, errorGobbler, port, password, pid);
}

From source file:de.flyingsnail.ipv6droid.android.VpnThread.java

/**
 *     Android 4.4 has introduced a bug with VPN routing. The android developers appear very
 *     pleased with their broken idea and unwilling to fix in any forseeable future.
 *     This methods tries to check if our device suffers from this problem.
 *     @return true if routing is OK//from   w w  w . j a  v a  2s . c om
 */
private boolean checkRouting() {
    try {
        Process routeChecker = Runtime.getRuntime()
                .exec(new String[] { "/system/bin/ip", "-f", "inet6", "route", "show", "default", "::/1" });
        BufferedReader reader = new BufferedReader(new InputStreamReader(routeChecker.getInputStream()));
        BufferedReader errreader = new BufferedReader(new InputStreamReader(routeChecker.getErrorStream()));
        String output = reader.readLine();
        String errors = errreader.readLine();
        try {
            routeChecker.waitFor();
        } catch (InterruptedException e) {
            // we got interrupted, so we kill our process
            routeChecker.destroy();
        }
        int exitValue = 0;
        try {
            exitValue = routeChecker.exitValue();
        } catch (IllegalStateException ise) {
            // command still running. Hmmm.
        }
        if (output == null || exitValue != 0) {
            Log.e(TAG, "error checking route: " + errors);
            return false; // default route is not set on ipv6
        } else
            return true;
    } catch (IOException e) {
        return false; // we cannot even check :-(
    }
}

From source file:com.photon.phresco.framework.commons.QualityUtil.java

public ArrayList<String> getConnAndroidDevices(String command) throws Exception {
    S_LOGGER.debug("Entering Method QualityUtil.getConnAndroidDevices() for quality tab");
    ArrayList<String> output = new ArrayList<String>();
    try {//from  w w  w . j a v  a 2s . c  om
        String s = null;
        Process p = Runtime.getRuntime().exec(command);

        BufferedReader stdInput = new BufferedReader(new InputStreamReader(p.getInputStream()));
        BufferedReader stdError = new BufferedReader(new InputStreamReader(p.getErrorStream()));

        int cnt = 0;
        while ((s = stdInput.readLine()) != null) {
            if (cnt > 0) {
                s = s.substring(0, s.indexOf("\t") + 1);
                output.add(s.trim());
            }
            cnt++;
        }
        stdInput.close();
        cnt = 0;
        while ((s = stdError.readLine()) != null) {
            if (cnt > 0) {
                s = s.substring(0, s.indexOf("\t") + 1);
                output.add(s.trim());
            }
            cnt++;
        }
        stdError.close();
    } catch (Exception e) {
        S_LOGGER.error("Entered into catch block of Quality.getConnAndroidDevices()"
                + FrameworkUtil.getStackTraceAsString(e));
    }
    output.remove(output.size() - 1);
    return output;
}

From source file:fr.ens.biologie.genomique.eoulsan.it.ITCommandExecutor.java

/**
 * Execute a script from a command line retrieved from the test configuration.
 * @param scriptConfKey key for configuration to get command line
 * @param suffixNameOutputFile suffix for standard and error output file on
 *          process//  w  w w.  j  av  a 2 s. co  m
 * @param desc description on command line
 * @param isApplicationCmdLine true if application to run, otherwise false
 *          corresponding to annexes script
 * @return result of execution command line, if command line not found in
 *         configuration return null
 */
public ITCommandResult executeCommand(final String scriptConfKey, final String suffixNameOutputFile,
        final String desc, final boolean isApplicationCmdLine) {

    if (this.testConf.getProperty(scriptConfKey) == null) {
        return null;
    }

    // Get command line from the configuration
    final String cmdLine = this.testConf.getProperty(scriptConfKey);

    if (cmdLine.isEmpty()) {
        return null;
    }

    // Save command line in file
    if (isApplicationCmdLine) {

        try {

            com.google.common.io.Files.write(cmdLine + "\n", this.cmdLineFile, Charsets.UTF_8);

        } catch (final IOException e) {

            getLogger().warning("Error while writing the application command line in file: " + e.getMessage());
        }
    }

    // Define stdout and stderr file
    final File stdoutFile = createSdtoutFile(suffixNameOutputFile);
    final File stderrFile = createSdterrFile(suffixNameOutputFile);

    int exitValue = -1;
    final Stopwatch timer = Stopwatch.createStarted();

    final ITCommandResult cmdResult = new ITCommandResult(cmdLine, this.outputTestDirectory, desc, durationMax);

    try {

        final Process p = Runtime.getRuntime().exec(cmdLine, this.environmentVariables,
                this.outputTestDirectory);

        // Init monitor and start
        final MonitorThread monitor = new MonitorThread(p, desc, durationMax);

        // Save stdout
        if (stdoutFile != null) {
            new CopyProcessOutput(p.getInputStream(), stdoutFile, "stdout").start();
        }

        // Save stderr
        if (stderrFile != null) {
            new CopyProcessOutput(p.getErrorStream(), stderrFile, "stderr").start();
        }

        // Wait the end of the process
        exitValue = p.waitFor();

        // Stop monitor thread
        monitor.interrupt();

        cmdResult.setExitValue(exitValue);

        // Execution script fail, create an exception
        if (exitValue != 0) {

            if (monitor.isKilledProcess()) {

                cmdResult.asInterruptedProcess();
                cmdResult.setException(
                        new EoulsanException("\tKill process.\n\tCommand line: " + cmdLine + "\n\tDirectory: "
                                + this.outputTestDirectory + "\n\tMessage: " + monitor.getMessage()));

            } else {

                cmdResult.setException(new EoulsanException("\tCommand line: " + cmdLine + "\n\tDirectory: "
                        + this.outputTestDirectory + "\n\tMessage: bad exit value: " + exitValue));
                cmdResult.setErrorFileOnProcess(stderrFile);
            }

        } else if (exitValue == 0 && !isApplicationCmdLine) {
            // Success execution, remove standard and error output file
            if (!stdoutFile.delete()) {
                getLogger().warning("Unable to deleted stdout file: " + stdoutFile);
            }
            if (!stderrFile.delete()) {
                getLogger().warning("Unable to deleted stderr file: " + stdoutFile);
            }
        }

    } catch (IOException | InterruptedException e) {
        cmdResult.setException(e, "\tError before execution.\n\tCommand line: " + cmdLine + "\n\tDirectory: "
                + this.outputTestDirectory + "\n\tMessage: " + e.getMessage());

    } finally {
        cmdResult.setDuration(timer.elapsed(TimeUnit.MILLISECONDS));
        timer.stop();
    }

    return cmdResult;
}

From source file:ixa.pipe.ned_ukb.Annotate.java

public void disambiguateNEsToKAF(KAFDocument kaf, String scripts, String ukbExec, String ukbKb, String ukbDict,
        String wikiDb) throws Exception {

    String resourceExternalRef = ukbKb.substring(ukbKb.lastIndexOf("/") + 1);

    List<String> neIds = new ArrayList<String>();
    String ukbContext = "naf\n";

    List<Entity> entities = kaf.getEntities();
    for (Entity entity : entities) {
        String entityId = entity.getId();
        String entityLemma = "";
        List<Term> entityTerms = entity.getTerms();
        for (Term term : entityTerms) {
            String tId = term.getId();
            neIds.add(tId);/*from  w ww . j  a  va2  s .  c  om*/
            if (!entityLemma.equals("")) {
                entityLemma += "_";
            }
            entityLemma += term.getLemma().toLowerCase();
        }
        ukbContext += entityLemma + "##" + entityId + "#1 ";
    }

    String formsContext2Match = "";
    String lemmasContext2Match = "";

    List<Term> terms = kaf.getTerms();
    for (Term term : terms) {
        if (!neIds.contains(term.getId())) {
            if (!(term.getForm().contains("@@")) && !(term.getForm().contains(" "))) {
                formsContext2Match += term.getForm().toLowerCase() + "@@" + term.getWFs().get(0).getOffset()
                        + " ";
                lemmasContext2Match += term.getLemma().toLowerCase() + "@@" + term.getWFs().get(0).getOffset()
                        + " ";
            }
        }
    }

    // create UKB context
    String[] cmdMatch = { "perl", scripts + "/merge_match.pl", "-d", wikiDb, "--t1", formsContext2Match, "--t2",
            lemmasContext2Match };

    Process pMatch = Runtime.getRuntime().exec(cmdMatch);

    String matchedContext = "";
    String outputLineContext = "";
    BufferedReader outputContextStream = new BufferedReader(
            new InputStreamReader(pMatch.getInputStream(), "UTF-8"));
    while ((outputLineContext = outputContextStream.readLine()) != null) {
        matchedContext += outputLineContext + "\n";
    }
    outputContextStream.close();

    String errorContext = "";
    BufferedReader errorContextStream = new BufferedReader(new InputStreamReader(pMatch.getErrorStream()));
    while ((errorContext = errorContextStream.readLine()) != null) {
        System.err.println("MERGE_MATCH ERROR: " + errorContext);
    }
    errorContextStream.close();

    pMatch.waitFor();

    String[] contextStrings = matchedContext.split(" ");
    for (String contextString : contextStrings) {
        if (contextString.equals(""))
            continue;
        contextString = contextString.trim();

        //ContextString = spot_string@@spot_offset
        String[] contextWordOffset = contextString.split("@@");
        ukbContext += contextWordOffset[0] + "##" + contextWordOffset[1] + "#1 ";
    }

    File contextTmpFile = File.createTempFile("context", ".tmp");
    contextTmpFile.deleteOnExit();
    String contextTmpFileName = contextTmpFile.getAbsolutePath();

    Writer contextFile = new BufferedWriter(
            new OutputStreamWriter(new FileOutputStream(contextTmpFile), "UTF-8"));
    try {
        contextFile.write(ukbContext);
    } finally {
        contextFile.close();
    }

    // run UKB
    String cmdUkb = ukbExec
            + " --prank_damping 0.90 --prank_iter 15 --allranks --minput --nopos --ppr_w2w --dict_weight -K "
            + ukbKb + " -D " + ukbDict + " " + contextTmpFileName;

    Process pUkb = Runtime.getRuntime().exec(cmdUkb);

    String outputUkb = "";
    String outputLineUkb = "";
    BufferedReader outputUkbStream = new BufferedReader(new InputStreamReader(pUkb.getInputStream(), "UTF-8"));
    while ((outputLineUkb = outputUkbStream.readLine()) != null) {
        outputUkb += outputLineUkb + "\n";
    }
    outputUkbStream.close();

    String errorUkb = "";
    BufferedReader errorUkbStream = new BufferedReader(new InputStreamReader(pUkb.getErrorStream()));
    while ((errorUkb = errorUkbStream.readLine()) != null) {
        System.err.println("UKB ERROR: " + errorUkb);
    }
    errorUkbStream.close();

    pUkb.waitFor();

    // UKB output (one line): context_id word_id (concept_id(/weight)?)+ !! lemma   (there are 2 spaces after word_id)
    // UKB output example:    naf e12  Norvegia/0.999998 Norvegiako_bandera/2.25207e-06 !! norvegia
    Map<String, String> entityLinks = new HashMap<String, String>(); // e12 --> Norvegia/0.999998
    String ukbDisambiguations[] = outputUkb.split("\n");
    for (String ukbDisambiguation : ukbDisambiguations) {
        if (ukbDisambiguation.startsWith("!! -v"))
            continue;
        String ukbLine[] = ukbDisambiguation.split(" ");
        entityLinks.put(ukbLine[1], ukbLine[3]);
    }

    // UKB links to KAF
    for (Entity entity : entities) {
        String entityId = entity.getId();
        if (entityLinks.containsKey(entityId)) {
            String reference = entityLinks.get(entityId).split("/")[0];
            String confidence = entityLinks.get(entityId).split("/")[1];
            String ref2 = reference;
            reference = "http://" + language + ".wikipedia.org/wiki/" + reference;
            ExternalRef externalRef = kaf.newExternalRef(resourceExternalRef, reference);
            externalRef.setConfidence(Float.parseFloat(confidence));
            externalRef.setSource(language);
            externalRef.setReftype(language);
            entity.addExternalRef(externalRef);
            if (cross) {
                String mappingRef = getMappingRef(reference);
                if (mappingRef != null) {
                    ExternalRef enRef = kaf.newExternalRef(this.resourceMapping, mappingRef);
                    enRef.setConfidence(Float.parseFloat(confidence));
                    enRef.setSource(language);
                    enRef.setReftype("en");
                    entity.addExternalRef(enRef);
                }
            }
        } else { // UKB didn't assign any link to this entity. Try with MFS
            String cmdMfs = "perl " + scripts + "/mfs.pl -d " + wikiDb;
            Process pMfs = Runtime.getRuntime().exec(cmdMfs);

            String entityLemma = "";
            List<Term> entityTerms = entity.getTerms();
            for (Term term : entityTerms) {
                if (!entityLemma.equals("")) {
                    entityLemma += "_";
                }
                entityLemma += term.getLemma().toLowerCase();
            }

            OutputStream stdinMfs = pMfs.getOutputStream();
            stdinMfs.write(entityLemma.getBytes());
            stdinMfs.flush();
            stdinMfs.close();

            String outputMfs = "";
            BufferedReader outputMfsStream = new BufferedReader(
                    new InputStreamReader(pMfs.getInputStream(), "UTF-8"));
            outputMfs = outputMfsStream.readLine();
            outputMfsStream.close();

            String errorMfs = "";
            BufferedReader errorMfsStream = new BufferedReader(new InputStreamReader(pMfs.getErrorStream()));
            while ((errorMfs = errorMfsStream.readLine()) != null) {
                System.err.println("MFS ERROR: " + errorMfs);
            }
            errorMfsStream.close();

            pMfs.waitFor();
            if (!outputMfs.equals("NILL")) {
                String reference = outputMfs;
                String confidence = "1";
                reference = "http://" + language + ".wikipedia.org/wiki/" + reference;
                ExternalRef externalRef = kaf.newExternalRef("MFS_" + resourceExternalRef, reference);
                externalRef.setConfidence(Float.parseFloat(confidence));
                externalRef.setSource(language);
                externalRef.setReftype(language);
                entity.addExternalRef(externalRef);
                if (cross) {
                    String mappingRef = getMappingRef(reference);
                    if (mappingRef != null) {
                        ExternalRef enRef = kaf.newExternalRef(this.resourceMapping, mappingRef);
                        enRef.setConfidence(Float.parseFloat(confidence));
                        enRef.setSource(language);
                        enRef.setReftype("en");
                        entity.addExternalRef(enRef);
                    }
                }

            }
        }
    }

}

From source file:metadata.etl.dataset.hdfs.HdfsMetadataEtl.java

private void extractLocal() throws Exception {

    URL localJarUrl = classLoader.getResource("jar/schemaFetch.jar");
    String homeDir = System.getProperty("user.home");
    String remoteJarFile = homeDir + "/.wherehows/schemaFetch.jar";
    File dest = new File(remoteJarFile);
    try {//from  ww w  . ja va  2  s  .co  m
        FileUtils.copyURLToFile(localJarUrl, dest);
    } catch (Exception e) {
        logger.error(e.toString());
    }

    String outputSchemaFile = prop.getProperty(Constant.HDFS_SCHEMA_LOCAL_PATH_KEY);
    String outputSampleDataFile = prop.getProperty(Constant.HDFS_SAMPLE_LOCAL_PATH_KEY);
    String cluster = prop.getProperty(Constant.HDFS_CLUSTER_KEY);
    String whiteList = prop.getProperty(Constant.HDFS_WHITE_LIST_KEY);
    String numOfThread = prop.getProperty(Constant.HDFS_NUM_OF_THREAD_KEY, String.valueOf(1));
    String hdfsUser = prop.getProperty(Constant.HDFS_REMOTE_USER_KEY);
    // String hdfsKeyTab = prop.getProperty(Constant.HDFS_REMOTE_KEYTAB_LOCATION_KEY);
    String hdfsExtractLogFile = outputSchemaFile + ".log";

    String[] hadoopCmd = { "hadoop", "jar", remoteJarFile,
            "-D" + Constant.HDFS_SCHEMA_REMOTE_PATH_KEY + "=" + outputSchemaFile,
            "-D" + Constant.HDFS_SAMPLE_REMOTE_PATH_KEY + "=" + outputSampleDataFile,
            "-D" + Constant.HDFS_CLUSTER_KEY + "=" + cluster,
            "-D" + Constant.HDFS_WHITE_LIST_KEY + "=" + whiteList,
            "-D" + Constant.HDFS_NUM_OF_THREAD_KEY + "=" + numOfThread,
            "-D" + Constant.HDFS_REMOTE_USER_KEY + "=" + hdfsUser, "-Dlog.file.name=hdfs_schema_fetch" };
    // delete the line (no kerberos needed): "-D" + Constant.HDFS_REMOTE_KEYTAB_LOCATION_KEY + "=" + hdfsKeyTab,
    ProcessBuilder pb = new ProcessBuilder(hadoopCmd);
    File logFile = new File(hdfsExtractLogFile);
    pb.redirectErrorStream(true);
    pb.redirectOutput(ProcessBuilder.Redirect.appendTo(logFile));
    Process process = pb.start();
    int pid = -1;
    if (process.getClass().getName().equals("java.lang.UNIXProcess")) {
        /* get the PID on unix/linux systems */
        try {
            Field f = process.getClass().getDeclaredField("pid");
            f.setAccessible(true);
            pid = f.getInt(process);
        } catch (Throwable e) {
        }
    }
    logger.info("executue command [PID=" + pid + "]: " + hadoopCmd);

    // wait until this process finished.
    int execResult = process.waitFor();

    // if the process failed, log the error and throw exception
    if (execResult > 0) {
        BufferedReader br = new BufferedReader(new InputStreamReader(process.getErrorStream()));
        String errString = "HDFS Metadata Extract Error:\n";
        String line = "";
        while ((line = br.readLine()) != null)
            errString = errString.concat(line).concat("\n");
        logger.error("*** Process  failed, status: " + execResult);
        logger.error(errString);
        throw new Exception("Process + " + pid + " failed");
    }

}

From source file:net.solarnetwork.node.dao.jdbc.derby.DerbyOnlineSyncJob.java

private void performSync(String dbPath) {
    assert syncCommand != null;
    List<String> cmd = new ArrayList<String>(syncCommand.size());
    for (String param : syncCommand) {
        param = param.replace(SOURCE_DIRECTORY_PLACEHOLDER, dbPath);
        param = param.replace(DESTINATION_DIRECTORY_PLACEHOLDER, destinationPath);
        cmd.add(param);/*from w  ww. ja  v a2 s.c  o m*/
    }
    if (log.isDebugEnabled()) {
        StringBuilder buf = new StringBuilder();
        for (String p : cmd) {
            if (buf.length() > 0) {
                buf.append(' ');
            }
            buf.append(p);
        }
        log.debug("Derby sync command: {}", buf.toString());
    }
    ProcessBuilder pb = new ProcessBuilder(cmd);
    BufferedReader in = null;
    PrintWriter out = null;
    try {
        Process pr = pb.start();
        pr.waitFor();
        if (pr.exitValue() == 0) {
            if (log.isDebugEnabled()) {
                in = new BufferedReader(new InputStreamReader(pr.getInputStream()));
                StringBuilder buf = new StringBuilder();
                String line = null;
                while ((line = in.readLine()) != null) {
                    buf.append(line).append('\n');
                }
                log.debug("Derby sync command output:\n{}", buf.toString());
            }
            log.info("Derby backup sync complete");
        } else {
            StringBuilder buf = new StringBuilder();
            in = new BufferedReader(new InputStreamReader(pr.getErrorStream()));
            String line = null;
            while ((line = in.readLine()) != null) {
                buf.append(line).append('\n');
            }
            log.error("Sync command returned non-zero exit code {}: {}", pr.exitValue(), buf.toString().trim());
        }
    } catch (IOException e) {
        throw new RuntimeException(e);
    } catch (InterruptedException e) {
        throw new RuntimeException(e);
    } finally {
        if (in != null) {
            try {
                in.close();
            } catch (IOException e) {
                // ignore
            }
        }
        if (out != null) {
            out.flush();
            out.close();
        }
    }

}

From source file:jeplus.EPlusWinTools.java

public static int runReadVars(EPlusConfig config, String WorkDir, String rvifile, String freq, String csvfile) {
    int ExitValue = -99;
    try {//from  w w  w  .jav  a  2 s .c  om
        Process EPProc;

        // Run EnergyPlus ReadVarsESO
        String CmdLine = config.getResolvedReadVars() + " \"" + rvifile + "\" " + freq + " unlimited";
        EPProc = Runtime.getRuntime().exec(
                new String[] { config.getResolvedReadVars(), rvifile, freq, "unlimited" }, null,
                new File(WorkDir));
        // Console logger
        try (PrintWriter outs = (config.getScreenFile() == null) ? null
                : new PrintWriter(new FileWriter(WorkDir + "/" + config.getScreenFile(), true));) {
            if (outs != null) {
                outs.println("# Calling ReadVarsESO - " + (new SimpleDateFormat()).format(new Date()));
                outs.println("# Command line: " + WorkDir + ">" + CmdLine);
                outs.flush();
            }
            StreamPrinter p_out = new StreamPrinter(EPProc.getInputStream(), "OUTPUT", outs);
            StreamPrinter p_err = new StreamPrinter(EPProc.getErrorStream(), "ERROR");
            p_out.start();
            p_err.start();
            ExitValue = EPProc.waitFor();
            p_out.join();
            p_err.join();
            // Copy the result file (eplusout.csv) to the target csv file name
            File csv = new File(WorkDir + EPlusConfig.getEPDefOutCSV());
            boolean ok = false;
            // Clear the existing output csv file
            File csvout = new File(WorkDir + csvfile);
            if (csvout.exists())
                csvout.delete();
            // Rename the new csv to the output csv
            if (csv.exists() && csv.renameTo(csvout)) {
                ok = true;
            }
            if (outs != null) {
                outs.println("# ReadVarsESO returns: " + ExitValue);
                outs.println(ok ? csv.getPath() + " renamed to " + csvfile
                        : "Processing " + rvifile + " has failed.");
                outs.flush();
            }
        }
        // set it to successful
        ExitValue = 0;
    } catch (IOException | InterruptedException ex) {
        logger.error("Error executing ReadVars.", ex);
    }
    return ExitValue;

}

From source file:com.xpn.xwiki.plugin.graphviz.GraphVizPlugin.java

/**
 * Executes GraphViz, writes the resulting image (in the requested format) in a temporary file on disk, and returns
 * the generated content from that file.
 * /*from  ww w  .j ava  2 s .  co m*/
 * @param hashCode the hascode of the content, to be used as the temporary file name
 * @param content the dot source code
 * @param extension the output file extension
 * @param dot which engine to execute: {@code dot} if {@code true}, {@code neato} if {@code false}
 * @return the content of the generated file
 * @throws IOException if writing the input or output files to the disk fails, or if writing the response body fails
 */
private byte[] getDotImage(int hashCode, String content, String extension, boolean dot) throws IOException {
    File dfile = getTempFile(hashCode, "input.dot", dot);
    if (!dfile.exists()) {
        FileUtils.write(dfile, content, XWiki.DEFAULT_ENCODING);
    }

    File ofile = getTempFile(hashCode, extension, dot);
    if (!ofile.exists()) {
        Runtime rt = Runtime.getRuntime();
        String[] command = new String[5];
        command[0] = dot ? this.dotPath : this.neatoPath;
        command[1] = "-T" + extension;
        command[2] = dfile.getAbsolutePath();
        command[3] = "-o";
        command[4] = ofile.getAbsolutePath();
        Process p = rt.exec(command);
        int exitValue = -1;
        final Thread thisThread = Thread.currentThread();
        Thread t = new Thread(new Hangcheck(thisThread), "dot-hangcheck");
        t.run();
        try {
            exitValue = p.waitFor();
            t.interrupt();
        } catch (InterruptedException ex) {
            p.destroy();
            LOGGER.error("Timeout while generating image from dot", ex);
        }

        if (exitValue != 0) {
            LOGGER.error("Error while generating image from dot: "
                    + IOUtils.toString(p.getErrorStream(), XWiki.DEFAULT_ENCODING));
        }
    }
    return FileUtils.readFileToByteArray(ofile);
}