X-Git-Url: http://wamblee.org/gitweb/?a=blobdiff_plain;f=support%2Fgeneral%2Fsrc%2Fmain%2Fjava%2Forg%2Fwamblee%2Fio%2FSimpleProcess.java;fp=support%2Fgeneral%2Fsrc%2Fmain%2Fjava%2Forg%2Fwamblee%2Fio%2FSimpleProcess.java;h=6b922b93af1e0c43081dde79e79f581d7b683b40;hb=32a62ca2c752e33a7873ac868a7a1f289caedcd4;hp=0000000000000000000000000000000000000000;hpb=d2bdf4e813c6a3964958c87b2ce56eaadf8a1f0a;p=utils

diff --git a/support/general/src/main/java/org/wamblee/io/SimpleProcess.java b/support/general/src/main/java/org/wamblee/io/SimpleProcess.java
new file mode 100644
index 00000000..6b922b93
--- /dev/null
+++ b/support/general/src/main/java/org/wamblee/io/SimpleProcess.java
@@ -0,0 +1,153 @@
+package org.wamblee.io;
+
+import java.io.BufferedReader;
+import java.io.File;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.InputStreamReader;
+import java.io.OutputStream;
+import java.io.PrintStream;
+import java.io.StringWriter;
+import java.io.Writer;
+
+import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
+
+public class SimpleProcess {
+
+	private static final Log LOG = LogFactory.getLog(SimpleProcess.class);
+
+	private File _directory;
+
+	private String[] _cmd;
+	
+	private String _stdout; 
+	private String _stderr; 
+
+	public SimpleProcess(File aDirectory, String[] aCmd) {
+		_directory = aDirectory;
+		_cmd = aCmd;
+	}
+
+    /**
+     * @return the stdout
+     */
+    public String getStdout() {
+        return _stdout;
+    }
+    
+    /**
+     * @return the stderr
+     */
+    public String getStderr() {
+        return _stderr;
+    }
+    
+	/**
+	 * Runs the process and blocks until it is done.
+	 * 
+	 * @return Exit status of the process.
+	 * @throws IOException
+	 *             In case of problems.
+	 */
+	public int run() throws IOException {
+		return runImpl();
+	}
+
+	private int runImpl() throws IOException {
+		try {
+		    String fullcmd = ""; 
+		    for (String part: _cmd) {
+		        fullcmd += " " + part; 
+		    }
+			LOG.debug("Executing '" + fullcmd + "' in directory '" + _directory
+					+ "'");
+			java.lang.Process proc = Runtime.getRuntime().exec(_cmd, null, _directory);
+
+			// Read standard output and error in separate threads to avoid
+			// deadlock.
+
+            StringWriter stdout = new StringWriter();
+            StringWriter stderr = new StringWriter();
+			Thread stdoutReader = readAndLogStream("STDOUT>  ", proc
+					.getInputStream(), stdout);
+			Thread stderrReader = readAndLogStream("STDERR>  ", proc
+					.getErrorStream(), stderr);
+
+			try {
+				proc.waitFor();
+			} catch (InterruptedException e) {
+				IOException exception = new IOException(
+						"Process was terminated: " + this);
+				exception.initCause(e);
+				throw exception;
+			}
+			waitForReader(stdoutReader);
+			waitForReader(stderrReader);
+            
+            _stdout = stdout.toString();
+            _stderr = stderr.toString();
+
+			if (proc.exitValue() != 0) {
+				LOG.warn("Exit value was non-zero: " + this);
+			} else { 
+				LOG.debug("Process finished");
+			}
+			return proc.exitValue();
+		} catch (IOException e) {
+			IOException exception = new IOException("Error executing process: "
+					+ this);
+			exception.initCause(e);
+			throw exception;
+		}
+	}
+
+	private void waitForReader(Thread aReaderThread) {
+		try {
+			aReaderThread.join();
+		} catch (InterruptedException e) {
+			LOG
+					.warn(this
+							+ ": error waiting for output stream reader of process to finish");
+		}
+	}
+
+	private Thread readAndLogStream(final String aPrefix,
+			final InputStream aStream, final Writer aOutput) {
+		Thread inputReader = new Thread() {
+			@Override
+			public void run() {
+				BufferedReader br = null;
+				try {
+					br = new BufferedReader(new InputStreamReader(aStream));
+					String str;
+					while ((str = br.readLine()) != null) {
+						LOG.debug(aPrefix + str);
+                        aOutput.write(str);
+					}
+				} catch (IOException e) {
+					LOG.warn(SimpleProcess.this + ": error reading input stream", e);
+				} finally {
+					if (br != null) {
+						try {
+							br.close();
+						} catch (IOException e) {
+							LOG.warn("Error closing stream " + aPrefix);
+						}
+					}
+				}
+			}
+		};
+		inputReader.start();
+		return inputReader;
+	}
+
+	@Override
+	public String toString() {
+        String fullcmd = "";
+        for (String part: _cmd) { 
+            fullcmd += part + " ";
+        }
+		return "process(dir = '" + _directory + "', cmd = '" + fullcmd + "')";
+	}
+}