यह मेरा सहायक वर्ग साल के लिए उपयोग किया गया है। एक छोटी कक्षा JVM संसाधन लीक को ठीक करने के लिए इसमें JavaWorld streamgobbler क्लास है। पता नहीं है कि अभी भी JVM6 और JVM7 के लिए मान्य है लेकिन चोट नहीं पहुंचाता है। सहायक बाद के उपयोग के लिए आउटपुट बफर पढ़ सकते हैं।
import java.io.*;
/**
* Execute external process and optionally read output buffer.
*/
public class ShellExec {
private int exitCode;
private boolean readOutput, readError;
private StreamGobbler errorGobbler, outputGobbler;
public ShellExec() {
this(false, false);
}
public ShellExec(boolean readOutput, boolean readError) {
this.readOutput = readOutput;
this.readError = readError;
}
/**
* Execute a command.
* @param command command ("c:/some/folder/script.bat" or "some/folder/script.sh")
* @param workdir working directory or NULL to use command folder
* @param wait wait for process to end
* @param args 0..n command line arguments
* @return process exit code
*/
public int execute(String command, String workdir, boolean wait, String...args) throws IOException {
String[] cmdArr;
if (args != null && args.length > 0) {
cmdArr = new String[1+args.length];
cmdArr[0] = command;
System.arraycopy(args, 0, cmdArr, 1, args.length);
} else {
cmdArr = new String[] { command };
}
ProcessBuilder pb = new ProcessBuilder(cmdArr);
File workingDir = (workdir==null ? new File(command).getParentFile() : new File(workdir));
pb.directory(workingDir);
Process process = pb.start();
// Consume streams, older jvm's had a memory leak if streams were not read,
// some other jvm+OS combinations may block unless streams are consumed.
errorGobbler = new StreamGobbler(process.getErrorStream(), readError);
outputGobbler = new StreamGobbler(process.getInputStream(), readOutput);
errorGobbler.start();
outputGobbler.start();
exitCode = 0;
if (wait) {
try {
process.waitFor();
exitCode = process.exitValue();
} catch (InterruptedException ex) { }
}
return exitCode;
}
public int getExitCode() {
return exitCode;
}
public boolean isOutputCompleted() {
return (outputGobbler != null ? outputGobbler.isCompleted() : false);
}
public boolean isErrorCompleted() {
return (errorGobbler != null ? errorGobbler.isCompleted() : false);
}
public String getOutput() {
return (outputGobbler != null ? outputGobbler.getOutput() : null);
}
public String getError() {
return (errorGobbler != null ? errorGobbler.getOutput() : null);
}
//********************************************
//********************************************
/**
* StreamGobbler reads inputstream to "gobble" it.
* This is used by Executor class when running
* a commandline applications. Gobblers must read/purge
* INSTR and ERRSTR process streams.
* http://www.javaworld.com/javaworld/jw-12-2000/jw-1229-traps.html?page=4
*/
private class StreamGobbler extends Thread {
private InputStream is;
private StringBuilder output;
private volatile boolean completed; // mark volatile to guarantee a thread safety
public StreamGobbler(InputStream is, boolean readStream) {
this.is = is;
this.output = (readStream ? new StringBuilder(256) : null);
}
public void run() {
completed = false;
try {
String NL = System.getProperty("line.separator", "\r\n");
InputStreamReader isr = new InputStreamReader(is);
BufferedReader br = new BufferedReader(isr);
String line;
while ((line = br.readLine()) != null) {
if (output != null)
output.append(line + NL);
}
} catch (IOException ex) {
// ex.printStackTrace();
}
completed = true;
}
/**
* Get inputstream buffer or null if stream
* was not consumed.
* @return
*/
public String getOutput() {
return (output != null ? output.toString() : null);
}
/**
* Is input stream completed.
* @return
*/
public boolean isCompleted() {
return completed;
}
}
}
यहाँ एक उदाहरण .vbs स्क्रिप्ट लेकिन लिनक्स श स्क्रिप्ट के लिए इसी तरह के कार्यों से उत्पादन पढ़ने है।
ShellExec exec = new ShellExec(true, false);
exec.execute("cscript.exe", null, true,
"//Nologo",
"//B", // batch mode, no prompts
"//T:320", // timeout seconds
"c:/my/script/test1.vbs", // unix path delim works for script.exe
"script arg 1",
"script arg 2",
);
System.out.println(exec.getOutput());
इस [लेख] (http://www.javaworld.com/javaworld/jw-12-2000/jw-1229-traps.html) पर एक नज़र डालें। – kgiannakakis