Code that runs 4 'Street' processes:
for (int i=0; i < NUM_STREETS; i++) {
Process process = runtime.exec("java -classpath \\bin trafficcircle.Street 1 2");
InputStream is = process.getInputStream();
InputStreamReader isr = new InputStreamReader(is);
BufferedReader br = new BufferedReader(isr);
String line;
while ((line = br.readLine()) != null && !line.isEmpty()) {
System.out.println(line);
System.out.flush();
}
InputStream es = process.getErrorStream();
InputStreamReader esr = new InputStreamReader(es);
BufferedReader br2 = new BufferedReader(esr);
while ((line = br2.readLine()) != null && !line.isEmpty()) {
System.out.println(line);
System.out.flush();
}
int exitVal = process.waitFor();
System.out.println("Process exitValue: " + exitVal);
}
Where 'Street' is:
public class Street {
/**
* #param args
* 0 - Simulation run time
* 1 - Flow time interval
*/
public static void main(String[] args) {
System.out.println(args[0]);
System.out.println(args[1]);
System.out.flush();
}
}
Prints out:
Error: Could not find or load main class trafficcircle.Street
Process exitValue: 1
Error: Could not find or load main class trafficcircle.Street
Process exitValue: 1
Error: Could not find or load main class trafficcircle.Street
Process exitValue: 1
Error: Could not find or load main class trafficcircle.Street
Process exitValue: 1
'Street.class' in my Eclipse project is under \bin in package trafficcircle. I thought Runtime.exec would complain first if it wasn't found...what's up with this?
I assume you are getting an error which you are discarding. Try using ProcessBuilder.redirectErrorStream(true);
When you try to run a command it is not run in a shell, and may be getting an error which you don't see on the command line. I would explicitly use
"java","-classpath","bin","trafficcircle.Street","1","2"`
and make sure you are getting any error messages.
another option is to use a shell like
"/bin/bash", "-c", "java -classpath bin trafficcircle.Street 1 2"
Use ./bin (with a dot) to use relative paths.
Related
So I trying to use Runtime.getRuntime().exec to execute a openview command from Java code. This exact command runs fine on command prompt on the server does the necessary updates, but fails to perform when executed through Java code. The issue is that it returns exit status code of success i,e "0" when invoked through Java, but doesn't performs the updates it is suppose to do (appears like it is not executing).
Here is the command :
opcmsg application='Tester Down 11' object='My Support' severity=minor msg_grp='MyGroup' msg_text='DEV: -m=New Details:Request Detail description'
Here is the code :
String[] command = {
"opcmsg",
"application=\'Tester Down 11\'",
"object=\'My Support\'",
"severity=minor",
"msg_grp=\'MyGroup\'",
"msg_text=\'DEV: -m=New Details:Request Detail description\'"
}
p = Runtime.getRuntime().exec(command);
InputStream stderr = p.getErrorStream();
InputStreamReader isr = new InputStreamReader(stderr);
BufferedReader br = new BufferedReader(isr);
String errorDescription = null;
while ( (errorDescription = br.readLine()) != null)
LOGGER.info(errorDescription);
exitStatus = p.waitFor();
LOGGER.info("exitStatus : " + exitStatus);
This worked :
String[] command = { "/bin/sh",
"-c",
"opcmsg application=\'Tester Down 11\' object=\'My Support\' severity=minor msg_grp=\'MyGroup\' msg_text=\'DEV: -m=New Details:Request Detail description\' " }
I am executing grep command from java on a linux file. Its always returning null for the following code.
Process p;
String matchStr="testmatch";
String output = null;
try {
String command = "grep \""+matchStr+"\" "+ filename;
System.out.println("Running command: " + command);
p = Runtime.getRuntime().exec(command);
System.out.println("***********************************");
System.out.println("***********************************");
System.out.println("***********************************");
p.waitFor();
BufferedReader br = new BufferedReader(new InputStreamReader(p.getInputStream()));
while (br.readLine() != null) {
System.out.println("in while loop");
System.out.println("in while loop");
System.out.println("in while loop");
System.out.println(output);
System.out.println("***********************************");
System.out.println("***********************************");
System.out.println("***********************************");
System.out.println("***********************************");
// Process your output here
}
System.out.println("exit: " + p.exitValue());
p.destroy();
} catch (Exception e) {
e.printStackTrace();
}
If i grep it directly it shows output but from java it never gets into while loop.
Please suggest whats wrong here.
The problem is that you do not write anything to output so it stays null. I guess you have to rewrite your while loop like this
while ((output = br.readLine()) != null) {
// Process your output here
}
Take a note that this syntax is discouraged by most style check due to it's abmiguity
Also it's a good idea to place p.waitFor() after while loop so grep would not hang on flushig std(err|out).
UPDATE
Also it is a good idea to use ProcessBuilder (available since java-7) instead of Runtime.getRuntime().exec(...) because you will have more control over the process i.e
final ProcessBuilder builder = new ProcessBuilder();
builder.command("grep", matchStr, filename);
// redirect stderr to stdout
builder.redirectErrorStream(true);
final Process process = builder.start();
BufferedReader br = new BufferedReader(
new InputStreamReader(process.getInputStream()));
String output = null;
while ((output = br.readLine()) != null) {
System.out.println(output);
// Process your output here
}
process.waitFor();
After turning your code into a https://stackoverflow.com/help/mcve it works for me.
Here the file does not exist:
robert#habanero:~$ rm /home/robert/greptest.txt
robert#habanero:~$ javac GrepTest.java && java GrepTest
Running command: grep test /home/robert/greptest.txt
exit: 2
Now the file does exist but does not contain the text to be found:
robert#habanero:~$ echo not found > /home/robert/greptest.txt
robert#habanero:~$ javac GrepTest.java && java GrepTest
Running command: grep test /home/robert/greptest.txt
exit: 1
Now the file exists and contains the text:
robert#habanero:~$ echo test this > /home/robert/greptest.txt
robert#habanero:~$ javac GrepTest.java && java GrepTest
Running command: grep test /home/robert/greptest.txt
test this
exit: 0
Here is the code:
import java.io.*;
public class GrepTest {
public static void main(String[] args) throws Exception {
String command = "grep test /home/robert/greptest.txt";
System.out.println("Running command: " + command);
Process p = Runtime.getRuntime().exec(command);
p.waitFor();
BufferedReader br = new BufferedReader(new InputStreamReader(p.getInputStream()));
String output;
while ((output = br.readLine()) != null) {
System.out.println(output);
}
System.out.println("exit: " + p.exitValue());
p.destroy();
}
}
I was recently struggling with a similar issue, and I believe I the solution I found is an answer also to your problem (though your question is a bit malformed as others have pointed out).
The issue pertrains to the quote marks around your search string,
\""+matchStr+"\"
The java exec command will literally deliver these to the grep command, and instead of searching for matchStr, grep will be looking for "matchStr", and the results will not be what you are expecting.
This applies also in case one is executing the command as an array like
final Process process = Runtime.getRuntime().exec(new String[] { "grep", "-C1000", searchString, fileName } );
Pass the plain searchString without including quotation marks into the string.
Please tell me how to retrieve the status of autosys command from java program.
we can execute the commands using Runtime.getRuntime().exec(command) but how to get autosys status.
I am not sure about the autosys commend but if you can execute using the Runtime then you need to see the output of execution of command. If autosys will return something upon execution you will get it in out InputStream or error in ErrorStream in case of error.
Try something like this:
public static void printStream(InputStream is, String type){
try
{
InputStreamReader isr = new InputStreamReader(is);
BufferedReader br = new BufferedReader(isr);
String line=null;
while ( (line = br.readLine()) != null)
System.out.println(type + ">" + line);
} catch (IOException ioe){
ioe.printStackTrace();
}
}
public static void main(String args[])
{
String cmd = "command to execute";
Process proc = Runtime.getRuntime().exec(cmd);
printStream(proc.getInputStream(), "OUTPUT");
printStream(proc.getErrorStream(), "ERROR");
}
Process has a method exitValue() to get the exit value for the subprocess. exitValue
Example:
Runtime rt = Runtime.getRuntime();
Process process = rt.exec("ls -al");
process.waitFor();
System.out.println(process.exitValue());
I have the following bash script, example.sh that has some lines of code.To reproduce what I need let's say that I have in the script the following lines:
#!/bin/bash
echo First part of program
sleep 3
echo Second part of program
So, when I run this directly from terminal I get the first part printed to the screen(First part of program) then wait 3 seconds and after that I get the next part on the screen(Second part of program). When I run this in java, I execute the scipt, wait 3 seconds then I get both parts printed on screen. Is there a way to get the same effect as when running from terminal?
EDIT!
This is my code:
public void executeCommand(String command) {
String line;
StringBuffer output = new StringBuffer();
Process p;
try {
p = Runtime.getRuntime().exec(command);
p.waitFor();
BufferedReader reader = new BufferedReader(new InputStreamReader(p.getInputStream()));
line = "";
while ((line = reader.readLine())!= null) {
output.append(line + "\n");
}
setOutput(output.toString());
output = new StringBuffer();
BufferedReader error = new BufferedReader(new InputStreamReader(p.getErrorStream()));
line="";
while ((line = error.readLine())!= null) {
output.append(line + "\n");
}
setError(output.toString());
} catch (Exception e) {
e.printStackTrace();
}
}
If you start your script with the Process-Class then you can fetch the output of the script with for example:
ProcessBuilder pb = new ProcessBuilder("<bashname>", "<scriptpath>");
Process p = pb.start();
OutputStream ops = p.getOutputStream();
There must be the output immediatly.
SOLVED: redirect output and error into files using:
ProcessBuilder builder = new ProcessBuilder("sh",command);
builder.redirectOutput(new File("out.txt"));
builder.redirectError(new File("err.txt"));
try{
Process p = builder.start();
}catch(IOException e){
e.printStackTrace();
}
I am trying to execute a shell script with command line arguments using ProcessBuilder, this shell script inturn calls two other shell scripts that uses this argument. The first shell script runs fine, but when the second one is started it returns exit code 1.
ProcessBuilder snippet from Java Program:
//scenario - A string that holds a numerical value like 1 or 2 etc
String[] command2 = {"/bin/bash", "<path to shell script>/runTemporaryTestSuite.sh", scenario};
ProcessBuilder pb2 = new ProcessBuilder(command2);
Process p2 = pb2.start();
BufferedReader br = new BufferedReader(new InputStreamReader(p2.getInputStream()));
String line;
//print - is an object ref of response.getWriter() //
print.println("Output of running "+Arrays.toString(command2)+" is: ");
while ((line = br.readLine()) != null) {
print.println(line);
}
try {
int exitValue = p2.waitFor();
print.println("<br><br>Exit Value of p2 is " + exitValue);
} catch (InterruptedException e) {
e.printStackTrace();
}
runTemporaryTestSuite.sh
#!/bin/bash
sh <path to script>/clearRegressionResult.sh (This runs fine)
sh <path to script>/startRegression.sh $1 (This is where the issue occurs)
startRegression.sh looks like:
SUITE_PATH="./"
java -DconfigPath=${SUITE_PATH}/config.xml -Dscenario=$1 -Dauto=true -jar test.jar
My output:
Output of running [/bin/bash, /runTemporaryTestSuite.sh, 29] is:
Exit Value of p2 is 1
Any help in resolving this is really appreciated.
In think the problem is not that you cannot launch shell script with arguments, I was curious and I did a test
public class Main {
public static void main(String[] args) throws IOException {
String[] command = {"/bin/bash", "test.sh", "Argument1"};
ProcessBuilder p = new ProcessBuilder(command);
Process p2 = p.start();
BufferedReader br = new BufferedReader(new InputStreamReader(p2.getInputStream()));
String line;
System.out.println("Output of running " + command + " is: ");
while ((line = br.readLine()) != null) {
System.out.println(line);
}
}
here is the test.sh script
echo Hello im the script, here your args $#
Here the output
Output of running [Ljava.lang.String;#604e9f7f is:
Hello im the script, here your args Argument1
What I think is just that your startRegression.sh exit with a non-0 status (aka it failed somewhere) and it have repercussion, runTemporaryTestSuite.sh will also exit with a non-zero status, and so on hence the message : Exit Value of p2 is 1
What I see right now,
SUITE_PATH="./"
java -DconfigPath=${SUITE_PATH}/config.xml [..] the configPath will be .//config.xml so maybe you have a plain file not found issue? I might be wrong, hope it helped