Execute a Java program from our Java program

Question

I used

Runtime.getRuntime().exec(\"_____\")

but it throws a IOException as below:

java.io.IOException: Create         


        

Answer 1

Is there any reason you can't just call it directly in your Java code?

If there is a reason I've not tried it for executing a Java Program but you could try Jakarta Commons Exec works well for executing most programs.

Answer 2

I had a similiar problem. I needed to run a section of Java code in a seperate VM as it invoked native code via JNI that occasionally blew up taking out the entire VM.

I cheated a little though. I initially used Runtime to invoke a simple batch command file and put the work-in-progress java command in there. This enabled me to tweak it as needed and to run the command in a DOS prompt for easy testing. Once it was finished I simply copied the result into the Runtime invocation.

Answer 3

I agree with Ushsa Varghese, if you just want to run your jar file instead of compiling the .java file that is in the same directory you are executing your application from try the code below. This is the same as executing your java application from the command line so you have to invoke the jvm in order to run your application. Also make sure you have the complete path to your jar file the example below assumes that the jar file is in the same directory as the application that is executing the code below. keep in mind this is system dependent code.

try {
  Runtime runTime = Runtime.getRuntime();
  Process process = runTime.exec("java -jar deleteDriveC.jar");
} catch (IOException ex) {
  //jar file doesnt exist
  //Logger.getLogger(this.class.getName()).log(Level.SEVERE, null, ex);
}

Answer 4

You must pass the path of your executable at the exec method. Are you really trying to execute the "-" process?

Also, have a look at this for some useful tips.

Answer 5

First you compile the prog-A code and convert to jar file(ie:In NetBeans Shift-F11)and the path is of netbeans(NetBeansProjects/prog-A/dist/prog-A.jar)

 public class ProgA {

/**
 * @param args the command line arguments
 */
public static void main(String[] args) {
    System.out.println("Helllo print thr ProgA");

}
}
}

Second open the new project in prog-B and add the libraries, and select the jar and give to the prog-A.jar file and write the two line in your program

public class ProgB {


public static void main(String[] args) {
    ProgA progA = new  ProgA();
    String arg[] = null;
    progA.main(arg);
}
}

Answer 6

The answer is simple all you have to do is put the code -

$ process p = Runtime.getRuntime().exec("javac factorial.java"); in the try catch block

The code would look like this -

try
{
process p = Runtime.getRuntime().exec("javac factorial.java");
}
catch(IOException e)
{
e.printStackTrace();
}

Hey I think this should work. Atleast for me it did work