Java throwing IOexception when running Main Method from another Clas

[GDRRiley]

So I'm calling the main methods of other classes and I get this. Me rewriting the other programs isn't going to be easy as they both have dozens of inputs.

Spoiler

java.io.IOException: Cannot run program "walkTheCity.java": error=2, No such file or directory
    at java.lang.ProcessBuilder.start(ProcessBuilder.java:1047)
    at java.lang.Runtime.exec(Runtime.java:617)
    at java.lang.Runtime.exec(Runtime.java:450)
    at java.lang.Runtime.exec(Runtime.java:347)
    at gabrielGameLauncher.main(gabrielGameLauncher.java:13)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:606)
    at edu.rice.cs.drjava.model.compiler.JavacCompiler.runCommand(JavacCompiler.java:272)

  import java.util.Scanner;
  import java.io.IOException;
public class gabrielGameLauncher{
  
  public static void main(String[] args) throws IOException{
    Scanner scan= new Scanner(System.in);
    System.out.println("Enter 1 to play walk in the City.\nEnter 2 to play a cave adventure game.\nEnter 0 to stop playing.");
    int gchoice=1;
      while(gchoice!=0){
    gchoice=scan.nextInt();
    if(gchoice==1||gchoice==2){
    // compiles code
      Process g1 = Runtime.getRuntime().exec("walkTheCity.java");
      Process g2 = Runtime.getRuntime().exec("AdventureGameS2.java");
      Process processRun = null;
      
      //the 2 code runners
      if(gchoice==1){
      processRun = null;
      processRun = Runtime.getRuntime().exec("walkTheCity");
      
      }
      if(gchoice==2){
      processRun = null;
      processRun = Runtime.getRuntime().exec("AdventureGameS2");

      }
    }
    if(gchoice!=0)
    System.out.println("Enter another code to play a game.");
    }
    System.out.println("Thanks for playing hope you had a great time.");
  }
}

Thanks for any help

[panther420]

1 minute ago, GDRRiley said:

So I'm calling the main methods of other classes and I get this. Me rewriting the other programs isn't going to be easy as they both have dozens of inputs.

  Hide contents

java.io.IOException: Cannot run program "walkTheCity.java": error=2, No such file or directory
    at java.lang.ProcessBuilder.start(ProcessBuilder.java:1047)
    at java.lang.Runtime.exec(Runtime.java:617)
    at java.lang.Runtime.exec(Runtime.java:450)
    at java.lang.Runtime.exec(Runtime.java:347)
    at gabrielGameLauncher.main(gabrielGameLauncher.java:13)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:606)
    at edu.rice.cs.drjava.model.compiler.JavacCompiler.runCommand(JavacCompiler.java:272)

  import java.util.Scanner;
  import java.io.IOException;
public class gabrielGameLauncher{
  
  public static void main(String[] args) throws IOException{
    Scanner scan= new Scanner(System.in);
    System.out.println("Enter 1 to play walk in the City.\nEnter 2 to play a cave adventure game.\nEnter 0 to stop playing.");
    int gchoice=1;
      while(gchoice!=0){
    gchoice=scan.nextInt();
    if(gchoice==1||gchoice==2){
    // compiles code
      Process g1 = Runtime.getRuntime().exec("walkTheCity.java");
      Process g2 = Runtime.getRuntime().exec("AdventureGameS2.java");
      Process processRun = null;
      
      //the 2 code runners
      if(gchoice==1){
      processRun = null;
      processRun = Runtime.getRuntime().exec("walkTheCity");
      
      }
      if(gchoice==2){
      processRun = null;
      processRun = Runtime.getRuntime().exec("AdventureGameS2");

      }
    }
    if(gchoice!=0)
    System.out.println("Enter another code to play a game.");
    }
    System.out.println("Thanks for playing hope you had a great time.");
  }
}

Thanks for any help

This is kind of a trivial one, but did you ensure that the walkTheCity.java file is in the same directory as your GameLauncher file calling it? And did you ensure everything is spelled correctly? It's saying that it can't find the file, so I'd verify that it's there first.

[GDRRiley]

Just now, panther420 said:

This is kind of a trivial one, but did you ensure that the walkTheCity.java file is in the same directory as your GameLauncher file calling it? And did you ensure everything is spelled correctly? It's saying that it can't find the file, so I'd verify that it's there first.

yep there all in the same folder and all open in Dr Java.

[panther420]

5 minutes ago, GDRRiley said:

yep there all in the same folder and all open in Dr Java.

Then it seems like the better way to load the main method from another class would be to call it directly. According to the java docs the exec() method you're calling is for console commands, so perhaps you would use "java walkTheCity.java" instead of just the file name. But assuming both files are in the same package you should just be able to call walkTheCity.main() from gabrielGameLauncher. See here: https://stackoverflow.com/questions/13174031/how-to-run-java-class-file-from-another-class-file-java-newb.

 

EDIT: the code would probably look like this:

public class gabrielGameLauncher{
  
  public static void main(String[] args) throws IOException{
    Scanner scan= new Scanner(System.in);
    System.out.println("Enter 1 to play walk in the City.\nEnter 2 to play a cave adventure game.\nEnter 0 to stop playing.");
    int gchoice=1;
    while(gchoice!=0){
      gchoice=scan.nextInt();
      // run code based on decision
      if(gchoice==1){
      	walkTheCity.main(); // pass any args necessary here
      }
      if(gchoice==2){
        AdventureGameS2.main();
      }
      if(gchoice!=0){
      System.out.println("Enter another code to play a game.");
      }
    }
    System.out.println("Thanks for playing hope you had a great time.");
  }
}

 

[GDRRiley]

3 minutes ago, panther420 said:

Then it seems like the better way to load the main method from another class would be to call it directly. According to the java docs the exec() method you're calling is for console commands, so perhaps you would use "java walkTheCity.java" instead of just the file name. But assuming both files are in the same package you should just be able to call walkTheCity.main() from gabrielGameLauncher. See here: https://stackoverflow.com/questions/13174031/how-to-run-java-class-file-from-another-class-file-java-newb.

ok that worked. just had to remove String[] args from my main method in each of the programs. 

[panther420]

Just now, GDRRiley said:

ok that worked. just had to remove String[] args from my main method in each of the programs. 

Cool. You should mark the post as solved and highlight a correct answer for future reference.

[GDRRiley]

Just now, panther420 said:

Cool. You should mark the post as solved and highlight a correct answer for future reference.

I did it isn't my first time on this forum if you couldn't tell from post or badges. 

[panther420]

Just now, GDRRiley said:

I did it isn't my first time on this forum if you couldn't tell from post or badges. 

True. Sorry about that.