run a .class file at run time from another java file

[ketan]

Hello All,

I want to run a .class file at run time from another java file ,,, plz help me how can i code for this,,,,
moreover if that .class file doesnt contain "main", is it feasible to run using "main" of this caller java file....


Thanks in advance!

Ketan

[dinesh.guntha]

Runtime.getRuntime().exec(cmd c:\java file.java);
but it should contain the main method then only it will run

[Norm]

I want to run a .class file at run time from another java file

Call the class's constructor if it has a public one:

TheClassName = new TheClassName(????); // call the class's constructor

Otherwise you need to know the name of a static method in the class that you can call like the main class:

TheClassName.main(new String[]{}); // call the class's main method

[ketan]

Hello Dinesh, Norm,
Thanks for replying. Actually I dont have source code(java file) of that file in my system , I have only class file that i need to run by writing code for it.... please suggest

[dinesh.guntha]

Hello Ketan,

Create a java class with main then call that class in this main class it will work i think so,

For example Dog.class

Class Anaimal {
public static void main(String args[]){
Dog g = new Dog();
g // u can access the all the other than private access specifier
}
} or
By using the reflection you can access class

you can try with the reflection i think so

[ketan]

Thanks Dinesh! There is some issue in this ,,,,,,,
This code will look for Dog class at compile time, but Dog.class file wont be available before compilation,,,,

[Norm]

Put the Dog class file on the classpath during compilation.

[ketan]

hey , i was able to do it using reflection.... Thanks a lot Dinesh and Norm :)