When to use system.exit(0)? [duplicate]

问题

Possible Duplicate:
Difference in System. exit(0) , System.exit(-1), System.exit(1 ) in java

Can anyboby please explain the use of system.exit(0)?
What will happen internaly when we call this method especially the argument value? 0,1,2,3.. etc

回答1:

System.exit will ask the VM process to stop, and the code returned will be the code given in parameter. Common codes are: 0 for success, 1 to 127 for error, 128-255 is used by Unix and mapped to signals.

回答2:

System.exit(int) shuts down the JVM, providing an 'exit code' of 0.

The exit code is the JVM process's return value.

Usually in Unix systems, an exit code of 0 indicates a normal shutdown, and anything that is not zero indicates the shutdown was caused by an error.

See Wikipedia for more information:

http://en.wikipedia.org/wiki/Exit_status

回答3:

The input to System.exit is your error code. A value of 0 means normal exit. A non zero number will indicate abnormal termination. This number can be up to you. Perhaps if you want to exit if you cannot read a file you could use error code =1, if you cannot read from a socket it could be error code = 2.

System.exit will terminate the VM and so your program.

A typical example could be below. If the runMyApp throws an exception where you want to cause the program to exit.

public static void main(String... args) {
   try {
      runMyApp();
   } catch (Exception e) {
      System.exit(1);
   }
}

来源：https://stackoverflow.com/questions/12893350/when-to-use-system-exit0

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java

core