Assertions

[Osama Hasan]

Article of

 
public class Foo1
{
  public void m1( int value )
  {
    assert  0 <= value;
    System.out.println( "OK" );
  }
  public static void main( String[] args )
  {
    Foo foo = new Foo();
    System.out.print( "foo.m1(  1 ): " );
    foo.m1( 1 );
    System.out.print( "foo.m1( -1 ): " );
    foo.m1( -1 );
  }
}
 

Any of the following commands enables assertion checking in class Foo:
1)java -ea Foo
2)java -ea:Foo Foo
3)java -ea:... Foo

I understood what 1 and 3 do.But what's the purpose bof writing the classname(Foo) two times in command no. 2.
Can any one explain?
Thanx in advance.

[Thomas Paul]

Osama, please change your display name to meet the JavaRanch naming requirements. You must use first name - space - last name.

[Shishio San]

I understood what 1 and 3 do.But what's the purpose bof writing the classname(Foo) two times in command no. 2.
Can any one explain?
Thanx in advance.

I think you mistyped the name of your class i.e Foo1 instead of Foo. Anyway the following command
java -ea:Foo Foo
runs the program called Foo with Assertions enable only in package Foo and its subpackages.
you might have a package called Foo then.

[Valentin Crettaz]

Originally posted by Thomas Paul:
Osama, please change your display name to meet the JavaRanch naming requirements. You must use first name - space - last name.

And here is the link:
Change your displayed name here

[Osama Hasan]

I am still confused.
I am running class Foo with the command line:
java -ea:Foo Foo
Although class Foo is not in the package "Foo" but still class Foo is running with assertions enabled.

[Jussi Sairanen]

Thought I'm not a professional on this particular issue, a quick search on the web found me this functionality for -ea:
<cut>
no arguments
Enables or disables assertions in all classes except system classes.
packageName...
Enables or disables assertions in the named package and any subpackages.
...
Enables or disables assertions in the unnamed package in the current working directory.
className
Enables or disables assertions in the named class
<cut>
--------------------
So java -ea:Foo Foo enables assertions for _class_ Foo not package, and runs the program Foo.

Jussi Sairanen