[GROOVY-3749] Cannot have a script with a main method as the starting point

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 1.7-beta-1
• Fix Version/s: 1.7-beta-2, 1.6.6
• Component/s: Compiler
• Environment: Groovy Version: 1.7-beta-2-SNAPSHOT JVM: 1.5.0_06 (Windows XP)
• Assignee: Roshan Dawrani
• Reporter: Roshan Dawrani
• Created: 15/Sep/09 21:46
• Updated: 15/Oct/09 17:17
• Resolved: 02/Oct/09 13:47

Description

Can a groovy script not provide its main() method?

Case 1: If I run the following script, nothing happens:

static main(args) {
    println "Roshan"
}

Doing a javap on the generated class, I see it now has duplicate definitions of main(), as:

public static void main(java.lang.String[]); // groovy generated
public static java.lang.Object main(java.lang.String[]); // one provided in the script

In the above script nothing is happening because groovy invokes its own main(), which is effectively empty here.

Case 2: If I change the script to:

static void main(args) {
    println "Roshan"
}

then it fails saying

Repetitive method name/signature for method 'void main(java.lang.Object)' in class 'Try'.

So, there is no way I can write a script that has main() as the starting point.

First case produces an invalid class and second case also does not allow the user to provide his own main() starting point.