Groovy closure not work with static final field from super class

问题

class Parent {
    final static String newLine = "*"
}
class Child extends Parent{
    List body = [3, 4, 5]
    String toString() {
        def str = new StringBuilder()
        body.each { str.append(it + newLine) }
        str
    }
}

def c = new Child()
println c

The above is one trivial sample to illustrate the problem. It couldn't be compiled using Groovy plugin on Eclipse. Remove either final or static in the field of super class solves the problem. However, I have no idea why it's the case.

http://groovy.codehaus.org/Groovy+Beans In this link it mentions the rules for property and fields used in Groovy. I suppose the one applied should be the last one, i.e. meta class. Unfortunately, I still couldn't understand the behavior.

The behavior is reproduced consistently in all versions of Groovy. Maybe someone could report one bug to Groovy team. I have never done this before. It would be more efficient if someone experienced could do that.

回答1:

This is most probably http://jira.codehaus.org/browse/GROOVY-5776 which is more difficult to fix than it looks like

回答2:

As blackdrag already pointed out: it's a bug. But another workaround is to add the protected keyword:

protected final static String newLine = "*"

来源：https://stackoverflow.com/questions/14552964/groovy-closure-not-work-with-static-final-field-from-super-class