getter for enum constants in JDefinedClass

[glassfishrobot]

When using a visitor pattern to generate classes (enums), it would be helpful to get the map of enum constants
from JDefinedClass defined so far.

I would much appreciate the introduction of a method like:

public Map<String, JEnumConstant> getEnumConstantsByName()

{ return Collections.unmodifiableMap(enumConstantsByName); }

[glassfishrobot]

Reported by hubert_wagener

[glassfishrobot]

This issue was imported from java.net JIRA CODEMODEL-5