[GROOVY-3494] @Immutable gives slightly vague error message if used on a class that cannot be made immutable

• Type: Improvement
• Status: Closed
• Priority: Trivial
• Resolution: Fixed
• Affects Version/s: 1.6.2
• Fix Version/s: 1.6.3, 1.7-beta-1
• Component/s: Compiler
• Assignee: Paul King
• Reporter: alpheratz
• Created: 29/Apr/09 06:44
• Updated: 07/Apr/15 19:13
• Resolved: 03/May/09 08:09

Description

Instead of:

Possible mutable field 'x' of type 'java.lang.Object' found while compiling
@Immutable class.

Maybe:

Possible mutable field 'x' of type 'java.lang.Object' found while compiling
@Immutable class; fields may only be other @Immutable classes, primitive
types or their associated wrappers (such as Integer, BigInteger, Double,
etc.), enums or other known immutable classes (such as java.awt.Color). Note
that any field defined as 'def' considered to be mutable and so cannot be
used in an @Immutable class.

or the less verbose:

All fields of @Immutable classes must be of a supported immutable type
but found field 'x' of type 'java.lang.Object' during compilation.

See also email thread:
http://markmail.org/thread/qr4allr73hpivm4q