1.1 --- a/src/share/classes/com/sun/tools/javac/comp/Check.java Wed Mar 14 13:53:41 2012 -0700
1.2 +++ b/src/share/classes/com/sun/tools/javac/comp/Check.java Mon Mar 26 15:27:51 2012 +0100
1.3 @@ -516,6 +516,35 @@
1.4 found, req);
1.5 }
1.6 }
1.7 +
1.8 + /** Check for redundant casts (i.e. where source type is a subtype of target type)
1.9 + * The problem should only be reported for non-292 cast
1.10 + */
1.11 + public void checkRedundantCast(Env<AttrContext> env, JCTypeCast tree) {
1.12 + if (!tree.type.isErroneous() &&
1.13 + (env.info.lint == null || env.info.lint.isEnabled(Lint.LintCategory.CAST))
1.14 + && types.isSameType(tree.expr.type, tree.clazz.type)
1.15 + && !is292targetTypeCast(tree)) {
1.16 + log.warning(Lint.LintCategory.CAST,
1.17 + tree.pos(), "redundant.cast", tree.expr.type);
1.18 + }
1.19 + }
1.20 + //where
1.21 + private boolean is292targetTypeCast(JCTypeCast tree) {
1.22 + boolean is292targetTypeCast = false;
1.23 + JCExpression expr = TreeInfo.skipParens(tree.expr);
1.24 + if (expr.hasTag(APPLY)) {
1.25 + JCMethodInvocation apply = (JCMethodInvocation)expr;
1.26 + Symbol sym = TreeInfo.symbol(apply.meth);
1.27 + is292targetTypeCast = sym != null &&
1.28 + sym.kind == MTH &&
1.29 + (sym.flags() & POLYMORPHIC_SIGNATURE) != 0;
1.30 + }
1.31 + return is292targetTypeCast;
1.32 + }
1.33 +
1.34 +
1.35 +
1.36 //where
1.37 /** Is type a type variable, or a (possibly multi-dimensional) array of
1.38 * type variables?
