Bug 82940 [quick fix] Missing sensible conversion suggestion
For this code > % cat Test.java import java.util.Collections; import java.util.List; public class Test { interface Wrapper { int doit(); } private static final List<Wrapper> STD_WRAPPERS = Collections.singletonList ((Wrapper)new Wrapper() { public int doit() { return 0; } }); private static final List<Wrapper> STD_WRAPPERS2 = Collections.singletonList (new Wrapper() { public int doit() { return 0; } }); } The value passed Collections.singletonList is actually of the right type so a sensible conversion would be to put in the cast (see the difference between the 2 statics). The current quick fixes offered assume the type being assigned to is wrong (when infact it is right). A useful quick fix would be to cast the parameter to the right type to give the left type (this would help with any 1 arg method of the form X<T> method(T)
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/text/correction/UnresolvedElementsSubProcessor.java
if (targetCU != null) {
			boolean isDifferentCU= !cu.equals(targetCU);
			if (isImplicitConstructor(methodDecl, targetCU)) {
				return;
			}
			ChangeDescription[] changeDesc= new ChangeDescription[argTypes.length];
			ITypeBinding[] changeTypes= new ITypeBinding[diff];
			for (int i= diff - 1; i >= 0; i--) {
				int idx= indexSkipped[i];
				Expression arg= (Expression) arguments.get(idx);
				String name= arg instanceof SimpleName ? ((SimpleName) arg).getIdentifier() : null;
				ITypeBinding newType= Bindings.normalizeTypeBinding(argTypes[idx]);
				if (newType == null) {
					newType= astRoot.getAST().resolveWellKnownType("java.lang.Object"); 
				}
				if (!ASTResolving.isUseableTypeInContext(newType, methodDecl, false)) {
					return;
				}
				changeDesc[idx]= new InsertDescription(newType, name);
				changeTypes[i]= newType;
			}
			String[] arg= new String[] { ASTResolving.getMethodSignature(methodDecl, isDifferentCU), getTypeNames(changeTypes) };
			String label;
			if (methodDecl.isConstructor()) {
				if (diff == 1) {
					label= Messages.format(CorrectionMessages.UnresolvedElementsSubProcessor_addparam_constr_description, arg);
				} else {
					label= Messages.format(CorrectionMessages.UnresolvedElementsSubProcessor_addparams_constr_description, arg);
				}
			} else {