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/ASTResolving.java
public static ITypeBinding guessBindingForReference(ASTNode node) {
		return Bindings.normalizeTypeBinding(getPossibleReferenceBinding(node));
	}
	private static ITypeBinding getPossibleReferenceBinding(ASTNode node) {
		ASTNode parent= node.getParent();
		switch (parent.getNodeType()) {
		case ASTNode.ASSIGNMENT:
			Assignment assignment= (Assignment) parent;
			if (node.equals(assignment.getLeftHandSide())) {
				
				return assignment.getRightHandSide().resolveTypeBinding();
			}
			
			return assignment.getLeftHandSide().resolveTypeBinding();
		case ASTNode.INFIX_EXPRESSION:
			InfixExpression infix= (InfixExpression) parent;
			InfixExpression.Operator op= infix.getOperator();
			if (op == InfixExpression.Operator.CONDITIONAL_AND || op == InfixExpression.Operator.CONDITIONAL_OR) {
				
				return infix.getAST().resolveWellKnownType("boolean"); 
			} else if (op == InfixExpression.Operator.LEFT_SHIFT || op == InfixExpression.Operator.RIGHT_SHIFT_UNSIGNED || op == InfixExpression.Operator.RIGHT_SHIFT_SIGNED) {
				
				return infix.getAST().resolveWellKnownType("int"); 
			}
			if (node.equals(infix.getLeftOperand())) {
				
				ITypeBinding rigthHandBinding= infix.getRightOperand().resolveTypeBinding();
				if (rigthHandBinding != null) {
					return rigthHandBinding;
				}