com.oracle.truffle.api.interop

Annotation Type CanResolve

@Target(value=TYPE)
 @Retention(value=SOURCE)
public @interface CanResolve

Annotation to put on your node to provide a language check for the receiver object. There must be only one element with this annotation on it. This node needs to be an abstract class. Sub-classes will be automatically generated, which is similar to Truffle's DSL for node specialization. The node needs to define one test method, which implement the receiver language check.

@MessageResolution(receiverType = ExampleTruffleObject.class)
public static class ExampleTruffleObjectMR {

     @Resolve(message = "READ")
     public abstract static class ExampleReadNode extends Node {

         protected Object access(ExampleTruffleObject receiver,
                                 String name) {
             if (ExampleTruffleObject.MEMBER_NAME.equals(name)) {
                 return receiver.getValue();
             }
             throw UnknownIdentifierException.raise(name);
         }
     }

    @Resolve(message = "WRITE")
    public abstract static class ExampleWriteNode extends Node {

        protected static int access(ExampleTruffleObject receiver,
                                    String name, int value) {
            if (ExampleTruffleObject.MEMBER_NAME.equals(name)) {
                receiver.setValue(value);
                return value;
            }
            throw UnknownIdentifierException.raise(name);
        }
    }

    @CanResolve
    public abstract static class Check extends Node {

        protected static boolean test(TruffleObject receiver) {
            return receiver instanceof ExampleTruffleObject;
        }
    }

}

Since:

0.13