org.omegahat.R.Java
Class RForeignReference

java.lang.Object
  |
  +--org.omegahat.Interfaces.NativeInterface.ForeignReference
        |
        +--org.omegahat.R.Java.RForeignReference

All Implemented Interfaces:

ForeignReferenceInt

Direct Known Subclasses:

REvaluator, RManualFunctionActionListener

public class RForeignReference

extends ForeignReference

This is the main class for an representing an S object in Java, where the S object is not copied to Java but stored within S and accessed in Java via this "proxy" reference. It is the base class for representing a Foreign Reference after it has been converted from a ForeignReference This instantiation occurs when the ForeignReference is evaluated, and potentially a new class is generated. Then an object of the necessary type that is derived from this class is created.

Fields inherited from class org.omegahat.Interfaces.NativeInterface.ForeignReference

evaluator, name

Constructor Summary

RForeignReference(ForeignReference id)

RForeignReference(ForeignReference id, OmegaInterfaceManager evaluator)

RForeignReference(java.lang.String id)
Create a reference with the specified name.

RForeignReference(java.lang.String id, OmegaInterfaceManager evaluator)
Create a reference with the specified identifier/name an register that its Omegahat evaluator is the given here.

Method Summary

java.lang.Object	localEval(org.omegahat.Environment.Parser.Parse.List args, java.lang.String methodName, java.lang.String returnClass, java.lang.String[] jsignature) The method that performs the call back to R to invoke the method named methodName on the object identified by this objects reference identifier (getReferenceName()).
java.lang.Object	reval(java.lang.String id, java.lang.Object[] args, java.lang.String methodName, java.lang.String returnClass, java.lang.String[] jsignature) Native method that invokes the "method" identified by methodName on the underlying S object (usually a closure), passing it the arguments given in the array args.

Methods inherited from class org.omegahat.Interfaces.NativeInterface.ForeignReference

convertResult, eval, getEvaluator, getReferenceName, processArg, processArgs, removeTemporaryAnonymousReferences, setEvaluator, setReferenceName, toString

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

RForeignReference

public RForeignReference(java.lang.String id)

Create a reference with the specified name.

RForeignReference

public RForeignReference(java.lang.String id,
                         OmegaInterfaceManager evaluator)

Create a reference with the specified identifier/name an register that its Omegahat evaluator is the given here. This is useful when there is more than one Omegahat evaluator and we want the methods of this reference to be evaluated within this Omegahat interpreter.

RForeignReference

public RForeignReference(ForeignReference id)

RForeignReference

public RForeignReference(ForeignReference id,
                         OmegaInterfaceManager evaluator)

Method Detail

localEval

public java.lang.Object localEval(org.omegahat.Environment.Parser.Parse.List args,
                                  java.lang.String methodName,
                                  java.lang.String returnClass,
                                  java.lang.String[] jsignature)
                           throws java.lang.Exception

The method that performs the call back to R to invoke the method named methodName on the object identified by this objects reference identifier (getReferenceName()). This then attempts to convert the answer R gave us to the one required by the method call that invoked this using convertResult.

reval

public java.lang.Object reval(java.lang.String id,
                              java.lang.Object[] args,
                              java.lang.String methodName,
                              java.lang.String returnClass,
                              java.lang.String[] jsignature)

Native method that invokes the "method" identified by methodName on the underlying S object (usually a closure), passing it the arguments given in the array args. This is usually called as the single entry point that allows Java to invoke methods in an object that is actually stored in S. So within a single Java class that is a reference to an S object, we may have multiple (possibly overloaded) methods and we implement each of these via a call to reval(). These pass their own signature with which they are defined, including the types of the arguments and the return type. Usually, these classes and their methods are generated programmatically via the byte-code compiler provided by Omegahat, ForeignReferenceClassGenerator.

Parameters:

the - identifier for this reference object

args - the array of arguments to pass to the S method

methodName - the name of the "method" within the S object to invoke

returnClass - the name of the return type expected.