jist.runtime
Class RewriterTraversalModifyEntityInvocation

java.lang.Object
  jist.runtime.ClassTraversal.Empty
      jist.runtime.RewriterTraversalModifyEntityInvocation

All Implemented Interfaces:

ClassTraversal.Visitor

 class RewriterTraversalModifyEntityInvocation
extends ClassTraversal.Empty

Traversal object that intercepts any method invocation instructions to entity objects. This conversion is a little bit tricky, because it involves a bit more bytecode generation. The basic idea has three parts. First, the appropriate method object is selected from the corresponding method stub field. Second, corresponding entity reference (or entity, in the case of a "this." call) is passed along. Lastly, all the invocation parameters on the stack are placed an object array of the appropriate size. Primitive types are first converted into their object equivalents.

Since:

JIST1.0

Author:

Rimon Barr <barr+jist@cs.cornell.edu>

See Also:

Controller.newEntityReference(jist.runtime.Entity), JistAPI.Entity, EntityRef

Field Summary

private org.apache.bcel.generic.ConstantPoolGen	cpg class constant pool.
private org.apache.bcel.generic.InstructionFactory	ifc class instruction factory.
private Rewriter	rewriter primary rewriter.

Constructor Summary

RewriterTraversalModifyEntityInvocation(Rewriter rewriter)
Create rewriter object to modify entity invocation points.

Method Summary

org.apache.bcel.generic.ClassGen	doClass(org.apache.bcel.generic.ClassGen cg) Upcall to process class before field and method processing.
void	doInstruction(org.apache.bcel.generic.ClassGen cg, org.apache.bcel.generic.MethodGen mg, org.apache.bcel.generic.InstructionHandle ih, org.apache.bcel.generic.Instruction inst) Upcall to process instruction. Note that instructions can be inserted and deleted directly using the BCEL API, and therefore this method returns void.
private void	packParametersIntoArray(org.apache.bcel.generic.InstructionList il, org.apache.bcel.generic.Type[] args, org.apache.bcel.generic.MethodGen mg, org.apache.bcel.generic.InstructionHandle ih) Insert code to pack method parameters into object array.

Methods inherited from class jist.runtime.ClassTraversal.Empty

doClassPost, doField, doMethod, doMethodPost

Methods inherited from class java.lang.Object

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

Field Detail

ifc

private org.apache.bcel.generic.InstructionFactory ifc

class instruction factory.

cpg

private org.apache.bcel.generic.ConstantPoolGen cpg

class constant pool.

rewriter

private Rewriter rewriter

primary rewriter.

Constructor Detail

RewriterTraversalModifyEntityInvocation

public RewriterTraversalModifyEntityInvocation(Rewriter rewriter)

Create rewriter object to modify entity invocation points.

Parameters:

rewriter - reference to primary rewriter

Method Detail

doClass

public org.apache.bcel.generic.ClassGen doClass(org.apache.bcel.generic.ClassGen cg)

Upcall to process class before field and method processing.

Specified by:

doClass in interface ClassTraversal.Visitor

Overrides:

doClass in class ClassTraversal.Empty

Parameters:

cg - BCEL class generator object to process

Returns:

processed BCEL class generator object

packParametersIntoArray

private void packParametersIntoArray(org.apache.bcel.generic.InstructionList il,
                                     org.apache.bcel.generic.Type[] args,
                                     org.apache.bcel.generic.MethodGen mg,
                                     org.apache.bcel.generic.InstructionHandle ih)
                              throws java.lang.ClassNotFoundException

Insert code to pack method parameters into object array.

Parameters:

il - instruction list

args - method arguments

mg - method object

ih - instruction handle

Throws:

java.lang.ClassNotFoundException

doInstruction

public void doInstruction(org.apache.bcel.generic.ClassGen cg,
                          org.apache.bcel.generic.MethodGen mg,
                          org.apache.bcel.generic.InstructionHandle ih,
                          org.apache.bcel.generic.Instruction inst)
                   throws java.lang.ClassNotFoundException

Upcall to process instruction. Note that instructions can be inserted and deleted directly using the BCEL API, and therefore this method returns void.

Specified by:

doInstruction in interface ClassTraversal.Visitor

Overrides:

doInstruction in class ClassTraversal.Empty

Parameters:

cg - BCEL class generator object

mg - BCEL method generator object

ih - BCEL instruction handle object to process

inst - BCEL instruction object to process

Throws:

java.lang.ClassNotFoundException