Package org.drools.mvel.asm

Class MethodComparator

java.lang.Object

org.drools.mvel.asm.MethodComparator

public class MethodComparator
extends java.lang.Object

The purpose of this utility it to check if 2 method implementations are equivalent, by comparing the bytecode. This essentual for node sharing where java semantics are involved.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	MethodComparator.Tracer

Constructor Summary

Constructors

Constructor	Description
MethodComparator()

Method Summary

Modifier and Type	Method	Description
static boolean	compareBytecode(java.lang.String b1, java.lang.String b2)	Compares 2 bytecode listings.
boolean	equivalent(java.lang.String method1, org.mvel2.asm.ClassReader class1, java.lang.String method2, org.mvel2.asm.ClassReader class2)	This actually does the comparing.
static java.lang.String	getMethodBytecode(java.lang.Class cls, java.lang.String ruleClassName, java.lang.String packageName, java.lang.String methodName, java.lang.String resource)
static java.lang.String	getMethodBytecode(java.lang.String methodName, byte[] bytes)	This will return a series of bytecode instructions which can be used to compare one method with another.
java.lang.String	getMethodBytecode(java.lang.String methodName, org.mvel2.asm.ClassReader classReader)	This will return a series of bytecode instructions which can be used to compare one method with another.

Methods inherited from class java.lang.Object

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

Constructor Detail

MethodComparator

public MethodComparator()

Method Detail

equivalent

public boolean equivalent(java.lang.String method1,
                          org.mvel2.asm.ClassReader class1,
                          java.lang.String method2,
                          org.mvel2.asm.ClassReader class2)

This actually does the comparing. Class1 and Class2 are class reader instances to the respective classes. method1 and method2 are looked up on the respective classes and their contents compared. This is a convenience method.

getMethodBytecode

public java.lang.String getMethodBytecode(java.lang.String methodName,
                                          org.mvel2.asm.ClassReader classReader)

This will return a series of bytecode instructions which can be used to compare one method with another. debug info like local var declarations and line numbers are ignored, so the focus is on the content.

getMethodBytecode

public static java.lang.String getMethodBytecode(java.lang.String methodName,
                                                 byte[] bytes)

This will return a series of bytecode instructions which can be used to compare one method with another. debug info like local var declarations and line numbers are ignored, so the focus is on the content.

compareBytecode

public static boolean compareBytecode(java.lang.String b1,
                                      java.lang.String b2)

Compares 2 bytecode listings. Returns true if they are identical.

getMethodBytecode

public static java.lang.String getMethodBytecode(java.lang.Class cls,
                                                 java.lang.String ruleClassName,
                                                 java.lang.String packageName,
                                                 java.lang.String methodName,
                                                 java.lang.String resource)