fr.umlv.jmmf.reflect
Class MultiMethod

java.lang.Object
  |
  +--java.lang.reflect.AccessibleObject
        |
        +--fr.umlv.jmmf.reflect.MultiMethod

All Implemented Interfaces:

java.lang.reflect.Member

public class MultiMethod

extends java.lang.reflect.AccessibleObject

implements java.lang.reflect.Member

an implementation of the multi-method. This class support the 1.2 security model. The current implementation of the multi-method mecanism desactivate default Java language access control checks.

Version:

0.4pre8

Author:

Remi Forax

See Also:

class Test {
  interface A {}
  class B implemnts A {}
  class C implements A
  { int value; }

  static public String toString(B b) 
  { return b.toString(); }
  static public String toString(C c)
  { return String.valueOf(c.value); }

  public static void main(String[] args)
    throw Throwable
  {
    MultiMethod mm=new MultiMethod("toString",Test.class);

    A a=new B();
    System.out.println(mm.invoke(null,new Object[]{a}));
    a=new C();
    System.out.println(mm.invoke(null,new Object[]{a}));

    Method method=mm.asMethod();
    System.out.println(method);
    System.out.println(method.invoke(null,new Object[]{a}));
  }
}

Fields inherited from interface java.lang.reflect.Member

DECLARED, PUBLIC

Method Summary

java.lang.reflect.Method	asMethod() return a Java Method object that corresponding to the current multi-method. this method is dynamically generated.
java.lang.reflect.Method	asMethod(java.lang.ClassLoader loader) return a Java Method object that corresponding to the current multi-method. this method is dynamically generated.
static MultiMethod	create(java.lang.Class clazz, java.lang.String name, int argLength) construct a multi-method by taking all method named name with argLength parameter(s) in class clazz.
static MultiMethod	create(java.lang.Class clazz, java.lang.String name, int argLength, boolean onlyPublic) construct a multi-method by taking all method named name with argLength parameter(s) in class clazz.
boolean	equals(java.lang.Object o) Compares this MultiMethod against the specified object.
java.lang.Class	getDeclaringClass() return class that contains all methods of the current multi-method.
java.lang.Class[]	getExceptionTypes() return the exception types of the current method.
int	getModifiers() returns the Java language modifiers for the multi-method represented by this MultiMethod object, as an integer.
java.lang.String	getName() return the name of the current multi-method.
java.lang.Class[]	getParameterTypes() return the parameter types of the current method. a parameter type is the lowest common subtype of all parameter types of the methods that composed the multi-method.
java.lang.Class	getReturnType() return the return type of the current method. a return type is the lowest common subtype of all return types of the methods that composed the multi-method.
int	hashCode() Returns a hashcode for this MultiMethod.
java.lang.Object	invoke(java.lang.Object target, java.lang.Object[] args) call the best method of the multi-method according to the type of all items if args array on a specified target object.
java.lang.Object	invoke(java.lang.Object target, java.lang.Object[] args, java.lang.Class[] types) call the best method of the multi-method according to the type of all items if args array on a specified target object.
java.lang.String	toString() return a string representation of the multi-method.

Methods inherited from class java.lang.reflect.AccessibleObject

isAccessible, setAccessible, setAccessible

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Method Detail

equals

public boolean equals(java.lang.Object o)

Compares this MultiMethod against the specified object. Returns true if the objects are the same. Two MultiMethods are the same if they were declared by the same class and have the same name and formal parameter types and return type.

Overrides:

equals in class java.lang.Object

hashCode

public int hashCode()

Returns a hashcode for this MultiMethod. The hashcode is computed as the exclusive-or of the hashcodes for the underlying method's declaring class name and the method's name.

Overrides:

hashCode in class java.lang.Object

toString

public java.lang.String toString()

return a string representation of the multi-method.

Overrides:

toString in class java.lang.Object

invoke

public java.lang.Object invoke(java.lang.Object target,
                               java.lang.Object[] args)
                        throws java.lang.IllegalAccessException,
                               java.lang.reflect.InvocationTargetException,
                               NoMatchingMethodException,
                               MultipleMatchingMethodsException

call the best method of the multi-method according to the type of all items if args array on a specified target object.

Parameters:

target - object on which the best method is called.

args - arguments of the multi-method, the types on this arguments is used to called the best method.

Returns:

the result of the called of the best method.

Throws:

NoMatchingMethodException - there is no method that match the parameter arguments.

MultipleMatchingMethodsException - there is no method that match the parameter arguments.

java.lang.reflect.InvocationTargetException - if the best method called raise an exception during its execution, this exception is wrapped into the InvocationTargetException.

java.lang.IllegalAccessException - if best method isn't accessible.

See Also:

java.lang.reflect.Method.invoke, invoke(Object, Object[])

invoke

public java.lang.Object invoke(java.lang.Object target,
                               java.lang.Object[] args,
                               java.lang.Class[] types)
                        throws java.lang.IllegalAccessException,
                               java.lang.reflect.InvocationTargetException,
                               NoMatchingMethodException,
                               MultipleMatchingMethodsException

call the best method of the multi-method according to the type of all items if args array on a specified target object.

Parameters:

target - object on which the best method is called.

args - arguments of the multi-method,

types - the best method of the multi-method is called according to this types.

Returns:

the result of the called of the best method.

Throws:

NoMatchingMethodException - there is no method that match the parameter types.

MultipleMatchingMethodsException - there is no method that match the parameter types.

java.lang.reflect.InvocationTargetException - if the best method called raise an exception during its execution, this exception is wrapped into the InvocationTargetException.

java.lang.IllegalAccessException - if best method isn't accessible.

See Also:

java.lang.reflect.Method.invoke

getModifiers

public int getModifiers()

returns the Java language modifiers for the multi-method represented by this MultiMethod object, as an integer. The Modifier class should be used to decode the modifiers.

Specified by:

getModifiers in interface java.lang.reflect.Member

See Also:

Modifier

getName

public java.lang.String getName()

return the name of the current multi-method.

Specified by:

getName in interface java.lang.reflect.Member

getDeclaringClass

public java.lang.Class getDeclaringClass()

return class that contains all methods of the current multi-method.

Specified by:

getDeclaringClass in interface java.lang.reflect.Member

getParameterTypes

public java.lang.Class[] getParameterTypes()

return the parameter types of the current method. a parameter type is the lowest common subtype of all parameter types of the methods that composed the multi-method.

Returns:

an array of class that contains all parameter types of the current multi-method.

See Also:

java.lang.reflect.Method.getParameterTypes

getExceptionTypes

public java.lang.Class[] getExceptionTypes()

return the exception types of the current method. The exception types is the union of all exception types of all methods.

Returns:

an array of class that contains all exception types of the current multi-method.

See Also:

java.lang.reflect.Method.getExceptionTypes

getReturnType

public java.lang.Class getReturnType()

return the return type of the current method. a return type is the lowest common subtype of all return types of the methods that composed the multi-method.

Returns:

a class that contains the return type of the current multi-method.

See Also:

java.lang.reflect.Method.getReturnType

asMethod

public java.lang.reflect.Method asMethod()

return a Java Method object that corresponding to the current multi-method. this method is dynamically generated. THIS METHOD ISN'T FULLY IMPLEMENTED !!!

asMethod

public java.lang.reflect.Method asMethod(java.lang.ClassLoader loader)

return a Java Method object that corresponding to the current multi-method. this method is dynamically generated. THIS METHOD ISN'T FULLY IMPLEMENTED !!!

Parameters:

loader - classloader used to load the class that contains the method.

create

public static MultiMethod create(java.lang.Class clazz,
                                 java.lang.String name,
                                 int argLength)

construct a multi-method by taking all method named name with argLength parameter(s) in class clazz.

Parameters:

clazz - class which owns the named methods.

name - name of the methods.

argLenth - number of parameters.

Throws:

java.lang.IllegalArgumentException - if the class clazz contains no method named name or all methods found don't have the same number of parameters.

create

public static MultiMethod create(java.lang.Class clazz,
                                 java.lang.String name,
                                 int argLength,
                                 boolean onlyPublic)

construct a multi-method by taking all method named name with argLength parameter(s) in class clazz.

Parameters:

clazz - class which owns the named methods.

name - name of the methods.

argLenth - number of parameters.

Throws:

java.lang.IllegalArgumentException - if the class clazz contains no method named name or all methods found don't have the same number of parameters.