de.bea.domingo.map
Class ClassUtilities

java.lang.Object
  de.bea.domingo.map.ClassUtilities

final class ClassUtilities
extends java.lang.Object

Utility methods for querying Class objects.

Method Summary

static java.lang.Class	classForNameOrPrimitive(java.lang.String name, java.lang.ClassLoader loader)
static boolean	classIsAccessible(java.lang.Class aClass)
static boolean	compatibleClasses(java.lang.Class[] lhs, java.lang.Class[] rhs) Tells whether instances of the classes in the 'rhs' array could be used as parameters to a reflective method invocation whose parameter list has types denoted by the 'lhs' array.
static java.lang.reflect.Method	getAccessibleMethodFrom(java.lang.Class aClass, java.lang.String methodName, java.lang.Class[] parameterTypes)
static java.lang.Class	primitiveEquivalentOf(java.lang.Class aClass)
static boolean	primitiveIsAssignableFrom(java.lang.Class lhs, java.lang.Class rhs) Tells whether an instance of the primitive class represented by 'rhs' can be assigned to an instance of the primitive class represented by 'lhs'.

Methods inherited from class java.lang.Object

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

Method Detail

classForNameOrPrimitive

public static java.lang.Class classForNameOrPrimitive(java.lang.String name,
                                                      java.lang.ClassLoader loader)
                                               throws java.lang.ClassNotFoundException

Parameters:

name - FQN of a class, or the name of a primitive type

loader - a ClassLoader

Returns:

the Class for the name given. Primitive types are converted to their particular Class object. null, the empty string, "null", and "void" yield Void.TYPE. If any classes require loading because of this operation, the loading is done by the given class loader. Such classes are not initialized, however.

Throws:

java.lang.ClassNotFoundException - if name names an unknown class or primitive

classIsAccessible

public static boolean classIsAccessible(java.lang.Class aClass)

Parameters:

aClass - a Class

Returns:

true if the class is accessible, false otherwise. Presently returns true if the class is declared public.

compatibleClasses

public static boolean compatibleClasses(java.lang.Class[] lhs,
                                        java.lang.Class[] rhs)

Tells whether instances of the classes in the 'rhs' array could be used as parameters to a reflective method invocation whose parameter list has types denoted by the 'lhs' array.

Parameters:

lhs - Class array representing the types of the formal parameters of a method

rhs - Class array representing the types of the actual parameters of a method. A null value or Void.TYPE is considered to match a corresponding Object or array class in lhs, but not a primitive.

Returns:

true if compatible, false otherwise

getAccessibleMethodFrom

public static java.lang.reflect.Method getAccessibleMethodFrom(java.lang.Class aClass,
                                                               java.lang.String methodName,
                                                               java.lang.Class[] parameterTypes)

Parameters:

aClass - a Class

methodName - name of a method

parameterTypes - Class array representing the types of a method's formal parameters

Returns:

the Method with the given name and formal parameter types that is in the nearest accessible class in the class hierarchy, starting with aClass's superclass. The superclass and implemented interfaces of aClass are searched, then their superclasses, etc. until a method is found. Returns null if there is no such method.

primitiveEquivalentOf

public static java.lang.Class primitiveEquivalentOf(java.lang.Class aClass)

Parameters:

aClass - a Class

Returns:

the class's primitive equivalent, if aClass is a primitive wrapper. If aClass is primitive, returns aClass. Otherwise, returns null.

primitiveIsAssignableFrom

public static boolean primitiveIsAssignableFrom(java.lang.Class lhs,
                                                java.lang.Class rhs)

Tells whether an instance of the primitive class represented by 'rhs' can be assigned to an instance of the primitive class represented by 'lhs'.

Parameters:

lhs - assignee class

rhs - assigned class

Returns:

true if compatible, false otherwise. If either argument is null, or one of the parameters does not represent a primitive (e.g. Byte.TYPE), returns false.