Package org.djunits.util

Class ClassUtil

java.lang.Object

org.djunits.util.ClassUtil

public final class ClassUtil
extends Object

ClassUtil is a utility class providing assistance for Java Classes.

Copyright (c) 2002-2009 Delft University of Technology, Jaffalaan 5, 2628 BX Delft, the Netherlands. All rights reserved.

See for project information www.getSI()mulation.tudelft.nl.

The DSOL project is distributed under the following BSD-style license:
Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:

• Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.
• Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.
• Neither the name of Delft University of Technology, nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission.

This software is provided by the copyright holders and contributors "as is" and any express or implied warranties, including, but not limited to, the implied warranties of merchantability and fitness for a particular purpose are disclaimed. In no event shall the copyright holder or contributors be liable for any direct, indirect, incidental, special, exemplary, or consequential damages (including, but not limited to, procurement of substitute goods or services; loss of use, data, or profits; or business interruption) however caused and on any theory of liability, whether in contract, strict liability, or tort (including negligence or otherwise) arising in any way out of the use of this software, even if advised of the possibility of such damage.

Since:

1.5

Version:

$Revision: 1.3 $ $Date: 2010/08/10 11:39:11 $

Author:

Peter Jacobs, Niels Lang, Alexander Verbraeck

Method Summary

Modifier and Type	Method	Description
static Constructor<?>[]	getAllConstructors(Class<?> clazz, Constructor<?>[] result)	gets all the constructors of a class and adds the result to result.
static Set<Field>	getAllFields(Class<?> clazz)	gets all the fields of a class (public, protected, package, and private).
static Set<Field>	getAllFields(Class<?> clazz, Set<Field> result)	gets all the fields of a class (public, protected, package, and private) and adds the result to the return value.
static Method[]	getAllMethods(Class<?> clazz, String name, Method[] result)	gets all the methods of a class and adds the result to result.
static Class<?>[]	getClass(Object[] array)	converts an array of objects to their corresponding classes.
static boolean	isMoreSpecific(Class<?>[] a, Class<?>[] b)	Determines & returns whether constructor 'a' is more specific than constructor 'b', as defined in the Java Language Specification ???
static boolean	isMoreSpecific(Constructor<?> a, Constructor<?> b)	Determines & returns whether constructor 'a' is more specific than constructor 'b', as defined in the Java Language Specification ???
static boolean	isMoreSpecific(Method a, Method b)	Determines & returns whether constructor 'a' is more specific than constructor 'b', as defined in the Java Language Specification ???
static boolean	isVisible(int modifiers, Class<?> declaringClass, Class<?> caller)	Returns whether a declaringClass is accessible according to the modifiers.
static boolean	isVisible(Constructor<?> constructor, Class<?> caller)	Returns whether a constructor is visible for a caller.
static boolean	isVisible(Field field, Class<?> caller)	Returns whether a field is visible for a caller.
static boolean	isVisible(Method method, Class<?> caller)	Returns whether a method is visible for a caller.
static Constructor<?>[]	matchSignature(Constructor<?>[] constructors, Class<?>... argTypes)	Filters an array methods for signatures that are compatible with a given signature.
static boolean	matchSignature(Constructor<?> constructor, Class<?>... argTypes)	Filters an array methods for signatures that are compatible with a given signature.
static Method[]	matchSignature(Method[] methods, String name, Class<?>... argTypes)	Filters an array methods for signatures that are compatible with a given signature.
static boolean	matchSignature(Method method, String name, Class<?>... argTypes)	Filters an array methods for signatures that are compatible with a given signature.
static Constructor<?>	resolveConstructor(Class<?> clazz, Class<?>... parameterTypes)	returns the interface method.
static Constructor<?>	resolveConstructor(Class<?> clazz, Class<?> callerClass, Class<?>... parameterTypes)	returns the interface method.
static Constructor<?>	resolveConstructor(Class<?> clazz, Object[] arguments)	returns the constructor.
static Field	resolveField(Class<?> clazz, Class<?> callerClass, String name)	returns the field.
static Field	resolveField(Class<?> clazz, String fieldName)	resolves the field for a class, taking into account inner classes.
static Field	resolveField(Object object, String fieldName)	resolves the field for a given object instance.
static Method	resolveMethod(Class<?> clazz, Class<?> callerClass, String name, Class<?>... parameterTypes)	returns the interface method.
static Method	resolveMethod(Class<?> clazz, String name, Class<?>... parameterTypes)	returns the interface method.
static Method	resolveMethod(Object object, String name, Class<?>... parameterTypes)	resolves a method the method.
static Method	resolveMethod(Object object, String name, Object[] arguments)	returns the method.

Methods inherited from class java.lang.Object

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

Method Details

getAllConstructors

public static Constructor<?>[] getAllConstructors(Class<?> clazz,
 Constructor<?>[] result)

gets all the constructors of a class and adds the result to result.

Parameters:

clazz - the class

result - the resulting set

Returns:

result

resolveConstructor

public static Constructor<?> resolveConstructor(Class<?> clazz,
 Class<?> callerClass,
 Class<?>... parameterTypes)
                                         throws NoSuchMethodException

returns the interface method.

Parameters:

clazz - the class to start with

callerClass - the calling class

parameterTypes - the parameterTypes

Returns:

Constructor

Throws:

NoSuchMethodException - if the method cannot be resolved

resolveConstructor

public static Constructor<?> resolveConstructor(Class<?> clazz,
 Class<?>... parameterTypes)
                                         throws NoSuchMethodException

returns the interface method.

Parameters:

clazz - the class to start with

parameterTypes - the parameterTypes

Returns:

Constructor

Throws:

NoSuchMethodException - if the method cannot be resolved

resolveConstructor

public static Constructor<?> resolveConstructor(Class<?> clazz,
 Object[] arguments)
                                         throws NoSuchMethodException

returns the constructor.

Parameters:

clazz - the clazz to start with

arguments - the arguments

Returns:

Constructor

Throws:

NoSuchMethodException - on lookup failure

getAllFields

public static Set<Field> getAllFields(Class<?> clazz,
 Set<Field> result)

gets all the fields of a class (public, protected, package, and private) and adds the result to the return value.

Parameters:

clazz - the class

result - the resulting set

Returns:

the set of fields including all fields of the field clazz

getAllFields

public static Set<Field> getAllFields(Class<?> clazz)

gets all the fields of a class (public, protected, package, and private).

Parameters:

clazz - the class

Returns:

all fields of the class

resolveField

public static Field resolveField(Class<?> clazz,
 String fieldName)
                          throws NoSuchFieldException

resolves the field for a class, taking into account inner classes.

Parameters:

clazz - the class to resolve the field for, including inner classes

fieldName - name of the field

Returns:

Field the field

Throws:

NoSuchFieldException - on no such field

resolveField

public static Field resolveField(Class<?> clazz,
 Class<?> callerClass,
 String name)
                          throws NoSuchFieldException

returns the field.

Parameters:

clazz - the class to start with

callerClass - the calling class

name - the fieldName

Returns:

Constructor

Throws:

NoSuchFieldException - if the method cannot be resolved

resolveField

public static Field resolveField(Object object,
 String fieldName)
                          throws NoSuchFieldException

resolves the field for a given object instance.

Parameters:

object - the object to resolve the field for

fieldName - name of the field to resolve

Returns:

the field (if found)

Throws:

NoSuchFieldException - if the field cannot be resolved

getAllMethods

public static Method[] getAllMethods(Class<?> clazz,
 String name,
 Method[] result)

gets all the methods of a class and adds the result to result.

Parameters:

clazz - the class

name - the name of the method

result - the resulting set

Returns:

result

resolveMethod

public static Method resolveMethod(Class<?> clazz,
 Class<?> callerClass,
 String name,
 Class<?>... parameterTypes)
                            throws NoSuchMethodException

returns the interface method.

Parameters:

clazz - the class to start with

callerClass - the caller class

name - the name of the method

parameterTypes - the parameterTypes

Returns:

Method

Throws:

NoSuchMethodException - on lookup failure

resolveMethod

public static Method resolveMethod(Class<?> clazz,
 String name,
 Class<?>... parameterTypes)
                            throws NoSuchMethodException

returns the interface method.

Parameters:

clazz - the class to start with

name - the name of the method

parameterTypes - the parameterTypes

Returns:

Method

Throws:

NoSuchMethodException - on lookup failure

resolveMethod

public static Method resolveMethod(Object object,
 String name,
 Class<?>... parameterTypes)
                            throws NoSuchMethodException

resolves a method the method.

Parameters:

object - the object to start with

name - the name of the method

parameterTypes - the parameterTypes

Returns:

Method

Throws:

NoSuchMethodException - on lookup failure

resolveMethod

public static Method resolveMethod(Object object,
 String name,
 Object[] arguments)
                            throws NoSuchMethodException

returns the method.

Parameters:

object - the object to start with

name - the name of the method

arguments - the arguments

Returns:

Method

Throws:

NoSuchMethodException - on lookup failure

isVisible

public static boolean isVisible(int modifiers,
 Class<?> declaringClass,
 Class<?> caller)

Returns whether a declaringClass is accessible according to the modifiers.

Parameters:

modifiers - the modifiers

declaringClass - the declaringClass

caller - the caller

Returns:

boolean isVisible

isMoreSpecific

public static boolean isMoreSpecific(Class<?>[] a,
 Class<?>[] b)

Determines & returns whether constructor 'a' is more specific than constructor 'b', as defined in the Java Language Specification ???15.12.

Parameters:

a - reflects the first constructor

b - reflects the second constructor

Returns:

true if 'a' is more specific than b, false otherwise. 'false' is also returned when constructors are incompatible, e.g. have different names or a different number of parameters.

isMoreSpecific

public static boolean isMoreSpecific(Constructor<?> a,
 Constructor<?> b)

Determines & returns whether constructor 'a' is more specific than constructor 'b', as defined in the Java Language Specification ???15.12.

Parameters:

a - reflects the first constructor

b - reflects the second constructor

Returns:

true if 'a' is more specific than b, false otherwise. 'false' is also returned when constructors are incompatible, e.g. have different names or a different number of parameters.

isMoreSpecific

public static boolean isMoreSpecific(Method a,
 Method b)

Determines & returns whether constructor 'a' is more specific than constructor 'b', as defined in the Java Language Specification ???15.12.

Parameters:

a - reflects the first method

b - reflects the second method

Returns:

true if 'a' is more specific than b, false otherwise. 'false' is also returned when constructors are incompatible, e.g. have different names or a different number of parameters.

isVisible

public static boolean isVisible(Field field,
 Class<?> caller)

Returns whether a field is visible for a caller.

Parameters:

field - The field

caller - The class of the caller for whom invocation visibility is checked.

Returns:

boolean yes or no

isVisible

public static boolean isVisible(Constructor<?> constructor,
 Class<?> caller)

Returns whether a constructor is visible for a caller.

Parameters:

constructor - The constructor

caller - The class of the caller for whom invocation visibility is checked.

Returns:

boolean yes or no

isVisible

public static boolean isVisible(Method method,
 Class<?> caller)

Returns whether a method is visible for a caller.

Parameters:

method - The method

caller - The class of the caller for whom invocation visibility is checked.

Returns:

boolean yes or no

matchSignature

public static Method[] matchSignature(Method[] methods,
 String name,
 Class<?>... argTypes)

Filters an array methods for signatures that are compatible with a given signature.

Parameters:

methods - which are methods to be filtered.

name - reflects the method's name, part of the signature

argTypes - are the method's argument types

Returns:

Method[] An unordered Method-array consisting of the elements of 'methods' that match with the given signature. An array with 0 elements is returned when no matching Method objects are found.

matchSignature

public static boolean matchSignature(Method method,
 String name,
 Class<?>... argTypes)

Filters an array methods for signatures that are compatible with a given signature.

Parameters:

method - The method to be filtered.

name - reflects the method's name, part of the signature

argTypes - are the method's argument types

Returns:

boolean if methodParameters assignable from argTypes

matchSignature

public static boolean matchSignature(Constructor<?> constructor,
 Class<?>... argTypes)

Filters an array methods for signatures that are compatible with a given signature.

Parameters:

constructor - which are constructors to be filtered.

argTypes - are the constructor's argument types

Returns:

boolean if methodParameters assignable from argTypes

matchSignature

public static Constructor<?>[] matchSignature(Constructor<?>[] constructors,
 Class<?>... argTypes)

Filters an array methods for signatures that are compatible with a given signature.

Parameters:

constructors - which are constructors to be filtered.

argTypes - are the constructor's argument types

Returns:

Constructor<?>[] An unordered Constructor-array consisting of the elements of 'constructors' that match with the given signature. An array with 0 elements is returned when no matching Method objects are found.

getClass

public static Class<?>[] getClass(Object[] array)

converts an array of objects to their corresponding classes.

Parameters:

array - the array to invoke

Returns:

Class<?>[] the result;