com.knowgate.typeutils

Class ObjectFactory

java.lang.Object

com.knowgate.typeutils.ObjectFactory

public class ObjectFactory
extends Object

Base class with helper methods for object instantiation using reflection.

Version:

1.0

Author:

Sergio Montoro Ten

Constructor Summary

Constructors

Constructor and Description
ObjectFactory()

Method Summary

Modifier and Type	Method and Description
static Object[]	filterParameters(Parameter[] parameters, Object[] parameterValues) Filter parameter values that has the necessary types.
static Class<?>[]	getClassTree(Class<?> clss) Get super classes and interfaces implemented by the given class
static Constructor<? extends Object>	getConstructor(Class<? extends Object> objectClass, Class<?>[] parameterClasses) Get the constructor for a class that matches the given parameter classes.
protected static Class<?>[]	getParameterClasses(Object... constructorParameters) Get an array with the classes of the given parameters
protected static Set<Class<?>>	getSubclassesOf(Package pkg, Class<?> superClass)
static String	signature(Class<? extends Object> objectClass, Class<?>[] parameterClasses) Generate a String which represent the signature of the given classes.
protected static Constructor<? extends Object>	tryConstructor(Class<? extends Object> objectClass, Class<?>... parameterClasses)

Methods inherited from class java.lang.Object

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

Constructor Detail

ObjectFactory

public ObjectFactory()

Method Detail

getConstructor

public static Constructor<? extends Object> getConstructor(Class<? extends Object> objectClass,
                                                           Class<?>[] parameterClasses)
                                                    throws IllegalArgumentException

Get the constructor for a class that matches the given parameter classes.

Parameters:

objectClass - Class<? extends Object>

parameterClasses - Class<?>[]

Returns:

Constructor<? extends Object> or null if there is no constructor with given parameters at the class.

Throws:

IllegalArgumentException - If more than one constructor is suitable for the given arguments but its signature does not exactly match the classes of the parameters

filterParameters

public static Object[] filterParameters(Parameter[] parameters,
                                        Object[] parameterValues)
                                 throws InstantiationException

Filter parameter values that has the necessary types.

Case 1. If parameters.length is equal to parameterValues.length then the types of parameterValues will be checked to match the ones specified at parameters. If the types do not match then InstantiationException will be thrown. If the types match then parameterValues will be returned.

Case 2. If parameters.length is less than parameterValues.length then the first n parameter values with the same types as parameters will be returned.

Case 3. If parameters.length is greater than parameterValues.length then InstantiationException will be thrown.

Parameters:

parameters - Parameter[]

parameterValues - Object[]

Returns:

Object[]

Throws:

InstantiationException

getParameterClasses

protected static Class<?>[] getParameterClasses(Object... constructorParameters)

Get an array with the classes of the given parameters

Parameters:

constructorParameters - Object…

Returns:

static Class<?>[]

signature

public static String signature(Class<? extends Object> objectClass,
                               Class<?>[] parameterClasses)

Generate a String which represent the signature of the given classes. The signature is generated by concatenating the class names.

Parameters:

objectClass - Class<? extends Object>

parameterClasses - Class<?>[]

Returns:

String

getClassTree

public static Class<?>[] getClassTree(Class<?> clss)

Get super classes and interfaces implemented by the given class

Parameters:

clss - Class<?>

Returns:

Class<?>[] Super classes followed by interfaces (including interfaces implemented by super classes)

tryConstructor

protected static Constructor<? extends Object> tryConstructor(Class<? extends Object> objectClass,
                                                              Class<?>... parameterClasses)

getSubclassesOf

protected static Set<Class<?>> getSubclassesOf(Package pkg,
                                               Class<?> superClass)
                                        throws RuntimeException

Throws:

RuntimeException