org.apache.openjpa.lib.util
Class ConcreteClassGenerator

java.lang.Object
  org.apache.openjpa.lib.util.ConcreteClassGenerator

public class ConcreteClassGenerator
extends Object

Dynamically generates concrete implementations of abstract classes.

Since:

1.3.0

Author:

Marc Prud'hommeaux, Pinaki Poddar

Constructor Summary

ConcreteClassGenerator()

Method Summary

static <T> Constructor<T>	getConcreteConstructor(Class<T> abstractClass, Class<?>... argTypes) Get the constructor of the concrete, dynamic wrapper class of the given abstract class with matching argument types.
static <T> Class<? extends T>	makeConcrete(Class<T> abstractClass) Takes an abstract class and returns a concrete implementation.
static <T> T	newInstance(Class<T> c)
static <T> T	newInstance(Class<T> c, Class<?>[] paramTypes, Object[] params) Utility method for safely invoking a constructor that we do not expect to throw exceptions.
static <T,P> T	newInstance(Class<T> c, Class<? extends P> paramType, P param)
static <T,P1,P2> T	newInstance(Class<T> c, Class<? extends P1> paramType1, P1 param1, Class<? extends P2> paramType2, P2 param2)
static <T,P1,P2,P3> T	newInstance(Class<T> c, Class<? extends P1> paramType1, P1 param1, Class<? extends P2> paramType2, P2 param2, Class<? extends P3> paramType3, P3 param3)
static <T,P1,P2,P3,P4> T	newInstance(Class<T> c, Class<? extends P1> paramType1, P1 param1, Class<? extends P2> paramType2, P2 param2, Class<? extends P3> paramType3, P3 param3, Class<? extends P4> paramType4, P4 param4)
static <T> T	newInstance(Constructor<T> cons, Object... params) Construct a new instance by the given constructor and its arguments.

Methods inherited from class java.lang.Object

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

Constructor Detail

ConcreteClassGenerator

public ConcreteClassGenerator()

Method Detail

getConcreteConstructor

public static <T> Constructor<T> getConcreteConstructor(Class<T> abstractClass,
                                                        Class<?>... argTypes)
                                             throws ClassNotFoundException

Get the constructor of the concrete, dynamic wrapper class of the given abstract class with matching argument types.

Parameters:

the - argTypes of the constructor to look for. null signify default constructor.

Throws:

ClassNotFoundException

makeConcrete

public static <T> Class<? extends T> makeConcrete(Class<T> abstractClass)
                                       throws ClassNotFoundException

Takes an abstract class and returns a concrete implementation. Note that it doesn't actually implement any abstract methods, it merely makes an abstract class loadable. Abstract methods will throw a AbstractMethodError.

Parameters:

abstractClass - the abstract class

Returns:

a concrete class

Throws:

ClassNotFoundException

newInstance

public static <T> T newInstance(Constructor<T> cons,
                                Object... params)

Construct a new instance by the given constructor and its arguments. Hopefully faster than looking for constructor in overloaded implementations.

newInstance

public static <T> T newInstance(Class<T> c,
                                Class<?>[] paramTypes,
                                Object[] params)

Utility method for safely invoking a constructor that we do not expect to throw exceptions.

Parameters:

c - the class to construct

paramTypes - the types of the parameters

params - the parameter values

Returns:

the new instance

newInstance

public static <T> T newInstance(Class<T> c)

See Also:

newInstance(java.lang.Class,java.lang.Class[],java.lang.Object[])

newInstance

public static <T,P> T newInstance(Class<T> c,
                                  Class<? extends P> paramType,
                                  P param)

See Also:

newInstance(java.lang.Class,java.lang.Class[],java.lang.Object[])

newInstance

public static <T,P1,P2> T newInstance(Class<T> c,
                                      Class<? extends P1> paramType1,
                                      P1 param1,
                                      Class<? extends P2> paramType2,
                                      P2 param2)

See Also:

newInstance(java.lang.Class,java.lang.Class[],java.lang.Object[])

newInstance

public static <T,P1,P2,P3> T newInstance(Class<T> c,
                                         Class<? extends P1> paramType1,
                                         P1 param1,
                                         Class<? extends P2> paramType2,
                                         P2 param2,
                                         Class<? extends P3> paramType3,
                                         P3 param3)

See Also:

newInstance(java.lang.Class,java.lang.Class[],java.lang.Object[])

newInstance

public static <T,P1,P2,P3,P4> T newInstance(Class<T> c,
                                            Class<? extends P1> paramType1,
                                            P1 param1,
                                            Class<? extends P2> paramType2,
                                            P2 param2,
                                            Class<? extends P3> paramType3,
                                            P3 param3,
                                            Class<? extends P4> paramType4,
                                            P4 param4)

See Also:

newInstance(java.lang.Class,java.lang.Class[],java.lang.Object[])