de.ipcon.tools

Class ReflectionTools

java.lang.Object

de.ipcon.tools.ReflectionTools

public final class ReflectionTools
extends java.lang.Object

Field Summary

Fields

Modifier and Type	Field and Description
static org.apache.log4j.Logger	log
static sun.misc.Unsafe	unsafe Holds the Unsafe instance obtained using the getUnsafe() method.

Method Summary

Modifier and Type	Method and Description
static java.lang.Object	atomicGetAndSetObject(java.lang.Object o, java.lang.String fieldName, java.lang.Object newValue) Uses the Unsafe API to atomically initialize a field to the given value, returning the previous value.
static java.lang.Class	findNextClosestSuperClass(java.lang.Class clazz, java.util.Set<java.lang.Class> potentialSuperClazzes) finds and returns the next closes superclass for a class from a given set of potential super classes
static java.lang.Class	forceInit(java.lang.Class clazz) Loads the passed Class and initializes it.
static java.lang.Class[]	getAllInterfaces(java.lang.Class c) Returns an Array with all interfaces implemented by the given Class and its parents just a wrapper for getAllInterfaces(c = Class, set = Set)
static java.lang.Class	getClass(java.lang.String cname) Convenience version of the standard Java API method which only throws (unchecked) RuntimeExceptions.
static java.lang.Class	getClass(java.lang.String cname, java.lang.String exceptionText)
static java.lang.reflect.Constructor	getConstructor(java.lang.Class clazz) Convenience version of the standard Java API method which only throws (unchecked) RuntimeExceptions.
static java.lang.reflect.Constructor	getConstructor(java.lang.Class clazz, java.lang.Class[] types)
static java.lang.reflect.Constructor	getConstructor(java.lang.Class clazz, java.lang.Class[] types, java.lang.String exceptionText)
static int	getDistanceToJavaLangObject(java.lang.Class aClass) Computes the distance of a given class from the java.lang.Object class in its inheritance hierarchy.
static int	getDistanceToSuperClass(java.lang.Class clazz, java.lang.Class superClazz) Computes the distance of a given class from the given super class in its inheritance hierarchy.
static java.lang.Object	getField(java.lang.Class clazz, java.lang.String fname, java.lang.Object o) Returns the content of the field with the specified name for the passed class in the passed Object.
static java.lang.Object	getField(java.lang.Class clazz, java.lang.String fname, java.lang.Object o, boolean force)
static java.lang.Object	getField(java.lang.Class clazz, java.lang.String fname, java.lang.Object o, boolean force, java.lang.String exceptionText)
static long	getFieldOffset(java.lang.Class cl, java.lang.String name) Returns the offset of the field with the specified name for the passed class.
static long	getFieldOffset(java.lang.Class cl, java.lang.String name, boolean nothrow)
static java.lang.reflect.Method	getMethod(java.lang.Class clazz, java.lang.String mname) Convenience version of the standard Java API method which only throws (unchecked) RuntimeExceptions.
static java.lang.reflect.Method	getMethod(java.lang.Class clazz, java.lang.String mname, java.lang.Class[] types)
static java.lang.reflect.Method	getMethod(java.lang.Class clazz, java.lang.String mname, java.lang.Class[] types, boolean force)
static java.lang.reflect.Method	getMethod(java.lang.Class clazz, java.lang.String mname, java.lang.Class[] types, boolean force, java.lang.String exceptionText)
static java.lang.reflect.Method	getMethod(java.lang.Object o, java.lang.String mname) Convenience version of the standard Java API method which only throws (unchecked) RuntimeExceptions.
static java.lang.reflect.Method	getMethod(java.lang.Object o, java.lang.String mname, java.lang.Class[] types)
static java.lang.reflect.Method	getMethod(java.lang.Object o, java.lang.String mname, java.lang.Class[] types, boolean force)
static java.lang.reflect.Method	getMethod(java.lang.Object o, java.lang.String mname, java.lang.Class[] types, boolean force, java.lang.String exceptionText)
static java.util.List	getMethodsAnnotatedWith(java.lang.Class clazz, java.lang.Class annotation) Return all methods for a passed class, that were annotated with the respective annotation class.
static java.util.List	getMethodsAnnotatedWith(java.lang.Class clazz, java.lang.Class annotation, boolean traverseClassHierarchy)
static java.util.List	getMethodsAnnotatedWith(java.lang.Object o, java.lang.Class annotation) Return all methods for the class of the passed object, that were annotated with the respective annotation class.
static java.util.List	getMethodsAnnotatedWith(java.lang.Object o, java.lang.Class annotation, boolean traverseClassHierarchy)
static java.lang.Object	getStaticField(java.lang.Class clazz, java.lang.String fname) Returns the value of the static field with the specified name for the passed class.
static java.lang.Object	getStaticField(java.lang.Class clazz, java.lang.String fname, boolean force)
static java.lang.Object	getStaticField(java.lang.Class clazz, java.lang.String fname, boolean force, java.lang.String exceptionText)
static java.lang.Object	invoke(java.lang.reflect.Method m, java.lang.Object o) Invokes the specified method on the given object with the provided parameters.
static java.lang.Object	invoke(java.lang.reflect.Method m, java.lang.Object o, java.lang.Object[] parms)
static java.lang.Object	invoke(java.lang.reflect.Method m, java.lang.Object o, java.lang.Object[] parms, java.lang.String exceptionText)
static java.lang.Object	invoke(java.lang.Object lso, java.lang.String methodName) Invokes the specified method on the given object with the provided parameters.
static java.lang.Object	invoke(java.lang.Object lso, java.lang.String methodName, java.lang.Class[] types)
static java.lang.Object	invoke(java.lang.Object lso, java.lang.String methodName, java.lang.Class[] types, java.lang.Object[] parms)
static java.lang.Object	invokeStatic(java.lang.Class clazz, java.lang.String methodName) Invokes the specified static method on the given class with the provided parameters.
static java.lang.Object	invokeStatic(java.lang.Class clazz, java.lang.String methodName, java.lang.Class[] types)
static java.lang.Object	invokeStatic(java.lang.Class clazz, java.lang.String methodName, java.lang.Class[] types, java.lang.Object[] parms)
static boolean	isAssignableFromAny(java.lang.Class needle, java.util.Collection<java.lang.Class> classes) Returns true if the passed class is assignable from any of the classes in the passed collection.
static java.lang.Object	newInstance(java.lang.Class clazz) Creates a new instance of the specified class using the provided parameter types and parameters.
static java.lang.Object	newInstance(java.lang.Class clazz, java.lang.Class[] types)
static java.lang.Object	newInstance(java.lang.Class clazz, java.lang.Class[] types, java.lang.Object[] parms)
static java.lang.Object	newInstance(java.lang.Class clazz, java.lang.Class[] types, java.lang.Object[] parms, java.lang.String exceptionText)
static java.lang.Object	newInstance(java.lang.reflect.Constructor c) Creates a new object using the provided constructor and parameters.
static java.lang.Object	newInstance(java.lang.reflect.Constructor c, java.lang.Object[] parms)
static java.lang.Object	newInstance(java.lang.reflect.Constructor c, java.lang.Object[] parms, java.lang.String exceptionText)
static java.lang.Object	newInstance(java.lang.String cname) Creates a new instance of the specified class name using the provided parameter types and parameters.
static java.lang.Object	newInstance(java.lang.String cname, java.lang.Class[] types)
static java.lang.Object	newInstance(java.lang.String cname, java.lang.Class[] types, java.lang.Object[] parms)
static java.lang.Object	newInstance(java.lang.String cname, java.lang.Class[] types, java.lang.Object[] parms, java.lang.String exceptionText)
static void	setField(java.lang.Class clazz, java.lang.String fname, java.lang.Object o, java.lang.Object value) Sets the value of the field with the specified name for the passed class in the passed Object.
static void	setField(java.lang.Class clazz, java.lang.String fname, java.lang.Object o, java.lang.Object value, boolean force)
static void	setField(java.lang.Class clazz, java.lang.String fname, java.lang.Object o, java.lang.Object value, boolean force, java.lang.String exceptionText)

Methods inherited from class java.lang.Object

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

Field Detail

log

public static final org.apache.log4j.Logger log

unsafe

public static final sun.misc.Unsafe unsafe

Holds the Unsafe instance obtained using the getUnsafe() method.

Method Detail

isAssignableFromAny

public static boolean isAssignableFromAny(java.lang.Class needle,
                                          java.util.Collection<java.lang.Class> classes)

Returns true if the passed class is assignable from any of the classes in the passed collection.

Parameters:

needle - The Class to check assignability.

classes - The Collection of classes to check against.

Returns:

True if the class is assignable from any class in the collection, otherwise false.

getClass

public static java.lang.Class getClass(java.lang.String cname)

Convenience version of the standard Java API method which only throws (unchecked) RuntimeExceptions.

Parameters:

cname - The name of the class.

exceptionText - The exception text to include in the RuntimeException (optional).

Returns:

The Class object.

getClass

public static java.lang.Class getClass(java.lang.String cname,
                                       java.lang.String exceptionText)

getConstructor

public static java.lang.reflect.Constructor getConstructor(java.lang.Class clazz)

Convenience version of the standard Java API method which only throws (unchecked) RuntimeExceptions.

Parameters:

clazz - The Class object.

types - The parameter types.

exceptionText - The exception text to include in the RuntimeException (optional).

Returns:

The Constructor object.

getConstructor

public static java.lang.reflect.Constructor getConstructor(java.lang.Class clazz,
                                                           java.lang.Class[] types)

getConstructor

public static java.lang.reflect.Constructor getConstructor(java.lang.Class clazz,
                                                           java.lang.Class[] types,
                                                           java.lang.String exceptionText)

getMethod

public static java.lang.reflect.Method getMethod(java.lang.Class clazz,
                                                 java.lang.String mname)

Convenience version of the standard Java API method which only throws (unchecked) RuntimeExceptions.

Parameters:

clazz - The Class object.

mname - The name of the method.

types - The parameter types.

force - If true, the method is forced accessible.

exceptionText - The exception text to include in the RuntimeException (optional).

Returns:

The Method object.

getMethod

public static java.lang.reflect.Method getMethod(java.lang.Class clazz,
                                                 java.lang.String mname,
                                                 java.lang.Class[] types)

getMethod

public static java.lang.reflect.Method getMethod(java.lang.Class clazz,
                                                 java.lang.String mname,
                                                 java.lang.Class[] types,
                                                 boolean force)

getMethod

public static java.lang.reflect.Method getMethod(java.lang.Class clazz,
                                                 java.lang.String mname,
                                                 java.lang.Class[] types,
                                                 boolean force,
                                                 java.lang.String exceptionText)

getMethod

public static java.lang.reflect.Method getMethod(java.lang.Object o,
                                                 java.lang.String mname)

Convenience version of the standard Java API method which only throws (unchecked) RuntimeExceptions.

Parameters:

o - The object instance.

mname - The name of the method.

types - The parameter types.

force - If true, the method is forced accessible.

exceptionText - The exception text to include in the RuntimeException (optional).

Returns:

The Method object.

getMethod

public static java.lang.reflect.Method getMethod(java.lang.Object o,
                                                 java.lang.String mname,
                                                 java.lang.Class[] types)

getMethod

public static java.lang.reflect.Method getMethod(java.lang.Object o,
                                                 java.lang.String mname,
                                                 java.lang.Class[] types,
                                                 boolean force)

getMethod

public static java.lang.reflect.Method getMethod(java.lang.Object o,
                                                 java.lang.String mname,
                                                 java.lang.Class[] types,
                                                 boolean force,
                                                 java.lang.String exceptionText)

getMethodsAnnotatedWith

public static java.util.List getMethodsAnnotatedWith(java.lang.Class clazz,
                                                     java.lang.Class annotation)

Return all methods for a passed class, that were annotated with the respective annotation class.

Parameters:

clazz - The class that will be checked for methods.

annotation - The annotation class. If a method has the respective annotation it is returned.

traverseClassHierarchy - If true, work your way up the class hierarchy an check all classes for the respective annotation. If false, only check the passed class.

Returns:

all methods for a passed class, that were annotated with the respective annotation class.

getMethodsAnnotatedWith

public static java.util.List getMethodsAnnotatedWith(java.lang.Class clazz,
                                                     java.lang.Class annotation,
                                                     boolean traverseClassHierarchy)

getMethodsAnnotatedWith

public static java.util.List getMethodsAnnotatedWith(java.lang.Object o,
                                                     java.lang.Class annotation)

Return all methods for the class of the passed object, that were annotated with the respective annotation class.

Parameters:

o - The object to get the class of, that will be checked for methods.

annotation - The annotation class. If a method has the respective annotation it is returned.

traverseClassHierarchy - If true, work your way up the class hierarchy an check all classes for the respective annotation. If false, only check the passed class.

Returns:

all methods for the class of the passed object, that were annotated with the respective annotation class.

getMethodsAnnotatedWith

public static java.util.List getMethodsAnnotatedWith(java.lang.Object o,
                                                     java.lang.Class annotation,
                                                     boolean traverseClassHierarchy)

getField

public static java.lang.Object getField(java.lang.Class clazz,
                                        java.lang.String fname,
                                        java.lang.Object o)

Returns the content of the field with the specified name for the passed class in the passed Object. If the field is static, the passed Object is not used and may be null. The parameter force is false by default. If force is passed as true, only the declared fields are searched. Fields from interfaces or super-classes will thus not be found, but we will be able to access private and protected properties that way.

Parameters:

clazz - The Class object.

fname - The name of the field.

o - The object instance (can be null for static fields).

force - If true, only declared fields are searched.

exceptionText - The exception text to include in the RuntimeException (optional).

Returns:

The content of the field.

getField

public static java.lang.Object getField(java.lang.Class clazz,
                                        java.lang.String fname,
                                        java.lang.Object o,
                                        boolean force)

getField

public static java.lang.Object getField(java.lang.Class clazz,
                                        java.lang.String fname,
                                        java.lang.Object o,
                                        boolean force,
                                        java.lang.String exceptionText)

setField

public static void setField(java.lang.Class clazz,
                            java.lang.String fname,
                            java.lang.Object o,
                            java.lang.Object value)

Sets the value of the field with the specified name for the passed class in the passed Object. If the field is static, the passed Object is not used and may be null. The parameter force is true by default, allowing the modification of final fields. If force is passed as false, only the declared fields are modified. Fields from interfaces or super-classes will not be modified in this case.

Parameters:

clazz - The Class object.

fname - The name of the field.

o - The object instance (can be null for static fields).

value - The value to set.

force - If true, modification of final fields is allowed. If false, only declared fields are modified.

exceptionText - The exception text to include in the RuntimeException (optional).

setField

public static void setField(java.lang.Class clazz,
                            java.lang.String fname,
                            java.lang.Object o,
                            java.lang.Object value,
                            boolean force)

setField

public static void setField(java.lang.Class clazz,
                            java.lang.String fname,
                            java.lang.Object o,
                            java.lang.Object value,
                            boolean force,
                            java.lang.String exceptionText)

getStaticField

public static java.lang.Object getStaticField(java.lang.Class clazz,
                                              java.lang.String fname)

Returns the value of the static field with the specified name for the passed class. The parameter force is true by default, allowing the retrieval of values from final fields. If force is passed as false, only declared fields are accessed.

Parameters:

clazz - The Class object.

fname - The name of the field.

force - If true, access to final fields is allowed. If false, only declared fields are accessed.

exceptionText - The exception text to include in the RuntimeException (optional).

Returns:

The value of the static field.

getStaticField

public static java.lang.Object getStaticField(java.lang.Class clazz,
                                              java.lang.String fname,
                                              boolean force)

getStaticField

public static java.lang.Object getStaticField(java.lang.Class clazz,
                                              java.lang.String fname,
                                              boolean force,
                                              java.lang.String exceptionText)

getFieldOffset

public static long getFieldOffset(java.lang.Class cl,
                                  java.lang.String name)

Returns the offset of the field with the specified name for the passed class.

Parameters:

cl - The Class object.

name - The name of the field.

nothrow - If true, no exception is thrown if the field is not found.

Returns:

The offset of the field.

getFieldOffset

public static long getFieldOffset(java.lang.Class cl,
                                  java.lang.String name,
                                  boolean nothrow)

atomicGetAndSetObject

public static java.lang.Object atomicGetAndSetObject(java.lang.Object o,
                                                     java.lang.String fieldName,
                                                     java.lang.Object newValue)

Uses the Unsafe API to atomically initialize a field to the given value, returning the previous value.

Parameters:

o - object/array to update the field/element in

fieldName - name of the field to be set

newValue - new value

Returns:

the previous value

newInstance

public static java.lang.Object newInstance(java.lang.reflect.Constructor c)

Creates a new object using the provided constructor and parameters.

Parameters:

c - The Constructor object.

parms - The parameters for the constructor.

exceptionText - The exception text to include in the RuntimeException (optional).

Returns:

The new instance of the class.

newInstance

public static java.lang.Object newInstance(java.lang.reflect.Constructor c,
                                           java.lang.Object[] parms)

newInstance

public static java.lang.Object newInstance(java.lang.reflect.Constructor c,
                                           java.lang.Object[] parms,
                                           java.lang.String exceptionText)

newInstance

public static java.lang.Object newInstance(java.lang.String cname)

Creates a new instance of the specified class name using the provided parameter types and parameters.

Parameters:

cname - The name of the class.

types - The parameter types for the constructor.

parms - The parameters for the constructor.

exceptionText - The exception text to include in the RuntimeException (optional).

Returns:

The new instance of the class.

newInstance

public static java.lang.Object newInstance(java.lang.String cname,
                                           java.lang.Class[] types)

newInstance

public static java.lang.Object newInstance(java.lang.String cname,
                                           java.lang.Class[] types,
                                           java.lang.Object[] parms)

newInstance

public static java.lang.Object newInstance(java.lang.String cname,
                                           java.lang.Class[] types,
                                           java.lang.Object[] parms,
                                           java.lang.String exceptionText)

newInstance

public static java.lang.Object newInstance(java.lang.Class clazz)

Creates a new instance of the specified class using the provided parameter types and parameters.

Parameters:

clazz - The Class object.

types - The parameter types for the constructor.

parms - The parameters for the constructor.

exceptionText - The exception text to include in the RuntimeException (optional).

Returns:

The new instance of the class.

newInstance

public static java.lang.Object newInstance(java.lang.Class clazz,
                                           java.lang.Class[] types)

newInstance

public static java.lang.Object newInstance(java.lang.Class clazz,
                                           java.lang.Class[] types,
                                           java.lang.Object[] parms)

newInstance

public static java.lang.Object newInstance(java.lang.Class clazz,
                                           java.lang.Class[] types,
                                           java.lang.Object[] parms,
                                           java.lang.String exceptionText)

invoke

public static java.lang.Object invoke(java.lang.reflect.Method m,
                                      java.lang.Object o)

Invokes the specified method on the given object with the provided parameters.

Parameters:

m - The Method object.

o - The object on which to invoke the method.

parms - The parameters for the method.

exceptionText - The exception text to include in the RuntimeException (optional).

Returns:

The result of the method invocation.

invoke

public static java.lang.Object invoke(java.lang.reflect.Method m,
                                      java.lang.Object o,
                                      java.lang.Object[] parms)

invoke

public static java.lang.Object invoke(java.lang.reflect.Method m,
                                      java.lang.Object o,
                                      java.lang.Object[] parms,
                                      java.lang.String exceptionText)

invoke

public static java.lang.Object invoke(java.lang.Object lso,
                                      java.lang.String methodName)

Invokes the specified method on the given object with the provided parameters.

Parameters:

lso - The object on which to invoke the method.

methodName - The name of the method.

types - The parameter types for the method.

parms - The parameters for the method.

Returns:

The result of the method invocation.

invoke

public static java.lang.Object invoke(java.lang.Object lso,
                                      java.lang.String methodName,
                                      java.lang.Class[] types)

invoke

public static java.lang.Object invoke(java.lang.Object lso,
                                      java.lang.String methodName,
                                      java.lang.Class[] types,
                                      java.lang.Object[] parms)

invokeStatic

public static java.lang.Object invokeStatic(java.lang.Class clazz,
                                            java.lang.String methodName)

Invokes the specified static method on the given class with the provided parameters.

Parameters:

clazz - The Class object.

methodName - The name of the method.

types - The parameter types for the method.

parms - The parameters for the method.

Returns:

The result of the method invocation.

invokeStatic

public static java.lang.Object invokeStatic(java.lang.Class clazz,
                                            java.lang.String methodName,
                                            java.lang.Class[] types)

invokeStatic

public static java.lang.Object invokeStatic(java.lang.Class clazz,
                                            java.lang.String methodName,
                                            java.lang.Class[] types,
                                            java.lang.Object[] parms)

forceInit

public static java.lang.Class forceInit(java.lang.Class clazz)

Loads the passed Class and initializes it.

Parameters:

clazz - The Class object to force initialization of.

Returns:

The initialized Class object.

getAllInterfaces

public static java.lang.Class[] getAllInterfaces(java.lang.Class c)

Returns an Array with all interfaces implemented by the given Class and its parents just a wrapper for getAllInterfaces(c = Class, set = Set)

Parameters:

c - the Class to get the interfaces for

Returns:

an array with all implemented interfaces

getDistanceToJavaLangObject

public static int getDistanceToJavaLangObject(java.lang.Class aClass)

Computes the distance of a given class from the java.lang.Object class in its inheritance hierarchy.

The method traverses the inheritance chain of the specified class, counting the number of steps required to reach the java.lang.Object class. The distance is defined as the number of superclass links from the given class to java.lang.Object. The method returns the count of these steps.

For example, if the specified class directly extends java.lang.Object, the distance will be 1. If the specified class extends another class which in turn extends java.lang.Object, the distance will be 2, and so on.

Parameters:

aClass - the class for which the distance to java.lang.Object is to be calculated. If null is passed, the method returns 0.

Returns:

the number of superclasses between the specified class and java.lang.Object.

getDistanceToSuperClass

public static int getDistanceToSuperClass(java.lang.Class clazz,
                                          java.lang.Class superClazz)

Computes the distance of a given class from the given super class in its inheritance hierarchy.

The method traverses the inheritance chain of the specified class, counting the number of steps required to reach the given super class. The distance is defined as the number of superclass links from the given class to the given super class. The method returns the count of these steps. If the provided class and super class are unrelated, -1 is returned.

For example, if the specified class directly extends the super class, the distance will be 1. If the specified class extends another class which in turn extends the super class, the distance will be 2, and so on.

Parameters:

clazz - the class for which the distance to the given super class is to be calculated. If null is passed, the method returns 0. If the given class and super class are unrelated, the method returns -1.

superClazz - the super clazz to use as an upper boundary for the calculation of steps.

Returns:

the number of superclasses between the specified class and the specified super class, or 0 if clazz is null, or -1 if both classes are unrelated.

findNextClosestSuperClass

public static java.lang.Class findNextClosestSuperClass(java.lang.Class clazz,
                                                        java.util.Set<java.lang.Class> potentialSuperClazzes)

finds and returns the next closes superclass for a class from a given set of potential super classes

Parameters:

clazz -

potentialSuperClazzes -

Returns:

the closest super class of clazz that was present in the list of potentialSuperClazzes. If none of the potentialSuperClazzes are actual super classes of clazz, null is returned.