org.hkijena.jipipe.utils

Class ReflectionUtils

java.lang.Object

org.hkijena.jipipe.utils.ReflectionUtils

public class ReflectionUtils
extends Object

Utilities around reflection

Method Summary

Modifier and Type	Method and Description
static int	getClassDistance(Class<?> parent, Class<?> child) The number of hierarchy classes between two classes.
static Object	getDeclaredFieldValue(String fieldName, Object instance) Gets the value of a field
static Object	getDeclaredStaticFieldValue(String fieldName, Class<?> klass) Gets the value of a field
static <E extends Enum> E[]	getEnumValues(Class<?> enumClass) Gets all enum values via reflection
static Object	getFieldValue(Field field, Object instance) Gets the value of a field
static Object	getFieldValue(String fieldName, Object instance) Gets the value of a field
static Attributes	getManifestAttributes()
static Object	getStaticFieldValue(String fieldName, Class<?> klass) Gets the value of a field
static boolean	hasDefaultConstructor(Class<?> klass) Returns true if the class has a default constructor
static Object	invokeMethod(Object target, String functionName, Object... args) Calls a function and returns its output
static boolean	isAbstractOrInterface(Class<?> klass)
static boolean	isAssignableTo(Class<?> from, Class<?> to) More powerful variant of Class.isAssignableFrom that supports primitives.
static boolean	isPrimitiveWrapperOf(Class<?> targetClass, Class<?> primitive) Returns true if the class is a primitive wrapper
static Object	newInstance(Class<?> klass, Object... args) Creates a new class instance.
static void	setDeclaredFieldValue(Object instance, String fieldName, Object value) Sets the field value
static void	setFieldValue(Object instance, String fieldName, Object value) Sets the field value

Methods inherited from class java.lang.Object

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

Method Detail

getManifestAttributes

public static Attributes getManifestAttributes()

getDeclaredFieldValue

public static Object getDeclaredFieldValue(String fieldName,
                                           Object instance)

Gets the value of a field

Parameters:

fieldName - the field name

instance - the instance

Returns:

the return value

getDeclaredStaticFieldValue

public static Object getDeclaredStaticFieldValue(String fieldName,
                                                 Class<?> klass)

Gets the value of a field

Parameters:

fieldName - the field name

klass - the class

Returns:

the return value

getStaticFieldValue

public static Object getStaticFieldValue(String fieldName,
                                         Class<?> klass)

Gets the value of a field

Parameters:

fieldName - the field name

klass - the class

Returns:

the return value

getFieldValue

public static Object getFieldValue(String fieldName,
                                   Object instance)

Gets the value of a field

Parameters:

fieldName - the field name

instance - the instance

Returns:

the return value

setDeclaredFieldValue

public static void setDeclaredFieldValue(Object instance,
                                         String fieldName,
                                         Object value)

Sets the field value

Parameters:

instance - the object

fieldName - the field name

value - the value

setFieldValue

public static void setFieldValue(Object instance,
                                 String fieldName,
                                 Object value)

Sets the field value

Parameters:

instance - the object

fieldName - the field name

value - the value

getFieldValue

public static Object getFieldValue(Field field,
                                   Object instance)

Gets the value of a field

Parameters:

field - the field

instance - the instance

Returns:

the return value

isPrimitiveWrapperOf

public static boolean isPrimitiveWrapperOf(Class<?> targetClass,
                                           Class<?> primitive)

Returns true if the class is a primitive wrapper

Parameters:

targetClass - target class

primitive - primitive class

Returns:

if the class is a primitive wrapper

isAssignableTo

public static boolean isAssignableTo(Class<?> from,
                                     Class<?> to)

More powerful variant of Class.isAssignableFrom that supports primitives. Because Oracle cannot be bothered to update their ancient API.

Parameters:

from - from class

to - to class

Returns:

if to can be assigned from from

newInstance

public static Object newInstance(Class<?> klass,
                                 Object... args)

Creates a new class instance. Can handle primitives Can handle enums

Parameters:

klass - instantiated class

args - for primitives, ignored. For classes passed to the constructor

Returns:

instance

getEnumValues

public static <E extends Enum> E[] getEnumValues(Class<?> enumClass)
                                          throws NoSuchFieldException,
                                                 IllegalAccessException

Gets all enum values via reflection

Type Parameters:

E - the enum class

Parameters:

enumClass - the enum class

Returns:

all enum values

Throws:

NoSuchFieldException - triggered by reflection

IllegalAccessException - triggered by reflection

invokeMethod

public static Object invokeMethod(Object target,
                                  String functionName,
                                  Object... args)

Calls a function and returns its output

Parameters:

target - The object

functionName - the function

Returns:

the output

hasDefaultConstructor

public static boolean hasDefaultConstructor(Class<?> klass)

Returns true if the class has a default constructor

Parameters:

klass - the class

Returns:

if the class has a default constructor

isAbstractOrInterface

public static boolean isAbstractOrInterface(Class<?> klass)

getClassDistance

public static int getClassDistance(Class<?> parent,
                                   Class<?> child)

The number of hierarchy classes between two classes.

Parameters:

parent - the parent class or interface

child - the child class or interface

Returns:

the number of steps. zero if parent = child. -1 if not assignable.