jodd.util

Class ReflectUtil

java.lang.Object

jodd.util.ReflectUtil

public class ReflectUtil
extends java.lang.Object

Various java.lang.reflect utilities.

Field Summary

Fields

Modifier and Type	Field and Description
static java.lang.String	METHOD_GET_PREFIX
static java.lang.String	METHOD_IS_PREFIX
static java.lang.String	METHOD_SET_PREFIX
static java.lang.Object[]	NO_ARGUMENTS Empty object array.
static java.lang.Class[]	NO_PARAMETERS Empty class array.
static java.lang.reflect.Type[]	NO_TYPES Empty type array.

Constructor Summary

Constructors

Constructor and Description
ReflectUtil()

Method Summary

Methods

Modifier and Type	Method and Description
static boolean	compareDeclarations(java.lang.reflect.Method first, java.lang.reflect.Method second) Compares method declarations: signature and return types.
static boolean	compareParameters(java.lang.Class[] first, java.lang.Class[] second) Compares method or ctor parameters.
static boolean	compareSignatures(java.lang.reflect.Constructor first, java.lang.reflect.Constructor second) Compares constructor signatures: names and parameters.
static boolean	compareSignatures(java.lang.reflect.Field first, java.lang.reflect.Field second)
static boolean	compareSignatures(java.lang.reflect.Method first, java.lang.reflect.Method second) Compares method signatures: names and parameters.
static java.lang.reflect.Method	findDeclaredMethod(java.lang.Class c, java.lang.String methodName)
static java.lang.reflect.Method	findMethod(java.lang.Class c, java.lang.String methodName) Returns method from an object, matched by name.
static void	forceAccess(java.lang.reflect.AccessibleObject accObject) Suppress access check against a reflection object.
static java.lang.reflect.Field[]	getAccessibleFields(java.lang.Class clazz)
static java.lang.reflect.Field[]	getAccessibleFields(java.lang.Class clazz, java.lang.Class limit)
static java.lang.reflect.Method[]	getAccessibleMethods(java.lang.Class clazz) Returns array of all methods that are accessible from given class.
static java.lang.reflect.Method[]	getAccessibleMethods(java.lang.Class clazz, java.lang.Class limit) Returns array of all methods that are accessible from given class, upto limit (usually Object.class).
static java.lang.String	getBeanPropertyGetterName(java.lang.reflect.Method method) Returns beans property getter name or null if method is not a real getter.
static java.lang.String	getBeanPropertySetterName(java.lang.reflect.Method method) Returns beans property setter name or null if method is not a real setter.
static java.lang.Class	getCallerClass(int framesToSkip) Emulates Reflection.getCallerClass using standard API.
static java.lang.Class[]	getClasses(java.lang.Object... objects) Returns classes from array of specified objects.
static java.lang.Class	getComponentType(java.lang.reflect.Type type)
static java.lang.Class	getComponentType(java.lang.reflect.Type type, java.lang.Class implClass)
static java.lang.Class	getComponentType(java.lang.reflect.Type type, java.lang.Class implClass, int index) Returns the component type of the given type.
static java.lang.Class	getComponentType(java.lang.reflect.Type type, int index)
static java.lang.Class	getGenericSupertype(java.lang.Class type)
static java.lang.Class	getGenericSupertype(java.lang.Class type, int index) Returns generic supertype for given class and 0-based index.
static java.lang.reflect.Method	getMethod0(java.lang.Class c, java.lang.String name, java.lang.Class... parameterTypes) Invokes private Class.getMethod0() without throwing NoSuchMethodException.
static java.lang.Class	getRawType(java.lang.reflect.Type type) Returns raw class for given type.
static java.lang.Class<?>	getRawType(java.lang.reflect.Type type, java.lang.Class implClass) Returns raw class for given type when implementation class is known and it makes difference.
static java.lang.Class[]	getSuperclasses(java.lang.Class type) Returns all superclasses.
static java.lang.reflect.Field[]	getSupportedFields(java.lang.Class clazz)
static java.lang.reflect.Field[]	getSupportedFields(java.lang.Class clazz, java.lang.Class limit)
static java.lang.reflect.Method[]	getSupportedMethods(java.lang.Class clazz)
static java.lang.reflect.Method[]	getSupportedMethods(java.lang.Class clazz, java.lang.Class limit) Returns a Method array of the methods to which instances of the specified respond except for those methods defined in the class specified by limit or any of its superclasses.
static java.lang.Object	invoke(java.lang.Class c, java.lang.Object obj, java.lang.String method, java.lang.Class[] paramClasses, java.lang.Object[] params) Invokes accessible method of an object.
static java.lang.Object	invoke(java.lang.Class c, java.lang.Object obj, java.lang.String method, java.lang.Object... params)
static java.lang.Object	invoke(java.lang.Class c, java.lang.String method, java.lang.Class[] paramClasses, java.lang.Object[] params) Invokes static method.
static java.lang.Object	invoke(java.lang.Class c, java.lang.String method, java.lang.Object... params) Invokes static method.
static java.lang.Object	invoke(java.lang.Object obj, java.lang.String method, java.lang.Class[] paramClasses, java.lang.Object[] params) Invokes accessible method of an object.
static java.lang.Object	invoke(java.lang.Object obj, java.lang.String method, java.lang.Object... params) Invokes accessible method of an object without specifying parameter types.
static java.lang.Object	invokeDeclared(java.lang.Class c, java.lang.Object obj, java.lang.String method, java.lang.Class[] paramClasses, java.lang.Object[] params) Invokes any method of a class, even private ones.
static java.lang.Object	invokeDeclared(java.lang.Class c, java.lang.Object obj, java.lang.String method, java.lang.Object... params)
static java.lang.Object	invokeDeclared(java.lang.Class c, java.lang.String method, java.lang.Class[] paramClasses, java.lang.Object[] params)
static java.lang.Object	invokeDeclared(java.lang.Class c, java.lang.String method, java.lang.Object... params)
static java.lang.Object	invokeDeclared(java.lang.Object obj, java.lang.String method, java.lang.Class[] paramClasses, java.lang.Object[] params) Invokes any method of a class suppressing java access checking.
static java.lang.Object	invokeDeclared(java.lang.Object obj, java.lang.String method, java.lang.Object... params)
static boolean	isAssignableFrom(java.lang.reflect.Member member1, java.lang.reflect.Member member2) Returns true if the first member is accessible from second one.
static boolean	isBeanProperty(java.lang.reflect.Method method) Returns true if method is a bean property.
static boolean	isBeanPropertyGetter(java.lang.reflect.Method method) Returns true if method is bean getter.
static boolean	isBeanPropertySetter(java.lang.reflect.Method method) Returns true if method is bean setter.
static boolean	isInstanceOf(java.lang.Object o, java.lang.Class target) Dynamic version of instanceof.
static boolean	isInterfaceImpl(java.lang.Class thisClass, java.lang.Class targetInterface) Returns true if provided class is interface implementation.
static boolean	isObjectMethod(java.lang.reflect.Method method) Returns true if method defined in Object class.
static boolean	isPublic(java.lang.Class c) Returns true if class is public.
static boolean	isPublic(java.lang.reflect.Member member) Returns true if class member is public.
static boolean	isPublicPublic(java.lang.reflect.Member member) Returns true if class member is public and if its declaring class is also public.
static boolean	isSubclass(java.lang.Class thisClass, java.lang.Class target) Determines if first class match the destination and simulates kind of instanceof.
static boolean	isUserDefinedMethod(java.lang.reflect.Method method) Returns true if method is user defined and not defined in Object class.
static java.lang.Object	newInstance(java.lang.Class type) Creates new instances including for common mutable classes that do not have a default constructor.
static java.lang.Object	readAnnotationValue(java.lang.annotation.Annotation annotation, java.lang.String name) Reads annotation value.
static java.lang.reflect.Type	resolveVariable(java.lang.reflect.TypeVariable variable, java.lang.Class implClass) Resolves TypeVariable with given implementation class.
static java.lang.String	typeToString(java.lang.reflect.Type type) Converts Type to a String.

Methods inherited from class java.lang.Object

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

Field Detail

NO_PARAMETERS

public static final java.lang.Class[] NO_PARAMETERS

Empty class array.

NO_ARGUMENTS

public static final java.lang.Object[] NO_ARGUMENTS

Empty object array.

NO_TYPES

public static final java.lang.reflect.Type[] NO_TYPES

Empty type array.

METHOD_GET_PREFIX

public static final java.lang.String METHOD_GET_PREFIX

See Also:

Constant Field Values

METHOD_IS_PREFIX

public static final java.lang.String METHOD_IS_PREFIX

See Also:

Constant Field Values

METHOD_SET_PREFIX

public static final java.lang.String METHOD_SET_PREFIX

See Also:

Constant Field Values

Constructor Detail

ReflectUtil

public ReflectUtil()

Method Detail

getMethod0

public static java.lang.reflect.Method getMethod0(java.lang.Class c,
                                  java.lang.String name,
                                  java.lang.Class... parameterTypes)

Invokes private Class.getMethod0() without throwing NoSuchMethodException. Returns only public methods or null if method not found. Since no exception is throwing, it works faster.

Parameters:

c - class to inspect

name - name of method to find

parameterTypes - parameter types

Returns:

founded method, or null

findMethod

public static java.lang.reflect.Method findMethod(java.lang.Class c,
                                  java.lang.String methodName)

Returns method from an object, matched by name. This may be considered as a slow operation, since methods are matched one by one. Returns only accessible methods. Only first method is matched.

Parameters:

c - class to examine

methodName - Full name of the method.

Returns:

null if method not found

findDeclaredMethod

public static java.lang.reflect.Method findDeclaredMethod(java.lang.Class c,
                                          java.lang.String methodName)

See Also:

findMethod(Class, String)

getClasses

public static java.lang.Class[] getClasses(java.lang.Object... objects)

Returns classes from array of specified objects.

invoke

public static java.lang.Object invoke(java.lang.Class c,
                      java.lang.Object obj,
                      java.lang.String method,
                      java.lang.Class[] paramClasses,
                      java.lang.Object[] params)
                               throws java.lang.IllegalAccessException,
                                      java.lang.NoSuchMethodException,
                                      java.lang.reflect.InvocationTargetException

Invokes accessible method of an object.

Parameters:

c - class that contains method

obj - object to execute

method - method to invoke

paramClasses - classes of parameters

params - parameters

Throws:

java.lang.IllegalAccessException

java.lang.NoSuchMethodException

java.lang.reflect.InvocationTargetException

invoke

public static java.lang.Object invoke(java.lang.Class c,
                      java.lang.String method,
                      java.lang.Class[] paramClasses,
                      java.lang.Object[] params)
                               throws java.lang.IllegalAccessException,
                                      java.lang.NoSuchMethodException,
                                      java.lang.reflect.InvocationTargetException

Invokes static method.

Throws:

java.lang.IllegalAccessException

java.lang.NoSuchMethodException

java.lang.reflect.InvocationTargetException

invoke

public static java.lang.Object invoke(java.lang.Object obj,
                      java.lang.String method,
                      java.lang.Class[] paramClasses,
                      java.lang.Object[] params)
                               throws java.lang.IllegalAccessException,
                                      java.lang.NoSuchMethodException,
                                      java.lang.reflect.InvocationTargetException

Invokes accessible method of an object.

Parameters:

obj - object

method - name of the objects method

params - method parameters

paramClasses - method parameter types

Throws:

java.lang.IllegalAccessException

java.lang.NoSuchMethodException

java.lang.reflect.InvocationTargetException

invoke

public static java.lang.Object invoke(java.lang.Object obj,
                      java.lang.String method,
                      java.lang.Object... params)
                               throws java.lang.IllegalAccessException,
                                      java.lang.NoSuchMethodException,
                                      java.lang.reflect.InvocationTargetException

Invokes accessible method of an object without specifying parameter types.

Parameters:

obj - object

method - method of an object

params - method parameters

Throws:

java.lang.IllegalAccessException

java.lang.NoSuchMethodException

java.lang.reflect.InvocationTargetException

invoke

public static java.lang.Object invoke(java.lang.Class c,
                      java.lang.Object obj,
                      java.lang.String method,
                      java.lang.Object... params)
                               throws java.lang.IllegalAccessException,
                                      java.lang.NoSuchMethodException,
                                      java.lang.reflect.InvocationTargetException

Throws:

java.lang.IllegalAccessException

java.lang.NoSuchMethodException

java.lang.reflect.InvocationTargetException

invoke

public static java.lang.Object invoke(java.lang.Class c,
                      java.lang.String method,
                      java.lang.Object... params)
                               throws java.lang.IllegalAccessException,
                                      java.lang.NoSuchMethodException,
                                      java.lang.reflect.InvocationTargetException

Invokes static method.

Throws:

java.lang.IllegalAccessException

java.lang.NoSuchMethodException

java.lang.reflect.InvocationTargetException

invokeDeclared

public static java.lang.Object invokeDeclared(java.lang.Class c,
                              java.lang.Object obj,
                              java.lang.String method,
                              java.lang.Class[] paramClasses,
                              java.lang.Object[] params)
                                       throws java.lang.IllegalAccessException,
                                              java.lang.NoSuchMethodException,
                                              java.lang.reflect.InvocationTargetException

Invokes any method of a class, even private ones.

Parameters:

c - class to examine

obj - object to inspect

method - method to invoke

paramClasses - parameter types

params - parameters

Throws:

java.lang.IllegalAccessException

java.lang.NoSuchMethodException

java.lang.reflect.InvocationTargetException

invokeDeclared

public static java.lang.Object invokeDeclared(java.lang.Class c,
                              java.lang.String method,
                              java.lang.Class[] paramClasses,
                              java.lang.Object[] params)
                                       throws java.lang.IllegalAccessException,
                                              java.lang.NoSuchMethodException,
                                              java.lang.reflect.InvocationTargetException

Throws:

java.lang.IllegalAccessException

java.lang.NoSuchMethodException

java.lang.reflect.InvocationTargetException

invokeDeclared

public static java.lang.Object invokeDeclared(java.lang.Object obj,
                              java.lang.String method,
                              java.lang.Class[] paramClasses,
                              java.lang.Object[] params)
                                       throws java.lang.IllegalAccessException,
                                              java.lang.NoSuchMethodException,
                                              java.lang.reflect.InvocationTargetException

Invokes any method of a class suppressing java access checking.

Parameters:

obj - object to inspect

method - method to invoke

paramClasses - parameter types

params - parameters

Throws:

java.lang.IllegalAccessException

java.lang.NoSuchMethodException

java.lang.reflect.InvocationTargetException

invokeDeclared

public static java.lang.Object invokeDeclared(java.lang.Object obj,
                              java.lang.String method,
                              java.lang.Object... params)
                                       throws java.lang.IllegalAccessException,
                                              java.lang.NoSuchMethodException,
                                              java.lang.reflect.InvocationTargetException

Throws:

java.lang.IllegalAccessException

java.lang.NoSuchMethodException

java.lang.reflect.InvocationTargetException

invokeDeclared

public static java.lang.Object invokeDeclared(java.lang.Class c,
                              java.lang.Object obj,
                              java.lang.String method,
                              java.lang.Object... params)
                                       throws java.lang.IllegalAccessException,
                                              java.lang.NoSuchMethodException,
                                              java.lang.reflect.InvocationTargetException

Throws:

java.lang.IllegalAccessException

java.lang.NoSuchMethodException

java.lang.reflect.InvocationTargetException

invokeDeclared

public static java.lang.Object invokeDeclared(java.lang.Class c,
                              java.lang.String method,
                              java.lang.Object... params)
                                       throws java.lang.IllegalAccessException,
                                              java.lang.NoSuchMethodException,
                                              java.lang.reflect.InvocationTargetException

Throws:

java.lang.IllegalAccessException

java.lang.NoSuchMethodException

java.lang.reflect.InvocationTargetException

isSubclass

public static boolean isSubclass(java.lang.Class thisClass,
                 java.lang.Class target)

Determines if first class match the destination and simulates kind of instanceof. All subclasses and interface of first class are examined against second class. Method is not symmetric.

isInterfaceImpl

public static boolean isInterfaceImpl(java.lang.Class thisClass,
                      java.lang.Class targetInterface)

Returns true if provided class is interface implementation.

isInstanceOf

public static boolean isInstanceOf(java.lang.Object o,
                   java.lang.Class target)

Dynamic version of instanceof.

Parameters:

o - object to match

target - target class

Returns:

true if object is an instance of target class

getAccessibleMethods

public static java.lang.reflect.Method[] getAccessibleMethods(java.lang.Class clazz)

Returns array of all methods that are accessible from given class.

See Also:

getAccessibleMethods(Class, Class)

getAccessibleMethods

public static java.lang.reflect.Method[] getAccessibleMethods(java.lang.Class clazz,
                                              java.lang.Class limit)

Returns array of all methods that are accessible from given class, upto limit (usually Object.class). Abstract methods are ignored.

getAccessibleFields

public static java.lang.reflect.Field[] getAccessibleFields(java.lang.Class clazz)

getAccessibleFields

public static java.lang.reflect.Field[] getAccessibleFields(java.lang.Class clazz,
                                            java.lang.Class limit)

getSupportedMethods

public static java.lang.reflect.Method[] getSupportedMethods(java.lang.Class clazz)

getSupportedMethods

public static java.lang.reflect.Method[] getSupportedMethods(java.lang.Class clazz,
                                             java.lang.Class limit)

Returns a Method array of the methods to which instances of the specified respond except for those methods defined in the class specified by limit or any of its superclasses. Note that limit is usually used to eliminate them methods defined by java.lang.Object. If limit is null then all methods are returned.

getSupportedFields

public static java.lang.reflect.Field[] getSupportedFields(java.lang.Class clazz)

getSupportedFields

public static java.lang.reflect.Field[] getSupportedFields(java.lang.Class clazz,
                                           java.lang.Class limit)

compareDeclarations

public static boolean compareDeclarations(java.lang.reflect.Method first,
                          java.lang.reflect.Method second)

Compares method declarations: signature and return types.

compareSignatures

public static boolean compareSignatures(java.lang.reflect.Method first,
                        java.lang.reflect.Method second)

Compares method signatures: names and parameters.

compareSignatures

public static boolean compareSignatures(java.lang.reflect.Constructor first,
                        java.lang.reflect.Constructor second)

Compares constructor signatures: names and parameters.

compareSignatures

public static boolean compareSignatures(java.lang.reflect.Field first,
                        java.lang.reflect.Field second)

compareParameters

public static boolean compareParameters(java.lang.Class[] first,
                        java.lang.Class[] second)

Compares method or ctor parameters.

forceAccess

public static void forceAccess(java.lang.reflect.AccessibleObject accObject)

Suppress access check against a reflection object. SecurityException is silently ignored. Checks first if the object is already accessible.

isPublic

public static boolean isPublic(java.lang.reflect.Member member)

Returns true if class member is public.

isPublicPublic

public static boolean isPublicPublic(java.lang.reflect.Member member)

Returns true if class member is public and if its declaring class is also public.

isPublic

public static boolean isPublic(java.lang.Class c)

Returns true if class is public.

newInstance

public static java.lang.Object newInstance(java.lang.Class type)
                                    throws java.lang.IllegalAccessException,
                                           java.lang.InstantiationException

Creates new instances including for common mutable classes that do not have a default constructor. more user-friendly. It examines if class is a map, list, String, Character, Boolean or a Number. Immutable instances are cached and not created again. Arrays are also created with no elements. Note that this bunch of if blocks is faster then using a HashMap.

Throws:

java.lang.IllegalAccessException

java.lang.InstantiationException

isAssignableFrom

public static boolean isAssignableFrom(java.lang.reflect.Member member1,
                       java.lang.reflect.Member member2)

Returns true if the first member is accessible from second one.

getSuperclasses

public static java.lang.Class[] getSuperclasses(java.lang.Class type)

Returns all superclasses.

isUserDefinedMethod

public static boolean isUserDefinedMethod(java.lang.reflect.Method method)

Returns true if method is user defined and not defined in Object class.

isObjectMethod

public static boolean isObjectMethod(java.lang.reflect.Method method)

Returns true if method defined in Object class.

isBeanProperty

public static boolean isBeanProperty(java.lang.reflect.Method method)

Returns true if method is a bean property.

isBeanPropertyGetter

public static boolean isBeanPropertyGetter(java.lang.reflect.Method method)

Returns true if method is bean getter.

getBeanPropertyGetterName

public static java.lang.String getBeanPropertyGetterName(java.lang.reflect.Method method)

Returns beans property getter name or null if method is not a real getter.

isBeanPropertySetter

public static boolean isBeanPropertySetter(java.lang.reflect.Method method)

Returns true if method is bean setter.

getBeanPropertySetterName

public static java.lang.String getBeanPropertySetterName(java.lang.reflect.Method method)

Returns beans property setter name or null if method is not a real setter.

getComponentType

public static java.lang.Class getComponentType(java.lang.reflect.Type type)

getComponentType

public static java.lang.Class getComponentType(java.lang.reflect.Type type,
                               java.lang.Class implClass)

getComponentType

public static java.lang.Class getComponentType(java.lang.reflect.Type type,
                               int index)

getComponentType

public static java.lang.Class getComponentType(java.lang.reflect.Type type,
                               java.lang.Class implClass,
                               int index)

Returns the component type of the given type. Returns null if given type does not have a single component type. For example the following types all have the component-type MyClass:

• MyClass[]
• List<MyClass>
• Foo<? extends MyClass>
• Bar<? super MyClass>
• <T extends MyClass> T[]

Index represents the index of component type, when class supports more then one. For example, Map<A, B> has 2 component types. If index is 0 or positive, than it represents order of component type. If the value is negative, then it represents component type counted from the end! Therefore, the default value of -1 always returns the last component type.

getGenericSupertype

public static java.lang.Class getGenericSupertype(java.lang.Class type,
                                  int index)

Returns generic supertype for given class and 0-based index.

See Also:

getComponentType(java.lang.reflect.Type, int)

getGenericSupertype

public static java.lang.Class getGenericSupertype(java.lang.Class type)

See Also:

getComponentType(java.lang.reflect.Type)

getRawType

public static java.lang.Class getRawType(java.lang.reflect.Type type)

Returns raw class for given type. Use this method with both regular and generic types.

Parameters:

type - the type to convert

Returns:

the closest class representing the given type

See Also:

getRawType(java.lang.reflect.Type, Class)

getRawType

public static java.lang.Class<?> getRawType(java.lang.reflect.Type type,
                            java.lang.Class implClass)

Returns raw class for given type when implementation class is known and it makes difference.

See Also:

resolveVariable(java.lang.reflect.TypeVariable, Class)

resolveVariable

public static java.lang.reflect.Type resolveVariable(java.lang.reflect.TypeVariable variable,
                                     java.lang.Class implClass)

Resolves TypeVariable with given implementation class.

typeToString

public static java.lang.String typeToString(java.lang.reflect.Type type)

Converts Type to a String. Supports successor interfaces:

• java.lang.Class - represents usual class
• java.lang.reflect.ParameterizedType - class with generic parameter (e.g. List)
• java.lang.reflect.TypeVariable - generic type literal (e.g. List, T - type variable)
• java.lang.reflect.WildcardType - wildcard type (List<? extends Number>, "? extends Number - wildcard type)
• java.lang.reflect.GenericArrayType - type for generic array (e.g. T[], T - array type)

readAnnotationValue

public static java.lang.Object readAnnotationValue(java.lang.annotation.Annotation annotation,
                                   java.lang.String name)

Reads annotation value. Returns null on error (e.g. when value name not found).

getCallerClass

public static java.lang.Class getCallerClass(int framesToSkip)

Emulates Reflection.getCallerClass using standard API. This implementation uses custom SecurityManager and it is the fastest. Other implementations are:

• new Throwable().getStackTrace()[callStackDepth]
• Thread.currentThread().getStackTrace()[callStackDepth] (the slowest)

In case when usage of SecurityManager is not allowed, this method fails back to the second implementation.

Note that original Reflection.getCallerClass is way faster then any emulation.