Class ReflectTools
- java.lang.Object
-
- com.vaadin.flow.internal.ReflectTools
-
- All Implemented Interfaces:
Serializable
public class ReflectTools extends Object implements Serializable
An util class with helpers for reflection operations. Used internally by Vaadin and should not be used by application developers. Subject to change at any time.For internal use only. May be renamed or removed in a future release.
- Since:
- 1.0
- See Also:
- Serialized Form
-
-
Constructor Summary
Constructors Constructor Description ReflectTools()
-
Method Summary
All Methods Static Methods Concrete Methods Modifier and Type Method Description static void
checkClassAccessibility(Class<?> clazz)
Makes a check whether theclazz
is externally accessible for instantiation (e.g.static Class<?>
convertPrimitiveType(Class<?> type)
Converts the given primitive type to its boxed version.static <T> T
createInstance(Class<T> cls)
Creates an instance of the given class with a no-arg constructor.static Type
createParameterizedType(Class<?> rawType, Type subType)
Creates a parameterized type, e.g.static <T> T
createProxyInstance(Class<T> proxyClass, Class<?> originalClass)
Creates an instance of the givenproxyClass
with no-arg constructor.static Optional<ClassLoader>
findClosestCommonClassLoaderAncestor(ClassLoader classLoaderA, ClassLoader classLoaderB)
Finds the common ancestor of the twoClassLoaders
.static Class<?>
findCommonBaseType(Class<?> a, Class<?> b)
Finds the most specific class that both provided classes extend from.static Method
findMethod(Class<?> cls, String methodName, Class<?>... parameterTypes)
Locates the method in the given class.static Optional<Annotation>
getAnnotation(AnnotatedElement element, String annotationFqn)
Gets annotation ofelement
whose FQN isannotationFqn
.static Object
getAnnotationMethodValue(Annotation annotation, String methodName)
Gets the annotation method return value.static List<Integer>
getConstantIntValues(Class<?> clazz)
Collect all the integer values for public static final constants found for the given class.static Method
getFunctionalMethod(Class<?> functionalClass)
Get the functional interface method name defined for given interface class.static Class<?>
getGenericInterfaceType(Class<?> clazz, Class<?> interfaceType)
Finds the Class type for the generic interface class extended by given class if exists.static List<Class<?>>
getGenericInterfaceTypes(Class<?> clazz, Class<?> interfaceType)
Finds the Class type for all parameters defined by the generic interface class extended by given class if exists.static Optional<Method>
getGetter(Class<? extends Object> beanClass, String propertyName)
Finds a getter for a property in a bean type.static Stream<Method>
getGetterMethods(Class<?> type)
Return all the getter methods from the given type.static Object
getJavaFieldValue(Object object, Field field)
Returns the value of the java field.static Object
getJavaFieldValue(Object object, Field field, Class<?> propertyType)
Returns the value of the java field that is assignable to the property type.static Serializable
getPrimitiveDefaultValue(Class<?> primitiveType)
Gets default value for givenprimitiveType
.static String
getPropertyName(Method method)
Parses the property name from the given getter or setter method.static Type
getPropertyType(Method method)
Returns property type from the given getter or setter method.static Stream<Method>
getSetterMethods(Class<?> type)
Return all the setter methods from the given type.static boolean
hasAnnotation(AnnotatedElement element, String annotationFqn)
Checks whether theelement
has annotation whose FQN isannotationFqn
.static boolean
hasAnnotationWithSimpleName(AnnotatedElement element, String simpleName)
Checks whether theelement
has annotation whose simple name issimpleName
.static boolean
isCheckedException(Class<?> exceptionClass)
Checks if the given exception class represents a checked exception.static boolean
isGetter(Method method)
Checks whether the given method is a valid getter according to JavaBeans Specification.static boolean
isGetterName(String methodName, boolean isBoolean)
Checks whether the given method name is a valid getter name according to the JavaBeans Specification.static boolean
isInstantiableService(Class<?> clazz)
Check if a class can be instantiated via its default constructor via reflection.static boolean
isNotObjectMethod(Method method)
Returns whether the given method is NOT declared inObject
.static boolean
isSetter(Method method)
Checks whether the given method is a valid setter according to the JavaBeans Specification.static boolean
isSetterName(String methodName)
Checks whether the given method name is a valid setter name according to the JavaBeans Specification.static void
setJavaFieldValue(Object object, Field field, Object value)
Sets the value of a java field.
-
-
-
Method Detail
-
findMethod
public static Method findMethod(Class<?> cls, String methodName, Class<?>... parameterTypes) throws ExceptionInInitializerError
Locates the method in the given class. Returns null if the method is not found. Throws an ExceptionInInitializerError if there is a problem locating the method as this is mainly called from static blocks.- Parameters:
cls
- Class that contains the methodmethodName
- The name of the methodparameterTypes
- The parameter types for the method.- Returns:
- A reference to the method
- Throws:
ExceptionInInitializerError
- Wraps any exception in anExceptionInInitializerError
so this method can be called from a static initializer.
-
getJavaFieldValue
public static Object getJavaFieldValue(Object object, Field field) throws IllegalArgumentException, IllegalAccessException, InvocationTargetException
Returns the value of the java field.Uses getter if present, otherwise tries to access even private fields directly.
- Parameters:
object
- The object containing the fieldfield
- The field we want to get the value for- Returns:
- The value of the field in the object
- Throws:
InvocationTargetException
- If the value could not be retrievedIllegalAccessException
- If the value could not be retrievedIllegalArgumentException
- If the value could not be retrieved
-
getJavaFieldValue
public static Object getJavaFieldValue(Object object, Field field, Class<?> propertyType) throws IllegalArgumentException, IllegalAccessException, InvocationTargetException
Returns the value of the java field that is assignable to the property type.Uses getter if a getter for the correct return type is present, otherwise tries to access even private fields directly. If the java field is not assignable to the property type throws an IllegalArgumentException.
- Parameters:
object
- The object containing the fieldfield
- The field we want to get the value forpropertyType
- The type the field must be assignable to- Returns:
- The value of the field in the object
- Throws:
InvocationTargetException
- If the value could not be retrievedIllegalAccessException
- If the value could not be retrievedIllegalArgumentException
- If the value could not be retrieved
-
setJavaFieldValue
public static void setJavaFieldValue(Object object, Field field, Object value) throws IllegalArgumentException
Sets the value of a java field.- Parameters:
object
- The object containing the fieldfield
- The field we want to set the value forvalue
- The value to set- Throws:
IllegalArgumentException
- If the value could not be assigned to the field
-
convertPrimitiveType
public static Class<?> convertPrimitiveType(Class<?> type)
Converts the given primitive type to its boxed version.- Parameters:
type
- the primitive type to convert- Returns:
- the corresponding boxed type
-
getPrimitiveDefaultValue
public static Serializable getPrimitiveDefaultValue(Class<?> primitiveType)
Gets default value for givenprimitiveType
.- Parameters:
primitiveType
- the primitive type- Returns:
- the corresponding default value
-
isSetter
public static boolean isSetter(Method method)
Checks whether the given method is a valid setter according to the JavaBeans Specification.- Parameters:
method
- the method to check- Returns:
true
if the method is a setter,false
if not
-
isSetterName
public static boolean isSetterName(String methodName)
Checks whether the given method name is a valid setter name according to the JavaBeans Specification.- Parameters:
methodName
- the method name to check- Returns:
true
if the method name is a setter name,false
if not
-
isGetterName
public static boolean isGetterName(String methodName, boolean isBoolean)
Checks whether the given method name is a valid getter name according to the JavaBeans Specification.- Parameters:
methodName
- the method name to checkisBoolean
- whether the method is getter for boolean type- Returns:
true
if the method name is a getter name,false
if not
-
isGetter
public static boolean isGetter(Method method)
Checks whether the given method is a valid getter according to JavaBeans Specification.- Parameters:
method
- the method to check- Returns:
true
if the method is a getter,false
if not
-
getGetterMethods
public static Stream<Method> getGetterMethods(Class<?> type)
Return all the getter methods from the given type.Any getter methods from
Object
are excluded.- Parameters:
type
- the type to get getters from- Returns:
- a stream of getter methods
-
getSetterMethods
public static Stream<Method> getSetterMethods(Class<?> type)
Return all the setter methods from the given type.- Parameters:
type
- the type to get setters from- Returns:
- a stream of setter methods
-
isNotObjectMethod
public static boolean isNotObjectMethod(Method method)
Returns whether the given method is NOT declared inObject
.- Parameters:
method
- the method to check- Returns:
true
if method is NOT declared in Object,false
if it is
-
getPropertyName
public static String getPropertyName(Method method)
Parses the property name from the given getter or setter method.If the given method does not have a valid setter or getter name, this method may produce unexpected results.
- Parameters:
method
- the method to parse- Returns:
- the name of the property
- See Also:
isSetter(Method)
,isGetter(Method)
-
getPropertyType
public static Type getPropertyType(Method method)
Returns property type from the given getter or setter method.- Parameters:
method
- the method to inspect- Returns:
- the property type
- See Also:
isSetter(Method)
,isGetter(Method)
-
createInstance
public static <T> T createInstance(Class<T> cls)
Creates an instance of the given class with a no-arg constructor.Catches all exceptions which might occur and wraps them in a
IllegalArgumentException
with a descriptive error message hinting of what might be wrong with the class that could not be instantiated.- Type Parameters:
T
- the instance type- Parameters:
cls
- the class to instantiate- Returns:
- an instance of the class
-
createProxyInstance
public static <T> T createProxyInstance(Class<T> proxyClass, Class<?> originalClass)
Creates an instance of the givenproxyClass
with no-arg constructor.Catches all exceptions which might occur and wraps them in a
IllegalArgumentException
with a descriptive error message hinting of what might be wrong with the class that could not be instantiated. Descriptive message is derived based on the information about theoriginalClass
.- Type Parameters:
T
- type of a proxy class- Parameters:
proxyClass
- the proxy class to instantiateoriginalClass
- the class that is used to determine exception description, if creation fails- Returns:
- instance of a proxyClass
- Throws:
IllegalArgumentException
- if class instance creation fails
-
checkClassAccessibility
public static void checkClassAccessibility(Class<?> clazz)
Makes a check whether theclazz
is externally accessible for instantiation (e.g. it's not inner class (nested and not static) and is not a local class).- Parameters:
clazz
- type to check
-
createParameterizedType
public static Type createParameterizedType(Class<?> rawType, Type subType)
Creates a parameterized type, e.g.List<Bean>
.- Parameters:
rawType
- the raw type, e.g.List
subType
- the sub type, e.g.Bean
- Returns:
- a parameterized type
-
getGenericInterfaceType
public static Class<?> getGenericInterfaceType(Class<?> clazz, Class<?> interfaceType)
Finds the Class type for the generic interface class extended by given class if exists.- Parameters:
clazz
- class that should extend interfaceinterfaceType
- class type of interface to get generic for- Returns:
- Class if found else
null
-
getGenericInterfaceTypes
public static List<Class<?>> getGenericInterfaceTypes(Class<?> clazz, Class<?> interfaceType)
Finds the Class type for all parameters defined by the generic interface class extended by given class if exists.- Parameters:
clazz
- class that should extend interfaceinterfaceType
- class type of interface to get generic for- Returns:
- List of Class if found else empty List, never null
-
getGetter
public static Optional<Method> getGetter(Class<? extends Object> beanClass, String propertyName)
Finds a getter for a property in a bean type.- Parameters:
beanClass
- the bean type, notnull
propertyName
- the property name, notnull
- Returns:
- a getter method, or an empty optional if the bean type has no readable property with the provided name
-
isCheckedException
public static boolean isCheckedException(Class<?> exceptionClass)
Checks if the given exception class represents a checked exception.- Parameters:
exceptionClass
- the class to check- Returns:
true
if the class represents a checked exception, false otherwise
-
getFunctionalMethod
public static Method getFunctionalMethod(Class<?> functionalClass)
Get the functional interface method name defined for given interface class.- Parameters:
functionalClass
- interface class to get the functional method for- Returns:
- functional interface method
-
getConstantIntValues
public static List<Integer> getConstantIntValues(Class<?> clazz)
Collect all the integer values for public static final constants found for the given class.- Parameters:
clazz
- class to collect constants from- Returns:
- list of all integer constants in class
-
findCommonBaseType
public static Class<?> findCommonBaseType(Class<?> a, Class<?> b)
Finds the most specific class that both provided classes extend from.- Parameters:
a
- one class to get the base type for, notnull
b
- another class to get the base type for, notnull
- Returns:
- the most specific base class, not
null
- Throws:
IllegalArgumentException
- if a or b are interfaces or primitive types
-
findClosestCommonClassLoaderAncestor
public static Optional<ClassLoader> findClosestCommonClassLoaderAncestor(ClassLoader classLoaderA, ClassLoader classLoaderB)
Finds the common ancestor of the twoClassLoaders
. The class loaders themselves are acceptable ancestors; If they are equal,classLoaderA
is returned. An empty optional is returned if the two class loaders aren't equal, no shared ancestor is found, or the implementation of the class loader treats bootstrap class loader asnull
when it is the parent of a class loaders (seeClassLoader.getParent()
.- Parameters:
classLoaderA
- class loader AclassLoaderB
- class loader B- Returns:
- a common ancestor both class loaders share, or an empty optional
if there is no shared ancestor. Or if the implementation treats
bootstrap loaders as
null
(as perClassLoader.getParent()
).
-
hasAnnotation
public static boolean hasAnnotation(AnnotatedElement element, String annotationFqn)
Checks whether theelement
has annotation whose FQN isannotationFqn
.- Parameters:
element
- annotated element (field, method, etc.)annotationFqn
- annotation FQN- Returns:
true
iselement
has annotation whose FQN isannotationFqn
,false
otherwise
-
hasAnnotationWithSimpleName
public static boolean hasAnnotationWithSimpleName(AnnotatedElement element, String simpleName)
Checks whether theelement
has annotation whose simple name issimpleName
.- Parameters:
element
- annotated element (field, method, etc.)simpleName
- annotation simple name- Returns:
true
iselement
has annotation whose simple name issimpleName
,false
otherwise
-
getAnnotationMethodValue
public static Object getAnnotationMethodValue(Annotation annotation, String methodName)
Gets the annotation method return value.- Parameters:
annotation
- the annotationmethodName
- the method name- Returns:
- an optional value, or an empty optional if element has no
annotation with required
annotationFqn
-
getAnnotation
public static Optional<Annotation> getAnnotation(AnnotatedElement element, String annotationFqn)
Gets annotation ofelement
whose FQN isannotationFqn
.- Parameters:
element
- annotated element (field, method, etc.)annotationFqn
- annotation FQN- Returns:
- an optional annotation, or an empty optional if element has no
annotation with required
annotationFqn
-
isInstantiableService
public static boolean isInstantiableService(Class<?> clazz)
Check if a class can be instantiated via its default constructor via reflection.- Parameters:
clazz
- the class to check- Returns:
- true if the class can be instantiated, otherwise false
-
-