@API(value=Internal) public final class ReflectionUtils extends Object
These utilities are intended solely for usage within the JUnit framework itself. Any usage by external parties is not supported. Use at your own risk!
| Modifier and Type | Class and Description |
|---|---|
static class |
ReflectionUtils.MethodSortOrder |
| Modifier and Type | Method and Description |
|---|---|
static List<Class<?>> |
findAllClassesInClasspathRoot(Path root,
Predicate<Class<?>> classTester,
Predicate<String> classNameFilter) |
static List<Class<?>> |
findAllClassesInPackage(String basePackageName,
Predicate<Class<?>> classTester,
Predicate<String> classNameFilter) |
static Optional<Method> |
findMethod(Class<?> clazz,
String methodName,
Class<?>... parameterTypes) |
static Optional<Method> |
findMethod(Class<?> clazz,
String methodName,
String parameterTypeNames) |
static List<Method> |
findMethods(Class<?> clazz,
Predicate<Method> predicate) |
static List<Method> |
findMethods(Class<?> clazz,
Predicate<Method> predicate,
ReflectionUtils.MethodSortOrder sortOrder) |
static List<Class<?>> |
findNestedClasses(Class<?> clazz,
Predicate<Class<?>> predicate) |
static Set<Class<?>> |
getAllAssignmentCompatibleClasses(Class<?> clazz)
Return all classes and interfaces that can be used as assignment types
for instances of the specified
Class, including itself. |
static Set<Path> |
getAllClasspathRootDirectories() |
static <T> Constructor<T> |
getDeclaredConstructor(Class<T> clazz)
Get the sole declared
Constructor for the supplied class. |
static ClassLoader |
getDefaultClassLoader() |
static Optional<Method> |
getMethod(Class<?> clazz,
String methodName,
Class<?>... parameterTypes) |
static Optional<Object> |
getOuterInstance(Object inner,
Class<?> targetType) |
static Class<?> |
getWrapperType(Class<?> type)
Get the wrapper type for the supplied primitive type.
|
static Object |
invokeMethod(Method method,
Object target,
Object... args)
Invoke the supplied method, making it accessible if necessary and
masking any
checked exception as an unchecked exception.
|
static boolean |
isAbstract(Class<?> clazz) |
static boolean |
isAbstract(Member member) |
static boolean |
isArray(Object obj)
Determine if the supplied object is an array.
|
static boolean |
isAssignableTo(Object obj,
Class<?> type)
Determine if the supplied object can be assigned to the supplied type
for the purpose of reflective method invocations.
|
static boolean |
isPackage(String packageName)
Determine if the supplied package name refers to a package that is present
in the classpath.
|
static boolean |
isPrivate(Class<?> clazz) |
static boolean |
isPrivate(Member member) |
static boolean |
isPublic(Class<?> clazz) |
static boolean |
isPublic(Member member) |
static boolean |
isStatic(Class<?> clazz) |
static boolean |
isStatic(Member member) |
static Optional<Class<?>> |
loadClass(String name)
Load a class by its fully qualified name.
|
static Optional<Class<?>> |
loadClass(String name,
ClassLoader classLoader)
Load a class by its fully qualified name, using the supplied
ClassLoader. |
static Optional<Method> |
loadMethod(String fullyQualifiedMethodName)
Load a method by its fully qualified name.
|
static <T> T |
newInstance(Class<T> clazz,
Object... args)
Create a new instance of the specified
Class by invoking
the constructor whose argument list matches the types of the supplied
arguments. |
static <T> T |
newInstance(Constructor<T> constructor,
Object... args)
Create a new instance of type
T by invoking the supplied constructor
with the supplied arguments. |
static <T> Optional<Object> |
readFieldValue(Class<T> clazz,
String fieldName,
T instance)
Read the value of a potentially inaccessible field.
|
public static ClassLoader getDefaultClassLoader()
public static boolean isPublic(Class<?> clazz)
public static boolean isPublic(Member member)
public static boolean isPrivate(Class<?> clazz)
public static boolean isPrivate(Member member)
public static boolean isAbstract(Class<?> clazz)
public static boolean isAbstract(Member member)
public static boolean isStatic(Class<?> clazz)
public static boolean isStatic(Member member)
public static boolean isArray(Object obj)
obj - the object to test; potentially nulltrue if the object is an arraypublic static boolean isAssignableTo(Object obj, Class<?> type)
In contrast to Class.isInstance(Object), this method returns
true if the supplied type represents a primitive type whose
wrapper matches the supplied object's type.
Returns true if the supplied object is null and the
supplied type does not represent a primitive type.
obj - the object to test for assignment compatibility; potentially nulltype - the type to check against; never nulltrue if the object is assignment compatibleClass.isInstance(Object),
Class.isAssignableFrom(Class)public static Class<?> getWrapperType(Class<?> type)
type - the primitive type for which to retrieve the wrapper typenull if the
supplied type is null or not a primitive typepublic static <T> T newInstance(Class<T> clazz, Object... args)
Class by invoking
the constructor whose argument list matches the types of the supplied
arguments.
The constructor will be made accessible if necessary, and any checked exception will be masked as an unchecked exception.
clazz - the class to instantiate; never nullargs - the arguments to pass to the constructor none of which may be nullnewInstance(Constructor, Object...),
ExceptionUtils.throwAsUncheckedException(Throwable)public static <T> T newInstance(Constructor<T> constructor, Object... args)
T by invoking the supplied constructor
with the supplied arguments.
The constructor will be made accessible if necessary, and any checked exception will be masked as an unchecked exception.
constructor - the constructor to invoke; never nullargs - the arguments to pass to the constructornullnewInstance(Class, Object...),
ExceptionUtils.throwAsUncheckedException(Throwable)public static Object invokeMethod(Method method, Object target, Object... args)
method - the method to invoke; never nulltarget - the object on which to invoke the method; may be
null if the method is staticargs - the arguments to pass to the methodnull
if the return type is voidExceptionUtils.throwAsUncheckedException(Throwable)public static Optional<Class<?>> loadClass(String name)
name - the fully qualified name of the class to load; never
null or blankloadClass(String, ClassLoader)public static Optional<Class<?>> loadClass(String name, ClassLoader classLoader)
ClassLoader.name - the fully qualified name of the class to load; never
null or blankclassLoader - the ClassLoader to use; never nullloadClass(String)public static Optional<Method> loadMethod(String fullyQualifiedMethodName)
The following formats are supported.
[fully qualified class name]#[methodName][fully qualified class name]#[methodName](parameter type list)
| Method | Fully Qualified Method Name |
|---|---|
CharSequence.chars() | java.lang.String#chars |
CharSequence.chars() | java.lang.String#chars() |
String.equalsIgnoreCase(String) | java.lang.String#equalsIgnoreCase(java.lang.String) |
String.substring(int, int) | java.lang.String#substring(int, int) |
fullyQualifiedMethodName - the fully qualified name of the method to load;
never null or blankOptional containing the method; never null but
potentially emptypublic static boolean isPackage(String packageName)
The default package is represented by an empty string ("").
packageName - the package name to check; never null and never
containing whitespace onlypublic static List<Class<?>> findAllClassesInClasspathRoot(Path root, Predicate<Class<?>> classTester, Predicate<String> classNameFilter)
public static List<Class<?>> findAllClassesInPackage(String basePackageName, Predicate<Class<?>> classTester, Predicate<String> classNameFilter)
public static List<Class<?>> findNestedClasses(Class<?> clazz, Predicate<Class<?>> predicate)
public static <T> Constructor<T> getDeclaredConstructor(Class<T> clazz)
Constructor for the supplied class.
Throws a PreconditionViolationException if the supplied
class declares more than one constructor.
clazz - the class to get the constructor fornullClass.getDeclaredConstructors()public static Optional<Method> getMethod(Class<?> clazz, String methodName, Class<?>... parameterTypes)
public static Optional<Method> findMethod(Class<?> clazz, String methodName, String parameterTypeNames)
public static Optional<Method> findMethod(Class<?> clazz, String methodName, Class<?>... parameterTypes)
public static List<Method> findMethods(Class<?> clazz, Predicate<Method> predicate, ReflectionUtils.MethodSortOrder sortOrder)
public static <T> Optional<Object> readFieldValue(Class<T> clazz, String fieldName, T instance)
If the field does not exist, an exception occurs while reading it, or
the value of the field is null, an empty Optional is
returned.
clazz - the class where the field is declared; never nullfieldName - the name of the field; never null or emptyinstance - the instance from where the value is to be read; may
be null for a static fieldpublic static Set<Class<?>> getAllAssignmentCompatibleClasses(Class<?> clazz)
Class, including itself.clazz - the Class to lookupClass.isAssignableFrom(java.lang.Class<?>)