io.flamingock.internal.util

Class ReflectionUtil

java.lang.Object

io.flamingock.internal.util.ReflectionUtil

public final class ReflectionUtil
extends java.lang.Object

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	ReflectionUtil.ConstructorNotFound
static class	ReflectionUtil.MultipleAnnotatedConstructorsFound
static class	ReflectionUtil.MultipleConstructorsFound

Method Summary

Modifier and Type	Method and Description
static java.util.List<javax.lang.model.element.ExecutableElement>	filterAnnotatedConstructors(java.util.List<javax.lang.model.element.ExecutableElement> constructorElements, java.lang.Class<? extends java.lang.annotation.Annotation> annotationClass)
static <A extends java.lang.annotation.Annotation> java.util.List<A>	findAllAnnotations(java.lang.Class<?> clazz, java.lang.Class<A> annotationType) Collects all instances of a specific annotation type from a class, its superclass hierarchy, and implemented interfaces.
static java.util.Optional<java.lang.reflect.Method>	findFirstAnnotatedMethod(java.lang.Class<?> source, java.lang.Class<? extends java.lang.annotation.Annotation> annotation)
static java.util.Optional<java.lang.reflect.Method>	findFirstMethodByName(java.lang.Class<?> source, java.lang.String methodName)
static java.lang.Class<?>[]	getActualTypeArguments(java.lang.Class<?> clazz) Retrieves the actual type arguments used in a class's generic superclass as Class objects.
static java.util.List<java.lang.reflect.Constructor<?>>	getAnnotatedConstructors(java.lang.Class<?> source, java.lang.Class<? extends java.lang.annotation.Annotation> annotationClass)
static java.lang.reflect.Constructor<?>	getConstructorFromParameterTypeNames(java.lang.Class<?> targetClass, java.util.List<java.lang.String> parameterTypeNames) Finds a constructor that matches the provided parameter type names.
static java.util.List<java.lang.reflect.Constructor<?>>	getConstructors(java.lang.Class<?> source)
static java.util.List<javax.lang.model.element.ExecutableElement>	getConstructors(javax.lang.model.element.TypeElement typeElement)
static java.lang.reflect.Constructor<?>	getConstructorWithAnnotationPreference(java.lang.Class<?> source, java.lang.Class<? extends java.lang.annotation.Annotation> annotationClass)
static javax.lang.model.element.ExecutableElement	getConstructorWithAnnotationPreference(javax.lang.model.element.TypeElement typeElement, java.lang.Class<? extends java.lang.annotation.Annotation> annotationClass)
static java.lang.reflect.Method	getDeclaredMethodFromParameterTypeNames(java.lang.Class<?> targetClass, java.lang.String methodName, java.util.List<java.lang.String> parameterTypeNames) Finds a declared method by name using your 3-step heuristic: 1) Filter declared methods by name.
static java.lang.reflect.Constructor<?>	getDefaultConstructor(java.lang.Class<?> targetClass) Finds the default constructor of a class
static java.util.List<java.lang.Class<?>>	getParameters(java.lang.reflect.Executable executable)
static java.util.List<java.lang.String>	getParametersTypesQualifiedNames(javax.lang.model.element.ExecutableElement element)
static java.util.Collection<java.lang.Class<?>>	loadAnnotatedClassesFromPackage(java.lang.String packagePath, java.lang.Class<? extends java.lang.annotation.Annotation>... annotations)
static java.lang.reflect.Type[]	resolveTypeArguments(java.lang.Class<?> concreteClass, java.lang.Class<?> targetGeneric) Resolves the type arguments that concreteClass supplies for the generic superclass or interface targetGeneric.
static java.lang.reflect.Type[]	resolveTypeArguments(java.lang.Object instance, java.lang.Class<?> targetGeneric) Convenience overload: uses the runtime class of the given instance.
static java.lang.Class<?>[]	resolveTypeArgumentsAsClasses(java.lang.Class<?> concreteClass, java.lang.Class<?> targetGeneric) Variant returning raw classes (defaults to Object.class if resolution fails).

Methods inherited from class java.lang.Object

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

Method Detail

getActualTypeArguments

public static java.lang.Class<?>[] getActualTypeArguments(java.lang.Class<?> clazz)

Retrieves the actual type arguments used in a class's generic superclass as Class objects. This method traverses the class hierarchy to find the first parameterized superclass and returns its type arguments as Class objects.

Parameters:

clazz - The class to analyze for generic type arguments

Returns:

An array of Class objects representing the actual type arguments

Throws:

java.lang.IllegalStateException - If no parameterized superclass can be found in the hierarchy

java.lang.ClassCastException - If any type argument is not a Class (e.g., type variable, wildcard)

resolveTypeArguments

public static java.lang.reflect.Type[] resolveTypeArguments(java.lang.Class<?> concreteClass,
                                                            java.lang.Class<?> targetGeneric)

Resolves the type arguments that concreteClass supplies for the generic superclass or interface targetGeneric.

Throws:

java.lang.IllegalArgumentException - if targetGeneric is not in the hierarchy of concreteClass.

resolveTypeArguments

public static java.lang.reflect.Type[] resolveTypeArguments(java.lang.Object instance,
                                                            java.lang.Class<?> targetGeneric)

Convenience overload: uses the runtime class of the given instance.

resolveTypeArgumentsAsClasses

public static java.lang.Class<?>[] resolveTypeArgumentsAsClasses(java.lang.Class<?> concreteClass,
                                                                 java.lang.Class<?> targetGeneric)

Variant returning raw classes (defaults to Object.class if resolution fails).

findFirstAnnotatedMethod

public static java.util.Optional<java.lang.reflect.Method> findFirstAnnotatedMethod(java.lang.Class<?> source,
                                                                                    java.lang.Class<? extends java.lang.annotation.Annotation> annotation)

findFirstMethodByName

public static java.util.Optional<java.lang.reflect.Method> findFirstMethodByName(java.lang.Class<?> source,
                                                                                 java.lang.String methodName)

loadAnnotatedClassesFromPackage

public static java.util.Collection<java.lang.Class<?>> loadAnnotatedClassesFromPackage(java.lang.String packagePath,
                                                                                       java.lang.Class<? extends java.lang.annotation.Annotation>... annotations)

getParameters

public static java.util.List<java.lang.Class<?>> getParameters(java.lang.reflect.Executable executable)

getAnnotatedConstructors

public static java.util.List<java.lang.reflect.Constructor<?>> getAnnotatedConstructors(java.lang.Class<?> source,
                                                                                        java.lang.Class<? extends java.lang.annotation.Annotation> annotationClass)

getConstructorWithAnnotationPreference

public static java.lang.reflect.Constructor<?> getConstructorWithAnnotationPreference(java.lang.Class<?> source,
                                                                                      java.lang.Class<? extends java.lang.annotation.Annotation> annotationClass)

findAllAnnotations

public static <A extends java.lang.annotation.Annotation> java.util.List<A> findAllAnnotations(java.lang.Class<?> clazz,
                                                                                               java.lang.Class<A> annotationType)

Collects all instances of a specific annotation type from a class, its superclass hierarchy, and implemented interfaces. This method recursively traverses the inheritance chain and interface hierarchy, collecting declared annotations of the specified type from each level. Only directly declared annotations are collected (not inherited ones). Duplicate annotations from the same class/interface are avoided through cycle detection.

Type Parameters:

A - The annotation type to collect

Parameters:

clazz - The class to start the search from

annotationType - The class object representing the annotation type to collect

Returns:

A list containing all found annotations of the specified type, ordered by traversal: starting class, then superclasses (bottom-up), then interfaces at each level. Returns an empty list if no annotations are found.

Throws:

java.lang.NullPointerException - if clazz or annotationType is null

getConstructors

public static java.util.List<java.lang.reflect.Constructor<?>> getConstructors(java.lang.Class<?> source)

getConstructorWithAnnotationPreference

public static javax.lang.model.element.ExecutableElement getConstructorWithAnnotationPreference(javax.lang.model.element.TypeElement typeElement,
                                                                                                java.lang.Class<? extends java.lang.annotation.Annotation> annotationClass)

filterAnnotatedConstructors

public static java.util.List<javax.lang.model.element.ExecutableElement> filterAnnotatedConstructors(java.util.List<javax.lang.model.element.ExecutableElement> constructorElements,
                                                                                                     java.lang.Class<? extends java.lang.annotation.Annotation> annotationClass)

getConstructors

public static java.util.List<javax.lang.model.element.ExecutableElement> getConstructors(javax.lang.model.element.TypeElement typeElement)

getParametersTypesQualifiedNames

public static java.util.List<java.lang.String> getParametersTypesQualifiedNames(javax.lang.model.element.ExecutableElement element)

getDefaultConstructor

public static java.lang.reflect.Constructor<?> getDefaultConstructor(java.lang.Class<?> targetClass)

Finds the default constructor of a class

Parameters:

targetClass - the class where the constructor is declared

Returns:

the matching constructor

getConstructorFromParameterTypeNames

public static java.lang.reflect.Constructor<?> getConstructorFromParameterTypeNames(java.lang.Class<?> targetClass,
                                                                                    java.util.List<java.lang.String> parameterTypeNames)

Finds a constructor that matches the provided parameter type names. - If parameterTypeNames is null/empty: return the default (no-arg) constructor, whether implicit or explicit. - Otherwise: search only declared constructors. * First, filter by same arity (parameter count). * If exactly one remains, return it. * If several remain, require an exact declared match by resolved types.

Parameters:

targetClass - the class where the constructor is declared

parameterTypeNames - list of parameter type names (e.g., "java.lang.String", "int[]")

Returns:

the matching constructor

getDeclaredMethodFromParameterTypeNames

public static java.lang.reflect.Method getDeclaredMethodFromParameterTypeNames(java.lang.Class<?> targetClass,
                                                                               java.lang.String methodName,
                                                                               java.util.List<java.lang.String> parameterTypeNames)

Finds a declared method by name using your 3-step heuristic: 1) Filter declared methods by name. - If exactly one remains, return it. 2) Else, filter by parameter count == parameterTypeNames.size(). - If exactly one remains, return it. 3) Else, resolve the parameter type names to classes and call getDeclaredMethod(...) for an exact type match. If not found, throw. Notes: - Only declared methods are considered (no inheritance).