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/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
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 * distributed under the License is distributed on an "AS IS" BASIS,
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package org.apache.commons.lang3.reflect;

import java.lang.annotation.Annotation;
import java.lang.reflect.Array;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.lang.reflect.Modifier;
import java.lang.reflect.Type;
import java.lang.reflect.TypeVariable;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Comparator;
import java.util.Iterator;
import java.util.LinkedHashSet;
import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.TreeMap;
import java.util.stream.Collectors;

import org.apache.commons.lang3.ArrayUtils;
import org.apache.commons.lang3.ClassUtils;
import org.apache.commons.lang3.ClassUtils.Interfaces;
import org.apache.commons.lang3.Validate;

import static java.util.stream.Collectors.toList;

/**
 * 

Utility reflection methods focused on {@link Method}s, originally from Commons BeanUtils. * Differences from the BeanUtils version may be noted, especially where similar functionality * already existed within Lang. *

* *

Known Limitations

*

Accessing Public Methods In A Default Access Superclass

*

There is an issue when invoking {@code public} methods contained in a default access superclass on JREs prior to 1.4. * Reflection locates these methods fine and correctly assigns them as {@code public}. * However, an {@link IllegalAccessException} is thrown if the method is invoked.

* *

{@link MethodUtils} contains a workaround for this situation. * It will attempt to call {@link java.lang.reflect.AccessibleObject#setAccessible(boolean)} on this method. * If this call succeeds, then the method can be invoked as normal. * This call will only succeed when the application has sufficient security privileges. * If this call fails then the method may fail.

* * @since 2.5 */ public class MethodUtils { private static final Comparator METHOD_BY_SIGNATURE = Comparator.comparing(Method::toString); /** *

{@link MethodUtils} instances should NOT be constructed in standard programming. * Instead, the class should be used as * {@code MethodUtils.getAccessibleMethod(method)}.

* *

This constructor is {@code public} to permit tools that require a JavaBean * instance to operate.

*/ public MethodUtils() { } /** *

Invokes a named method without parameters.

* *

This method delegates the method search to {@link #getMatchingAccessibleMethod(Class, String, Class[])}.

* *

This is a convenient wrapper for * {@link #invokeMethod(Object object, String methodName, Object[] args, Class[] parameterTypes)}. *

* * @param object invoke method on this object * @param methodName get method with this name * @return The value returned by the invoked method * * @throws NoSuchMethodException if there is no such accessible method * @throws InvocationTargetException wraps an exception thrown by the method invoked * @throws IllegalAccessException if the requested method is not accessible via reflection * * @since 3.4 */ public static Object invokeMethod(final Object object, final String methodName) throws NoSuchMethodException, IllegalAccessException, InvocationTargetException { return invokeMethod(object, methodName, ArrayUtils.EMPTY_OBJECT_ARRAY, null); } /** *

Invokes a named method without parameters.

* *

This is a convenient wrapper for * {@link #invokeMethod(Object object, boolean forceAccess, String methodName, Object[] args, Class[] parameterTypes)}. *

* * @param object invoke method on this object * @param forceAccess force access to invoke method even if it's not accessible * @param methodName get method with this name * @return The value returned by the invoked method * * @throws NoSuchMethodException if there is no such accessible method * @throws InvocationTargetException wraps an exception thrown by the method invoked * @throws IllegalAccessException if the requested method is not accessible via reflection * * @since 3.5 */ public static Object invokeMethod(final Object object, final boolean forceAccess, final String methodName) throws NoSuchMethodException, IllegalAccessException, InvocationTargetException { return invokeMethod(object, forceAccess, methodName, ArrayUtils.EMPTY_OBJECT_ARRAY, null); } /** *

Invokes a named method whose parameter type matches the object type.

* *

This method delegates the method search to {@link #getMatchingAccessibleMethod(Class, String, Class[])}.

* *

This method supports calls to methods taking primitive parameters * via passing in wrapping classes. So, for example, a {@code Boolean} object * would match a {@code boolean} primitive.

* *

This is a convenient wrapper for * {@link #invokeMethod(Object object, String methodName, Object[] args, Class[] parameterTypes)}. *

* * @param object invoke method on this object * @param methodName get method with this name * @param args use these arguments - treat null as empty array * @return The value returned by the invoked method * * @throws NoSuchMethodException if there is no such accessible method * @throws InvocationTargetException wraps an exception thrown by the method invoked * @throws IllegalAccessException if the requested method is not accessible via reflection */ public static Object invokeMethod(final Object object, final String methodName, Object... args) throws NoSuchMethodException, IllegalAccessException, InvocationTargetException { args = ArrayUtils.nullToEmpty(args); final Class[] parameterTypes = ClassUtils.toClass(args); return invokeMethod(object, methodName, args, parameterTypes); } /** *

Invokes a named method whose parameter type matches the object type.

* *

This method supports calls to methods taking primitive parameters * via passing in wrapping classes. So, for example, a {@code Boolean} object * would match a {@code boolean} primitive.

* *

This is a convenient wrapper for * {@link #invokeMethod(Object object, boolean forceAccess, String methodName, Object[] args, Class[] parameterTypes)}. *

* * @param object invoke method on this object * @param forceAccess force access to invoke method even if it's not accessible * @param methodName get method with this name * @param args use these arguments - treat null as empty array * @return The value returned by the invoked method * * @throws NoSuchMethodException if there is no such accessible method * @throws InvocationTargetException wraps an exception thrown by the method invoked * @throws IllegalAccessException if the requested method is not accessible via reflection * * @since 3.5 */ public static Object invokeMethod(final Object object, final boolean forceAccess, final String methodName, Object... args) throws NoSuchMethodException, IllegalAccessException, InvocationTargetException { args = ArrayUtils.nullToEmpty(args); final Class[] parameterTypes = ClassUtils.toClass(args); return invokeMethod(object, forceAccess, methodName, args, parameterTypes); } /** *

Invokes a named method whose parameter type matches the object type.

* *

This method supports calls to methods taking primitive parameters * via passing in wrapping classes. So, for example, a {@code Boolean} object * would match a {@code boolean} primitive.

* * @param object invoke method on this object * @param forceAccess force access to invoke method even if it's not accessible * @param methodName get method with this name * @param args use these arguments - treat null as empty array * @param parameterTypes match these parameters - treat null as empty array * @return The value returned by the invoked method * * @throws NoSuchMethodException if there is no such accessible method * @throws InvocationTargetException wraps an exception thrown by the method invoked * @throws IllegalAccessException if the requested method is not accessible via reflection * @since 3.5 */ public static Object invokeMethod(final Object object, final boolean forceAccess, final String methodName, Object[] args, Class[] parameterTypes) throws NoSuchMethodException, IllegalAccessException, InvocationTargetException { parameterTypes = ArrayUtils.nullToEmpty(parameterTypes); args = ArrayUtils.nullToEmpty(args); final String messagePrefix; Method method = null; if (forceAccess) { messagePrefix = "No such method: "; method = getMatchingMethod(object.getClass(), methodName, parameterTypes); if (method != null && !method.isAccessible()) { method.setAccessible(true); } } else { messagePrefix = "No such accessible method: "; method = getMatchingAccessibleMethod(object.getClass(), methodName, parameterTypes); } if (method == null) { throw new NoSuchMethodException(messagePrefix + methodName + "() on object: " + object.getClass().getName()); } args = toVarArgs(method, args); return method.invoke(object, args); } /** *

Invokes a named method whose parameter type matches the object type.

* *

This method delegates the method search to {@link #getMatchingAccessibleMethod(Class, String, Class[])}.

* *

This method supports calls to methods taking primitive parameters * via passing in wrapping classes. So, for example, a {@code Boolean} object * would match a {@code boolean} primitive.

* * @param object invoke method on this object * @param methodName get method with this name * @param args use these arguments - treat null as empty array * @param parameterTypes match these parameters - treat null as empty array * @return The value returned by the invoked method * * @throws NoSuchMethodException if there is no such accessible method * @throws InvocationTargetException wraps an exception thrown by the method invoked * @throws IllegalAccessException if the requested method is not accessible via reflection */ public static Object invokeMethod(final Object object, final String methodName, final Object[] args, final Class[] parameterTypes) throws NoSuchMethodException, IllegalAccessException, InvocationTargetException { return invokeMethod(object, false, methodName, args, parameterTypes); } /** *

Invokes a method whose parameter types match exactly the object * types.

* *

This uses reflection to invoke the method obtained from a call to * {@link #getAccessibleMethod}(Class, String, Class[])}.

* * @param object invoke method on this object * @param methodName get method with this name * @return The value returned by the invoked method * * @throws NoSuchMethodException if there is no such accessible method * @throws InvocationTargetException wraps an exception thrown by the * method invoked * @throws IllegalAccessException if the requested method is not accessible * via reflection * * @since 3.4 */ public static Object invokeExactMethod(final Object object, final String methodName) throws NoSuchMethodException, IllegalAccessException, InvocationTargetException { return invokeExactMethod(object, methodName, ArrayUtils.EMPTY_OBJECT_ARRAY, null); } /** *

Invokes a method with no parameters.

* *

This uses reflection to invoke the method obtained from a call to * {@link #getAccessibleMethod}(Class, String, Class[])}.

* * @param object invoke method on this object * @param methodName get method with this name * @param args use these arguments - treat null as empty array * @return The value returned by the invoked method * * @throws NoSuchMethodException if there is no such accessible method * @throws InvocationTargetException wraps an exception thrown by the * method invoked * @throws IllegalAccessException if the requested method is not accessible * via reflection */ public static Object invokeExactMethod(final Object object, final String methodName, Object... args) throws NoSuchMethodException, IllegalAccessException, InvocationTargetException { args = ArrayUtils.nullToEmpty(args); final Class[] parameterTypes = ClassUtils.toClass(args); return invokeExactMethod(object, methodName, args, parameterTypes); } /** *

Invokes a method whose parameter types match exactly the parameter * types given.

* *

This uses reflection to invoke the method obtained from a call to * {@link #getAccessibleMethod(Class, String, Class[])}.

* * @param object invoke method on this object * @param methodName get method with this name * @param args use these arguments - treat null as empty array * @param parameterTypes match these parameters - treat {@code null} as empty array * @return The value returned by the invoked method * * @throws NoSuchMethodException if there is no such accessible method * @throws InvocationTargetException wraps an exception thrown by the * method invoked * @throws IllegalAccessException if the requested method is not accessible * via reflection */ public static Object invokeExactMethod(final Object object, final String methodName, Object[] args, Class[] parameterTypes) throws NoSuchMethodException, IllegalAccessException, InvocationTargetException { args = ArrayUtils.nullToEmpty(args); parameterTypes = ArrayUtils.nullToEmpty(parameterTypes); final Method method = getAccessibleMethod(object.getClass(), methodName, parameterTypes); if (method == null) { throw new NoSuchMethodException("No such accessible method: " + methodName + "() on object: " + object.getClass().getName()); } return method.invoke(object, args); } /** *

Invokes a {@code static} method whose parameter types match exactly the parameter * types given.

* *

This uses reflection to invoke the method obtained from a call to * {@link #getAccessibleMethod(Class, String, Class[])}.

* * @param cls invoke static method on this class * @param methodName get method with this name * @param args use these arguments - treat {@code null} as empty array * @param parameterTypes match these parameters - treat {@code null} as empty array * @return The value returned by the invoked method * * @throws NoSuchMethodException if there is no such accessible method * @throws InvocationTargetException wraps an exception thrown by the * method invoked * @throws IllegalAccessException if the requested method is not accessible * via reflection */ public static Object invokeExactStaticMethod(final Class cls, final String methodName, Object[] args, Class[] parameterTypes) throws NoSuchMethodException, IllegalAccessException, InvocationTargetException { args = ArrayUtils.nullToEmpty(args); parameterTypes = ArrayUtils.nullToEmpty(parameterTypes); final Method method = getAccessibleMethod(cls, methodName, parameterTypes); if (method == null) { throw new NoSuchMethodException("No such accessible method: " + methodName + "() on class: " + cls.getName()); } return method.invoke(null, args); } /** *

Invokes a named {@code static} method whose parameter type matches the object type.

* *

This method delegates the method search to {@link #getMatchingAccessibleMethod(Class, String, Class[])}.

* *

This method supports calls to methods taking primitive parameters * via passing in wrapping classes. So, for example, a {@code Boolean} class * would match a {@code boolean} primitive.

* *

This is a convenient wrapper for * {@link #invokeStaticMethod(Class, String, Object[], Class[])}. *

* * @param cls invoke static method on this class * @param methodName get method with this name * @param args use these arguments - treat {@code null} as empty array * @return The value returned by the invoked method * * @throws NoSuchMethodException if there is no such accessible method * @throws InvocationTargetException wraps an exception thrown by the * method invoked * @throws IllegalAccessException if the requested method is not accessible * via reflection */ public static Object invokeStaticMethod(final Class cls, final String methodName, Object... args) throws NoSuchMethodException, IllegalAccessException, InvocationTargetException { args = ArrayUtils.nullToEmpty(args); final Class[] parameterTypes = ClassUtils.toClass(args); return invokeStaticMethod(cls, methodName, args, parameterTypes); } /** *

Invokes a named {@code static} method whose parameter type matches the object type.

* *

This method delegates the method search to {@link #getMatchingAccessibleMethod(Class, String, Class[])}.

* *

This method supports calls to methods taking primitive parameters * via passing in wrapping classes. So, for example, a {@code Boolean} class * would match a {@code boolean} primitive.

* * * @param cls invoke static method on this class * @param methodName get method with this name * @param args use these arguments - treat {@code null} as empty array * @param parameterTypes match these parameters - treat {@code null} as empty array * @return The value returned by the invoked method * * @throws NoSuchMethodException if there is no such accessible method * @throws InvocationTargetException wraps an exception thrown by the * method invoked * @throws IllegalAccessException if the requested method is not accessible * via reflection */ public static Object invokeStaticMethod(final Class cls, final String methodName, Object[] args, Class[] parameterTypes) throws NoSuchMethodException, IllegalAccessException, InvocationTargetException { args = ArrayUtils.nullToEmpty(args); parameterTypes = ArrayUtils.nullToEmpty(parameterTypes); final Method method = getMatchingAccessibleMethod(cls, methodName, parameterTypes); if (method == null) { throw new NoSuchMethodException("No such accessible method: " + methodName + "() on class: " + cls.getName()); } args = toVarArgs(method, args); return method.invoke(null, args); } private static Object[] toVarArgs(final Method method, Object[] args) { if (method.isVarArgs()) { final Class[] methodParameterTypes = method.getParameterTypes(); args = getVarArgs(args, methodParameterTypes); } return args; } /** *

Given an arguments array passed to a varargs method, return an array of arguments in the canonical form, * i.e. an array with the declared number of parameters, and whose last parameter is an array of the varargs type. *

* * @param args the array of arguments passed to the varags method * @param methodParameterTypes the declared array of method parameter types * @return an array of the variadic arguments passed to the method * @since 3.5 */ static Object[] getVarArgs(final Object[] args, final Class[] methodParameterTypes) { if (args.length == methodParameterTypes.length && (args[args.length - 1] == null || args[args.length - 1].getClass().equals(methodParameterTypes[methodParameterTypes.length - 1]))) { // The args array is already in the canonical form for the method. return args; } // Construct a new array matching the method's declared parameter types. final Object[] newArgs = new Object[methodParameterTypes.length]; // Copy the normal (non-varargs) parameters System.arraycopy(args, 0, newArgs, 0, methodParameterTypes.length - 1); // Construct a new array for the variadic parameters final Class varArgComponentType = methodParameterTypes[methodParameterTypes.length - 1].getComponentType(); final int varArgLength = args.length - methodParameterTypes.length + 1; Object varArgsArray = Array.newInstance(ClassUtils.primitiveToWrapper(varArgComponentType), varArgLength); // Copy the variadic arguments into the varargs array. System.arraycopy(args, methodParameterTypes.length - 1, varArgsArray, 0, varArgLength); if (varArgComponentType.isPrimitive()) { // unbox from wrapper type to primitive type varArgsArray = ArrayUtils.toPrimitive(varArgsArray); } // Store the varargs array in the last position of the array to return newArgs[methodParameterTypes.length - 1] = varArgsArray; // Return the canonical varargs array. return newArgs; } /** *

Invokes a {@code static} method whose parameter types match exactly the object * types.

* *

This uses reflection to invoke the method obtained from a call to * {@link #getAccessibleMethod(Class, String, Class[])}.

* * @param cls invoke static method on this class * @param methodName get method with this name * @param args use these arguments - treat {@code null} as empty array * @return The value returned by the invoked method * * @throws NoSuchMethodException if there is no such accessible method * @throws InvocationTargetException wraps an exception thrown by the * method invoked * @throws IllegalAccessException if the requested method is not accessible * via reflection */ public static Object invokeExactStaticMethod(final Class cls, final String methodName, Object... args) throws NoSuchMethodException, IllegalAccessException, InvocationTargetException { args = ArrayUtils.nullToEmpty(args); final Class[] parameterTypes = ClassUtils.toClass(args); return invokeExactStaticMethod(cls, methodName, args, parameterTypes); } /** *

Returns an accessible method (that is, one that can be invoked via * reflection) with given name and parameters. If no such method * can be found, return {@code null}. * This is just a convenience wrapper for * {@link #getAccessibleMethod(Method)}.

* * @param cls get method from this class * @param methodName get method with this name * @param parameterTypes with these parameters types * @return The accessible method */ public static Method getAccessibleMethod(final Class cls, final String methodName, final Class... parameterTypes) { try { return getAccessibleMethod(cls.getMethod(methodName, parameterTypes)); } catch (final NoSuchMethodException e) { return null; } } /** *

Returns an accessible method (that is, one that can be invoked via * reflection) that implements the specified Method. If no such method * can be found, return {@code null}.

* * @param method The method that we wish to call * @return The accessible method */ public static Method getAccessibleMethod(Method method) { if (!MemberUtils.isAccessible(method)) { return null; } // If the declaring class is public, we are done final Class cls = method.getDeclaringClass(); if (Modifier.isPublic(cls.getModifiers())) { return method; } final String methodName = method.getName(); final Class[] parameterTypes = method.getParameterTypes(); // Check the implemented interfaces and subinterfaces method = getAccessibleMethodFromInterfaceNest(cls, methodName, parameterTypes); // Check the superclass chain if (method == null) { method = getAccessibleMethodFromSuperclass(cls, methodName, parameterTypes); } return method; } /** *

Returns an accessible method (that is, one that can be invoked via * reflection) by scanning through the superclasses. If no such method * can be found, return {@code null}.

* * @param cls Class to be checked * @param methodName Method name of the method we wish to call * @param parameterTypes The parameter type signatures * @return the accessible method or {@code null} if not found */ private static Method getAccessibleMethodFromSuperclass(final Class cls, final String methodName, final Class... parameterTypes) { Class parentClass = cls.getSuperclass(); while (parentClass != null) { if (Modifier.isPublic(parentClass.getModifiers())) { try { return parentClass.getMethod(methodName, parameterTypes); } catch (final NoSuchMethodException e) { return null; } } parentClass = parentClass.getSuperclass(); } return null; } /** *

Returns an accessible method (that is, one that can be invoked via * reflection) that implements the specified method, by scanning through * all implemented interfaces and subinterfaces. If no such method * can be found, return {@code null}.

* *

There isn't any good reason why this method must be {@code private}. * It is because there doesn't seem any reason why other classes should * call this rather than the higher level methods.

* * @param cls Parent class for the interfaces to be checked * @param methodName Method name of the method we wish to call * @param parameterTypes The parameter type signatures * @return the accessible method or {@code null} if not found */ private static Method getAccessibleMethodFromInterfaceNest(Class cls, final String methodName, final Class... parameterTypes) { // Search up the superclass chain for (; cls != null; cls = cls.getSuperclass()) { // Check the implemented interfaces of the parent class final Class[] interfaces = cls.getInterfaces(); for (final Class anInterface : interfaces) { // Is this interface public? if (!Modifier.isPublic(anInterface.getModifiers())) { continue; } // Does the method exist on this interface? try { return anInterface.getDeclaredMethod(methodName, parameterTypes); } catch (final NoSuchMethodException e) { // NOPMD /* * Swallow, if no method is found after the loop then this * method returns null. */ } // Recursively check our parent interfaces final Method method = getAccessibleMethodFromInterfaceNest(anInterface, methodName, parameterTypes); if (method != null) { return method; } } } return null; } /** *

Finds an accessible method that matches the given name and has compatible parameters. * Compatible parameters mean that every method parameter is assignable from * the given parameters. * In other words, it finds a method with the given name * that will take the parameters given.

* *

This method is used by * {@link * #invokeMethod(Object object, String methodName, Object[] args, Class[] parameterTypes)}. *

* *

This method can match primitive parameter by passing in wrapper classes. * For example, a {@code Boolean} will match a primitive {@code boolean} * parameter. *

* * @param cls find method in this class * @param methodName find method with this name * @param parameterTypes find method with most compatible parameters * @return The accessible method */ public static Method getMatchingAccessibleMethod(final Class cls, final String methodName, final Class... parameterTypes) { try { final Method method = cls.getMethod(methodName, parameterTypes); MemberUtils.setAccessibleWorkaround(method); return method; } catch (final NoSuchMethodException e) { // NOPMD - Swallow the exception } // search through all methods final Method[] methods = cls.getMethods(); final List matchingMethods = new ArrayList<>(); for (final Method method : methods) { // compare name and parameters if (method.getName().equals(methodName) && MemberUtils.isMatchingMethod(method, parameterTypes)) { matchingMethods.add (method); } } // Sort methods by signature to force deterministic result matchingMethods.sort(METHOD_BY_SIGNATURE); Method bestMatch = null; for (final Method method : matchingMethods) { // get accessible version of method final Method accessibleMethod = getAccessibleMethod(method); if (accessibleMethod != null && (bestMatch == null || MemberUtils.compareMethodFit( accessibleMethod, bestMatch, parameterTypes) < 0)) { bestMatch = accessibleMethod; } } if (bestMatch != null) { MemberUtils.setAccessibleWorkaround(bestMatch); } if (bestMatch != null && bestMatch.isVarArgs() && bestMatch.getParameterTypes().length > 0 && parameterTypes.length > 0) { final Class[] methodParameterTypes = bestMatch.getParameterTypes(); final Class methodParameterComponentType = methodParameterTypes[methodParameterTypes.length - 1].getComponentType(); final String methodParameterComponentTypeName = ClassUtils.primitiveToWrapper(methodParameterComponentType).getName(); final Class lastParameterType = parameterTypes[parameterTypes.length - 1]; final String parameterTypeName = (lastParameterType==null) ? null : lastParameterType.getName(); final String parameterTypeSuperClassName = (lastParameterType==null) ? null : lastParameterType.getSuperclass().getName(); if (parameterTypeName!= null && parameterTypeSuperClassName != null && !methodParameterComponentTypeName.equals(parameterTypeName) && !methodParameterComponentTypeName.equals(parameterTypeSuperClassName)) { return null; } } return bestMatch; } /** *

Retrieves a method whether or not it's accessible. If no such method * can be found, return {@code null}.

* @param cls The class that will be subjected to the method search * @param methodName The method that we wish to call * @param parameterTypes Argument class types * @return The method * * @since 3.5 */ public static Method getMatchingMethod(final Class cls, final String methodName, final Class... parameterTypes) { Validate.notNull(cls, "cls"); Validate.notEmpty(methodName, "methodName"); final List methods = Arrays.stream(cls.getDeclaredMethods()) .filter(method -> method.getName().equals(methodName)) .collect(toList()); ClassUtils.getAllSuperclasses(cls).stream() .map(Class::getDeclaredMethods) .flatMap(Arrays::stream) .filter(method -> method.getName().equals(methodName)) .forEach(methods::add); for (final Method method : methods) { if (Arrays.deepEquals(method.getParameterTypes(), parameterTypes)) { return method; } } final TreeMap> candidates = new TreeMap<>(); methods.stream() .filter(method -> ClassUtils.isAssignable(parameterTypes, method.getParameterTypes(), true)) .forEach(method -> { final int distance = distance(parameterTypes, method.getParameterTypes()); final List candidatesAtDistance = candidates.computeIfAbsent(distance, k -> new ArrayList<>()); candidatesAtDistance.add(method); }); if (candidates.isEmpty()) { return null; } final List bestCandidates = candidates.values().iterator().next(); if (bestCandidates.size() == 1) { return bestCandidates.get(0); } throw new IllegalStateException( String.format("Found multiple candidates for method %s on class %s : %s", methodName + Arrays.stream(parameterTypes).map(String::valueOf).collect(Collectors.joining(",", "(", ")")), cls.getName(), bestCandidates.stream().map(Method::toString).collect(Collectors.joining(",", "[", "]"))) ); } /** *

Returns the aggregate number of inheritance hops between assignable argument class types. Returns -1 * if the arguments aren't assignable. Fills a specific purpose for getMatchingMethod and is not generalized.

* @param fromClassArray the Class array to calculate the distance from. * @param toClassArray the Class array to calculate the distance to. * @return the aggregate number of inheritance hops between assignable argument class types. */ private static int distance(final Class[] fromClassArray, final Class[] toClassArray) { int answer = 0; if (!ClassUtils.isAssignable(fromClassArray, toClassArray, true)) { return -1; } for (int offset = 0; offset < fromClassArray.length; offset++) { // Note InheritanceUtils.distance() uses different scoring system. final Class aClass = fromClassArray[offset]; final Class toClass = toClassArray[offset]; if (aClass == null || aClass.equals(toClass)) { continue; } else if (ClassUtils.isAssignable(aClass, toClass, true) && !ClassUtils.isAssignable(aClass, toClass, false)) { answer++; } else { answer = answer + 2; } } return answer; } /** * Gets the hierarchy of overridden methods down to {@code result} respecting generics. * @param method lowest to consider * @param interfacesBehavior whether to search interfaces, {@code null} {@code implies} false * @return Set<Method> in ascending order from sub- to superclass * @throws NullPointerException if the specified method is {@code null} * @since 3.2 */ public static Set getOverrideHierarchy(final Method method, final Interfaces interfacesBehavior) { Validate.notNull(method); final Set result = new LinkedHashSet<>(); result.add(method); final Class[] parameterTypes = method.getParameterTypes(); final Class declaringClass = method.getDeclaringClass(); final Iterator> hierarchy = ClassUtils.hierarchy(declaringClass, interfacesBehavior).iterator(); //skip the declaring class :P hierarchy.next(); hierarchyTraversal: while (hierarchy.hasNext()) { final Class c = hierarchy.next(); final Method m = getMatchingAccessibleMethod(c, method.getName(), parameterTypes); if (m == null) { continue; } if (Arrays.equals(m.getParameterTypes(), parameterTypes)) { // matches without generics result.add(m); continue; } // necessary to get arguments every time in the case that we are including interfaces final Map, Type> typeArguments = TypeUtils.getTypeArguments(declaringClass, m.getDeclaringClass()); for (int i = 0; i < parameterTypes.length; i++) { final Type childType = TypeUtils.unrollVariables(typeArguments, method.getGenericParameterTypes()[i]); final Type parentType = TypeUtils.unrollVariables(typeArguments, m.getGenericParameterTypes()[i]); if (!TypeUtils.equals(childType, parentType)) { continue hierarchyTraversal; } } result.add(m); } return result; } /** * Gets all class level public methods of the given class that are annotated with the given annotation. * @param cls * the {@link Class} to query * @param annotationCls * the {@link java.lang.annotation.Annotation} that must be present on a method to be matched * @return an array of Methods (possibly empty). * @throws NullPointerException if the class or annotation are {@code null} * @since 3.4 */ public static Method[] getMethodsWithAnnotation(final Class cls, final Class annotationCls) { return getMethodsWithAnnotation(cls, annotationCls, false, false); } /** * Gets all class level public methods of the given class that are annotated with the given annotation. * @param cls * the {@link Class} to query * @param annotationCls * the {@link Annotation} that must be present on a method to be matched * @return a list of Methods (possibly empty). * @throws IllegalArgumentException * if the class or annotation are {@code null} * @since 3.4 */ public static List getMethodsListWithAnnotation(final Class cls, final Class annotationCls) { return getMethodsListWithAnnotation(cls, annotationCls, false, false); } /** * Gets all methods of the given class that are annotated with the given annotation. * @param cls * the {@link Class} to query * @param annotationCls * the {@link java.lang.annotation.Annotation} that must be present on a method to be matched * @param searchSupers * determines if a lookup in the entire inheritance hierarchy of the given class should be performed * @param ignoreAccess * determines if non public methods should be considered * @return an array of Methods (possibly empty). * @throws NullPointerException if the class or annotation are {@code null} * @since 3.6 */ public static Method[] getMethodsWithAnnotation(final Class cls, final Class annotationCls, final boolean searchSupers, final boolean ignoreAccess) { final List annotatedMethodsList = getMethodsListWithAnnotation(cls, annotationCls, searchSupers, ignoreAccess); return annotatedMethodsList.toArray(ArrayUtils.EMPTY_METHOD_ARRAY); } /** * Gets all methods of the given class that are annotated with the given annotation. * @param cls * the {@link Class} to query * @param annotationCls * the {@link Annotation} that must be present on a method to be matched * @param searchSupers * determines if a lookup in the entire inheritance hierarchy of the given class should be performed * @param ignoreAccess * determines if non public methods should be considered * @return a list of Methods (possibly empty). * @throws NullPointerException if either the class or annotation class is {@code null} * @since 3.6 */ public static List getMethodsListWithAnnotation(final Class cls, final Class annotationCls, final boolean searchSupers, final boolean ignoreAccess) { Validate.notNull(cls, "cls"); Validate.notNull(annotationCls, "annotationCls"); final List> classes = (searchSupers ? getAllSuperclassesAndInterfaces(cls) : new ArrayList<>()); classes.add(0, cls); final List annotatedMethods = new ArrayList<>(); for (final Class acls : classes) { final Method[] methods = (ignoreAccess ? acls.getDeclaredMethods() : acls.getMethods()); for (final Method method : methods) { if (method.getAnnotation(annotationCls) != null) { annotatedMethods.add(method); } } } return annotatedMethods; } /** *

Gets the annotation object with the given annotation type that is present on the given method * or optionally on any equivalent method in super classes and interfaces. Returns null if the annotation * type was not present.

* *

Stops searching for an annotation once the first annotation of the specified type has been * found. Additional annotations of the specified type will be silently ignored.

* @param * the annotation type * @param method * the {@link Method} to query * @param annotationCls * the {@link Annotation} to check if is present on the method * @param searchSupers * determines if a lookup in the entire inheritance hierarchy of the given class is performed * if the annotation was not directly present * @param ignoreAccess * determines if underlying method has to be accessible * @return the first matching annotation, or {@code null} if not found * @throws NullPointerException if either the method or annotation class is {@code null} * @since 3.6 */ public static A getAnnotation(final Method method, final Class annotationCls, final boolean searchSupers, final boolean ignoreAccess) { Validate.notNull(method, "method"); Validate.notNull(annotationCls, "annotationCls"); if (!ignoreAccess && !MemberUtils.isAccessible(method)) { return null; } A annotation = method.getAnnotation(annotationCls); if (annotation == null && searchSupers) { final Class mcls = method.getDeclaringClass(); final List> classes = getAllSuperclassesAndInterfaces(mcls); for (final Class acls : classes) { final Method equivalentMethod = (ignoreAccess ? MethodUtils.getMatchingMethod(acls, method.getName(), method.getParameterTypes()) : MethodUtils.getMatchingAccessibleMethod(acls, method.getName(), method.getParameterTypes())); if (equivalentMethod != null) { annotation = equivalentMethod.getAnnotation(annotationCls); if (annotation != null) { break; } } } } return annotation; } /** *

Gets a combination of {@link ClassUtils#getAllSuperclasses(Class)} and * {@link ClassUtils#getAllInterfaces(Class)}, one from superclasses, one * from interfaces, and so on in a breadth first way.

* * @param cls the class to look up, may be {@code null} * @return the combined {@code List} of superclasses and interfaces in order * going up from this one * {@code null} if null input */ private static List> getAllSuperclassesAndInterfaces(final Class cls) { if (cls == null) { return null; } final List> allSuperClassesAndInterfaces = new ArrayList<>(); final List> allSuperclasses = ClassUtils.getAllSuperclasses(cls); int superClassIndex = 0; final List> allInterfaces = ClassUtils.getAllInterfaces(cls); int interfaceIndex = 0; while (interfaceIndex < allInterfaces.size() || superClassIndex < allSuperclasses.size()) { final Class acls; if (interfaceIndex >= allInterfaces.size()) { acls = allSuperclasses.get(superClassIndex++); } else if ((superClassIndex >= allSuperclasses.size()) || (interfaceIndex < superClassIndex) || !(superClassIndex < interfaceIndex)) { acls = allInterfaces.get(interfaceIndex++); } else { acls = allSuperclasses.get(superClassIndex++); } allSuperClassesAndInterfaces.add(acls); } return allSuperClassesAndInterfaces; } }




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