package com.fasterxml.jackson.databind.introspect;

import java.lang.annotation.Annotation;
import java.lang.reflect.AnnotatedElement;
import java.lang.reflect.Constructor;
import java.lang.reflect.Method;
import java.lang.reflect.Modifier;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;

import com.fasterxml.jackson.databind.AnnotationIntrospector;
import com.fasterxml.jackson.databind.JavaType;
import com.fasterxml.jackson.databind.introspect.AnnotatedClass.Creators;
import com.fasterxml.jackson.databind.util.ClassUtil;

Helper class used to contain details of how Creators (annotated constructors and static methods) are discovered to be accessed by and via AnnotatedClass.
Since:2.9
/** * Helper class used to contain details of how Creators (annotated constructors * and static methods) are discovered to be accessed by and via {@link AnnotatedClass}. * * @since 2.9 */
final class AnnotatedCreatorCollector extends CollectorBase { // // // Configuration private final TypeResolutionContext _typeContext;
Since:2.11
/** * @since 2.11 */
private final boolean _collectAnnotations; // // // Collected state private AnnotatedConstructor _defaultConstructor; AnnotatedCreatorCollector(AnnotationIntrospector intr, TypeResolutionContext tc, boolean collectAnnotations) { super(intr); _typeContext = tc; _collectAnnotations = collectAnnotations; } public static Creators collectCreators(AnnotationIntrospector intr, TypeResolutionContext tc, JavaType type, Class<?> primaryMixIn, boolean collectAnnotations) { final boolean checkClassAnnotations = (intr != null) && !ClassUtil.isJDKClass(type.getRawClass()); // Constructor also always members of resolved class, parent == resolution context return new AnnotatedCreatorCollector(intr, tc, checkClassAnnotations) .collect(type, primaryMixIn); } Creators collect(JavaType type, Class<?> primaryMixIn) { // 30-Apr-2016, tatu: [databind#1215]: Actually, while true, this does // NOT apply to context since sub-class may have type bindings // TypeResolutionContext typeContext = new TypeResolutionContext.Basic(_typeFactory, _type.getBindings()); List<AnnotatedConstructor> constructors = _findPotentialConstructors(type, primaryMixIn); List<AnnotatedMethod> factories = _findPotentialFactories(type, primaryMixIn); /* And then... let's remove all constructors that are deemed * ignorable after all annotations have been properly collapsed. */ // AnnotationIntrospector is null if annotations not enabled; if so, can skip: if (_collectAnnotations) { if (_defaultConstructor != null) { if (_intr.hasIgnoreMarker(_defaultConstructor)) { _defaultConstructor = null; } } // count down to allow safe removal for (int i = constructors.size(); --i >= 0; ) { if (_intr.hasIgnoreMarker(constructors.get(i))) { constructors.remove(i); } } for (int i = factories.size(); --i >= 0; ) { if (_intr.hasIgnoreMarker(factories.get(i))) { factories.remove(i); } } } return new AnnotatedClass.Creators(_defaultConstructor, constructors, factories); }
Helper method for locating constructors (and matching mix-in overrides) we might want to use; this is needed in order to mix information between the two and construct resulting AnnotatedConstructors
/** * Helper method for locating constructors (and matching mix-in overrides) * we might want to use; this is needed in order to mix information between * the two and construct resulting {@link AnnotatedConstructor}s */
private List<AnnotatedConstructor> _findPotentialConstructors(JavaType type, Class<?> primaryMixIn) { ClassUtil.Ctor defaultCtor = null; List<ClassUtil.Ctor> ctors = null; // 18-Jun-2016, tatu: Enum constructors will never be useful (unlike // possibly static factory methods); but they can be royal PITA // due to some oddities by JVM; see: // [https://github.com/FasterXML/jackson-module-parameter-names/issues/35] // for more. So, let's just skip them. if (!type.isEnumType()) { ClassUtil.Ctor[] declaredCtors = ClassUtil.getConstructors(type.getRawClass()); for (ClassUtil.Ctor ctor : declaredCtors) { if (!isIncludableConstructor(ctor.getConstructor())) { continue; } if (ctor.getParamCount() == 0) { defaultCtor = ctor; } else { if (ctors == null) { ctors = new ArrayList<>(); } ctors.add(ctor); } } } List<AnnotatedConstructor> result; int ctorCount; if (ctors == null) { result = Collections.emptyList(); // Nothing found? Short-circuit if (defaultCtor == null) { return result; } ctorCount = 0; } else { ctorCount = ctors.size(); result = new ArrayList<>(ctorCount); for (int i = 0; i < ctorCount; ++i) { result.add(null); } } // so far so good; but do we also need to find mix-ins overrides? if (primaryMixIn != null) { MemberKey[] ctorKeys = null; for (ClassUtil.Ctor mixinCtor : ClassUtil.getConstructors(primaryMixIn)) { if (mixinCtor.getParamCount() == 0) { if (defaultCtor != null) { _defaultConstructor = constructDefaultConstructor(defaultCtor, mixinCtor); defaultCtor = null; } continue; } if (ctors != null) { if (ctorKeys == null) { ctorKeys = new MemberKey[ctorCount]; for (int i = 0; i < ctorCount; ++i) { ctorKeys[i] = new MemberKey(ctors.get(i).getConstructor()); } } MemberKey key = new MemberKey(mixinCtor.getConstructor()); for (int i = 0; i < ctorCount; ++i) { if (key.equals(ctorKeys[i])) { result.set(i, constructNonDefaultConstructor(ctors.get(i), mixinCtor)); break; } } } } } // Ok: anything within mix-ins has been resolved; anything remaining we must resolve if (defaultCtor != null) { _defaultConstructor = constructDefaultConstructor(defaultCtor, null); } for (int i = 0; i < ctorCount; ++i) { AnnotatedConstructor ctor = result.get(i); if (ctor == null) { result.set(i, constructNonDefaultConstructor(ctors.get(i), null)); } } return result; } private List<AnnotatedMethod> _findPotentialFactories(JavaType type, Class<?> primaryMixIn) { List<Method> candidates = null; // First find all potentially relevant static methods for (Method m : ClassUtil.getClassMethods(type.getRawClass())) { if (!Modifier.isStatic(m.getModifiers())) { continue; } // all factory methods are fine: //int argCount = m.getParameterTypes().length; if (candidates == null) { candidates = new ArrayList<>(); } candidates.add(m); } // and then locate mix-ins, if any if (candidates == null) { return Collections.emptyList(); } int factoryCount = candidates.size(); List<AnnotatedMethod> result = new ArrayList<>(factoryCount); for (int i = 0; i < factoryCount; ++i) { result.add(null); } // so far so good; but do we also need to find mix-ins overrides? if (primaryMixIn != null) { MemberKey[] methodKeys = null; for (Method mixinFactory : primaryMixIn.getDeclaredMethods()) { if (!Modifier.isStatic(mixinFactory.getModifiers())) { continue; } if (methodKeys == null) { methodKeys = new MemberKey[factoryCount]; for (int i = 0; i < factoryCount; ++i) { methodKeys[i] = new MemberKey(candidates.get(i)); } } MemberKey key = new MemberKey(mixinFactory); for (int i = 0; i < factoryCount; ++i) { if (key.equals(methodKeys[i])) { result.set(i, constructFactoryCreator(candidates.get(i), mixinFactory)); break; } } } } // Ok: anything within mix-ins has been resolved; anything remaining we must resolve for (int i = 0; i < factoryCount; ++i) { AnnotatedMethod factory = result.get(i); if (factory == null) { result.set(i, constructFactoryCreator(candidates.get(i), null)); } } return result; } protected AnnotatedConstructor constructDefaultConstructor(ClassUtil.Ctor ctor, ClassUtil.Ctor mixin) { return new AnnotatedConstructor(_typeContext, ctor.getConstructor(), collectAnnotations(ctor, mixin), // 16-Jun-2019, tatu: default is zero-args, so can't have parameter annotations NO_ANNOTATION_MAPS); } protected AnnotatedConstructor constructNonDefaultConstructor(ClassUtil.Ctor ctor, ClassUtil.Ctor mixin) { final int paramCount = ctor.getParamCount(); if (_intr == null) { // when annotation processing is disabled return new AnnotatedConstructor(_typeContext, ctor.getConstructor(), _emptyAnnotationMap(), _emptyAnnotationMaps(paramCount)); } /* Looks like JDK has discrepancy, whereas annotations for implicit 'this' * (for non-static inner classes) are NOT included, but type is? * Strange, sounds like a bug. Alas, we can't really fix that... */ if (paramCount == 0) { // no-arg default constructors, can simplify slightly return new AnnotatedConstructor(_typeContext, ctor.getConstructor(), collectAnnotations(ctor, mixin), NO_ANNOTATION_MAPS); } // Also: enum value constructors AnnotationMap[] resolvedAnnotations; Annotation[][] paramAnns = ctor.getParameterAnnotations(); if (paramCount != paramAnns.length) { // Limits of the work-around (to avoid hiding real errors): // first, only applicable for member classes and then either: resolvedAnnotations = null; Class<?> dc = ctor.getDeclaringClass(); // (a) is enum, which have two extra hidden params (name, index) if (ClassUtil.isEnumType(dc) && (paramCount == paramAnns.length + 2)) { Annotation[][] old = paramAnns; paramAnns = new Annotation[old.length+2][]; System.arraycopy(old, 0, paramAnns, 2, old.length); resolvedAnnotations = collectAnnotations(paramAnns, null); } else if (dc.isMemberClass()) { // (b) non-static inner classes, get implicit 'this' for parameter, not annotation if (paramCount == (paramAnns.length + 1)) { // hack attack: prepend a null entry to make things match Annotation[][] old = paramAnns; paramAnns = new Annotation[old.length+1][]; System.arraycopy(old, 0, paramAnns, 1, old.length); paramAnns[0] = NO_ANNOTATIONS; resolvedAnnotations = collectAnnotations(paramAnns, null); } } if (resolvedAnnotations == null) { throw new IllegalStateException(String.format( "Internal error: constructor for %s has mismatch: %d parameters; %d sets of annotations", ctor.getDeclaringClass().getName(), paramCount, paramAnns.length)); } } else { resolvedAnnotations = collectAnnotations(paramAnns, (mixin == null) ? null : mixin.getParameterAnnotations()); } return new AnnotatedConstructor(_typeContext, ctor.getConstructor(), collectAnnotations(ctor, mixin), resolvedAnnotations); } protected AnnotatedMethod constructFactoryCreator(Method m, Method mixin) { final int paramCount = m.getParameterTypes().length; if (_intr == null) { // when annotation processing is disabled return new AnnotatedMethod(_typeContext, m, _emptyAnnotationMap(), _emptyAnnotationMaps(paramCount)); } if (paramCount == 0) { // common enough we can slightly optimize return new AnnotatedMethod(_typeContext, m, collectAnnotations(m, mixin), NO_ANNOTATION_MAPS); } return new AnnotatedMethod(_typeContext, m, collectAnnotations(m, mixin), collectAnnotations(m.getParameterAnnotations(), (mixin == null) ? null : mixin.getParameterAnnotations())); } private AnnotationMap[] collectAnnotations(Annotation[][] mainAnns, Annotation[][] mixinAnns) { if (_collectAnnotations) { final int count = mainAnns.length; AnnotationMap[] result = new AnnotationMap[count]; for (int i = 0; i < count; ++i) { AnnotationCollector c = collectAnnotations(AnnotationCollector.emptyCollector(), mainAnns[i]); if (mixinAnns != null) { c = collectAnnotations(c, mixinAnns[i]); } result[i] = c.asAnnotationMap(); } return result; } return NO_ANNOTATION_MAPS; } // // NOTE: these are only called when we know we have AnnotationIntrospector private AnnotationMap collectAnnotations(ClassUtil.Ctor main, ClassUtil.Ctor mixin) { if (_collectAnnotations) { AnnotationCollector c = collectAnnotations(main.getDeclaredAnnotations()); if (mixin != null) { c = collectAnnotations(c, mixin.getDeclaredAnnotations()); } return c.asAnnotationMap(); } return _emptyAnnotationMap(); } private final AnnotationMap collectAnnotations(AnnotatedElement main, AnnotatedElement mixin) { AnnotationCollector c = collectAnnotations(main.getDeclaredAnnotations()); if (mixin != null) { c = collectAnnotations(c, mixin.getDeclaredAnnotations()); } return c.asAnnotationMap(); } // for [databind#1005]: do not use or expose synthetic constructors private static boolean isIncludableConstructor(Constructor<?> c) { return !c.isSynthetic(); } }