/*
* Copyright 2002-2018 the original author or authors.
*
* Licensed 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
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.springframework.beans.factory.support;
import java.lang.reflect.AnnotatedElement;
import java.lang.reflect.Constructor;
import java.lang.reflect.Executable;
import java.lang.reflect.Member;
import java.lang.reflect.Method;
import java.util.HashSet;
import java.util.Set;
import java.util.function.Supplier;
import org.springframework.beans.MutablePropertyValues;
import org.springframework.beans.factory.config.BeanDefinition;
import org.springframework.beans.factory.config.BeanDefinitionHolder;
import org.springframework.beans.factory.config.ConstructorArgumentValues;
import org.springframework.core.ResolvableType;
import org.springframework.lang.Nullable;
import org.springframework.util.Assert;
/**
* A root bean definition represents the merged bean definition that backs
* a specific bean in a Spring BeanFactory at runtime. It might have been created
* from multiple original bean definitions that inherit from each other,
* typically registered as {@link GenericBeanDefinition GenericBeanDefinitions}.
* A root bean definition is essentially the 'unified' bean definition view at runtime.
*
* <p>Root bean definitions may also be used for registering individual bean definitions
* in the configuration phase. However, since Spring 2.5, the preferred way to register
* bean definitions programmatically is the {@link GenericBeanDefinition} class.
* GenericBeanDefinition has the advantage that it allows to dynamically define
* parent dependencies, not 'hard-coding' the role as a root bean definition.
*
* @author Rod Johnson
* @author Juergen Hoeller
* @see GenericBeanDefinition
* @see ChildBeanDefinition
*/
@SuppressWarnings("serial")
public class RootBeanDefinition extends AbstractBeanDefinition {
@Nullable
private BeanDefinitionHolder decoratedDefinition;
@Nullable
private AnnotatedElement qualifiedElement;
boolean allowCaching = true;
boolean isFactoryMethodUnique = false;
@Nullable
volatile ResolvableType targetType;
/** Package-visible field for caching the determined Class of a given bean definition. */
@Nullable
volatile Class<?> resolvedTargetType;
/** Package-visible field for caching the return type of a generically typed factory method. */
@Nullable
volatile ResolvableType factoryMethodReturnType;
/** Package-visible field for caching a unique factory method candidate for introspection. */
@Nullable
volatile Method factoryMethodToIntrospect;
/** Common lock for the four constructor fields below. */
final Object constructorArgumentLock = new Object();
/** Package-visible field for caching the resolved constructor or factory method. */
@Nullable
Executable resolvedConstructorOrFactoryMethod;
/** Package-visible field that marks the constructor arguments as resolved. */
boolean constructorArgumentsResolved = false;
/** Package-visible field for caching fully resolved constructor arguments. */
@Nullable
Object[] resolvedConstructorArguments;
/** Package-visible field for caching partly prepared constructor arguments. */
@Nullable
Object[] preparedConstructorArguments;
/** Common lock for the two post-processing fields below. */
final Object postProcessingLock = new Object();
/** Package-visible field that indicates MergedBeanDefinitionPostProcessor having been applied. */
boolean postProcessed = false;
/** Package-visible field that indicates a before-instantiation post-processor having kicked in. */
@Nullable
volatile Boolean beforeInstantiationResolved;
@Nullable
private Set<Member> externallyManagedConfigMembers;
@Nullable
private Set<String> externallyManagedInitMethods;
@Nullable
private Set<String> externallyManagedDestroyMethods;
/**
* Create a new RootBeanDefinition, to be configured through its bean
* properties and configuration methods.
* @see #setBeanClass
* @see #setScope
* @see #setConstructorArgumentValues
* @see #setPropertyValues
*/
public RootBeanDefinition() {
super();
}
/**
* Create a new RootBeanDefinition for a singleton.
* @param beanClass the class of the bean to instantiate
* @see #setBeanClass
*/
public RootBeanDefinition(@Nullable Class<?> beanClass) {
super();
setBeanClass(beanClass);
}
/**
* Create a new RootBeanDefinition for a singleton bean, constructing each instance
* through calling the given supplier (possibly a lambda or method reference).
* @param beanClass the class of the bean to instantiate
* @param instanceSupplier the supplier to construct a bean instance,
* as an alternative to a declaratively specified factory method
* @since 5.0
* @see #setInstanceSupplier
*/
public <T> RootBeanDefinition(@Nullable Class<T> beanClass, @Nullable Supplier<T> instanceSupplier) {
super();
setBeanClass(beanClass);
setInstanceSupplier(instanceSupplier);
}
/**
* Create a new RootBeanDefinition for a scoped bean, constructing each instance
* through calling the given supplier (possibly a lambda or method reference).
* @param beanClass the class of the bean to instantiate
* @param scope the name of the corresponding scope
* @param instanceSupplier the supplier to construct a bean instance,
* as an alternative to a declaratively specified factory method
* @since 5.0
* @see #setInstanceSupplier
*/
public <T> RootBeanDefinition(@Nullable Class<T> beanClass, String scope, @Nullable Supplier<T> instanceSupplier) {
super();
setBeanClass(beanClass);
setScope(scope);
setInstanceSupplier(instanceSupplier);
}
/**
* Create a new RootBeanDefinition for a singleton,
* using the given autowire mode.
* @param beanClass the class of the bean to instantiate
* @param autowireMode by name or type, using the constants in this interface
* @param dependencyCheck whether to perform a dependency check for objects
* (not applicable to autowiring a constructor, thus ignored there)
*/
public RootBeanDefinition(@Nullable Class<?> beanClass, int autowireMode, boolean dependencyCheck) {
super();
setBeanClass(beanClass);
setAutowireMode(autowireMode);
if (dependencyCheck && getResolvedAutowireMode() != AUTOWIRE_CONSTRUCTOR) {
setDependencyCheck(DEPENDENCY_CHECK_OBJECTS);
}
}
/**
* Create a new RootBeanDefinition for a singleton,
* providing constructor arguments and property values.
* @param beanClass the class of the bean to instantiate
* @param cargs the constructor argument values to apply
* @param pvs the property values to apply
*/
public RootBeanDefinition(@Nullable Class<?> beanClass, @Nullable ConstructorArgumentValues cargs,
@Nullable MutablePropertyValues pvs) {
super(cargs, pvs);
setBeanClass(beanClass);
}
/**
* Create a new RootBeanDefinition for a singleton,
* providing constructor arguments and property values.
* <p>Takes a bean class name to avoid eager loading of the bean class.
* @param beanClassName the name of the class to instantiate
*/
public RootBeanDefinition(String beanClassName) {
setBeanClassName(beanClassName);
}
/**
* Create a new RootBeanDefinition for a singleton,
* providing constructor arguments and property values.
* <p>Takes a bean class name to avoid eager loading of the bean class.
* @param beanClassName the name of the class to instantiate
* @param cargs the constructor argument values to apply
* @param pvs the property values to apply
*/
public RootBeanDefinition(String beanClassName, ConstructorArgumentValues cargs, MutablePropertyValues pvs) {
super(cargs, pvs);
setBeanClassName(beanClassName);
}
/**
* Create a new RootBeanDefinition as deep copy of the given
* bean definition.
* @param original the original bean definition to copy from
*/
public RootBeanDefinition(RootBeanDefinition original) {
super(original);
this.decoratedDefinition = original.decoratedDefinition;
this.qualifiedElement = original.qualifiedElement;
this.allowCaching = original.allowCaching;
this.isFactoryMethodUnique = original.isFactoryMethodUnique;
this.targetType = original.targetType;
}
/**
* Create a new RootBeanDefinition as deep copy of the given
* bean definition.
* @param original the original bean definition to copy from
*/
RootBeanDefinition(BeanDefinition original) {
super(original);
}
@Override
public String getParentName() {
return null;
}
@Override
public void setParentName(@Nullable String parentName) {
if (parentName != null) {
throw new IllegalArgumentException("Root bean cannot be changed into a child bean with parent reference");
}
}
/**
* Register a target definition that is being decorated by this bean definition.
*/
public void setDecoratedDefinition(@Nullable BeanDefinitionHolder decoratedDefinition) {
this.decoratedDefinition = decoratedDefinition;
}
/**
* Return the target definition that is being decorated by this bean definition, if any.
*/
@Nullable
public BeanDefinitionHolder getDecoratedDefinition() {
return this.decoratedDefinition;
}
/**
* Specify the {@link AnnotatedElement} defining qualifiers,
* to be used instead of the target class or factory method.
* @since 4.3.3
* @see #setTargetType(ResolvableType)
* @see #getResolvedFactoryMethod()
*/
public void setQualifiedElement(@Nullable AnnotatedElement qualifiedElement) {
this.qualifiedElement = qualifiedElement;
}
/**
* Return the {@link AnnotatedElement} defining qualifiers, if any.
* Otherwise, the factory method and target class will be checked.
* @since 4.3.3
*/
@Nullable
public AnnotatedElement getQualifiedElement() {
return this.qualifiedElement;
}
/**
* Specify a generics-containing target type of this bean definition, if known in advance.
* @since 4.3.3
*/
public void setTargetType(ResolvableType targetType) {
this.targetType = targetType;
}
/**
* Specify the target type of this bean definition, if known in advance.
* @since 3.2.2
*/
public void setTargetType(@Nullable Class<?> targetType) {
this.targetType = (targetType != null ? ResolvableType.forClass(targetType) : null);
}
/**
* Return the target type of this bean definition, if known
* (either specified in advance or resolved on first instantiation).
* @since 3.2.2
*/
@Nullable
public Class<?> getTargetType() {
if (this.resolvedTargetType != null) {
return this.resolvedTargetType;
}
ResolvableType targetType = this.targetType;
return (targetType != null ? targetType.resolve() : null);
}
/**
* Return a {@link ResolvableType} for this bean definition,
* either from runtime-cached type information or from configuration-time
* {@link #setTargetType(ResolvableType)} or {@link #setBeanClass(Class)}.
* @since 5.1
* @see #getTargetType()
* @see #getBeanClass()
*/
public ResolvableType getResolvableType() {
ResolvableType targetType = this.targetType;
return (targetType != null ? targetType : ResolvableType.forClass(getBeanClass()));
}
/**
* Determine preferred constructors to use for default construction, if any.
* Constructor arguments will be autowired if necessary.
* @return one or more preferred constructors, or {@code null} if none
* (in which case the regular no-arg default constructor will be called)
* @since 5.1
*/
@Nullable
public Constructor<?>[] getPreferredConstructors() {
return null;
}
/**
* Specify a factory method name that refers to a non-overloaded method.
*/
public void setUniqueFactoryMethodName(String name) {
Assert.hasText(name, "Factory method name must not be empty");
setFactoryMethodName(name);
this.isFactoryMethodUnique = true;
}
/**
* Check whether the given candidate qualifies as a factory method.
*/
public boolean isFactoryMethod(Method candidate) {
return candidate.getName().equals(getFactoryMethodName());
}
/**
* Return the resolved factory method as a Java Method object, if available.
* @return the factory method, or {@code null} if not found or not resolved yet
*/
@Nullable
public Method getResolvedFactoryMethod() {
return this.factoryMethodToIntrospect;
}
public void registerExternallyManagedConfigMember(Member configMember) {
synchronized (this.postProcessingLock) {
if (this.externallyManagedConfigMembers == null) {
this.externallyManagedConfigMembers = new HashSet<>(1);
}
this.externallyManagedConfigMembers.add(configMember);
}
}
public boolean isExternallyManagedConfigMember(Member configMember) {
synchronized (this.postProcessingLock) {
return (this.externallyManagedConfigMembers != null &&
this.externallyManagedConfigMembers.contains(configMember));
}
}
public void registerExternallyManagedInitMethod(String initMethod) {
synchronized (this.postProcessingLock) {
if (this.externallyManagedInitMethods == null) {
this.externallyManagedInitMethods = new HashSet<>(1);
}
this.externallyManagedInitMethods.add(initMethod);
}
}
public boolean isExternallyManagedInitMethod(String initMethod) {
synchronized (this.postProcessingLock) {
return (this.externallyManagedInitMethods != null &&
this.externallyManagedInitMethods.contains(initMethod));
}
}
public void registerExternallyManagedDestroyMethod(String destroyMethod) {
synchronized (this.postProcessingLock) {
if (this.externallyManagedDestroyMethods == null) {
this.externallyManagedDestroyMethods = new HashSet<>(1);
}
this.externallyManagedDestroyMethods.add(destroyMethod);
}
}
public boolean isExternallyManagedDestroyMethod(String destroyMethod) {
synchronized (this.postProcessingLock) {
return (this.externallyManagedDestroyMethods != null &&
this.externallyManagedDestroyMethods.contains(destroyMethod));
}
}
@Override
public RootBeanDefinition cloneBeanDefinition() {
return new RootBeanDefinition(this);
}
@Override
public boolean equals(Object other) {
return (this == other || (other instanceof RootBeanDefinition && super.equals(other)));
}
@Override
public String toString() {
return "Root bean: " + super.toString();
}
}
