/*
* Copyright 2002-2010 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.beans.ConstructorProperties;
import java.lang.reflect.Constructor;
import java.lang.reflect.Member;
import java.lang.reflect.Method;
import java.lang.reflect.Modifier;
import java.security.AccessController;
import java.security.PrivilegedAction;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.HashSet;
import java.util.LinkedHashSet;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;
import java.util.Set;
import org.springframework.beans.BeanMetadataElement;
import org.springframework.beans.BeanWrapper;
import org.springframework.beans.BeanWrapperImpl;
import org.springframework.beans.BeansException;
import org.springframework.beans.TypeConverter;
import org.springframework.beans.TypeMismatchException;
import org.springframework.beans.factory.BeanCreationException;
import org.springframework.beans.factory.BeanDefinitionStoreException;
import org.springframework.beans.factory.UnsatisfiedDependencyException;
import org.springframework.beans.factory.config.ConstructorArgumentValues;
import org.springframework.beans.factory.config.ConstructorArgumentValues.ValueHolder;
import org.springframework.beans.factory.config.DependencyDescriptor;
import org.springframework.core.GenericTypeResolver;
import org.springframework.core.MethodParameter;
import org.springframework.core.ParameterNameDiscoverer;
import org.springframework.util.ClassUtils;
import org.springframework.util.MethodInvoker;
import org.springframework.util.ObjectUtils;
import org.springframework.util.ReflectionUtils;
import org.springframework.util.StringUtils;
/**
* Helper class for resolving constructors and factory methods.
* Performs constructor resolution through argument matching.
*
* <p>Operates on an {@link AbstractBeanFactory} and an {@link InstantiationStrategy}.
* Used by {@link AbstractAutowireCapableBeanFactory}.
*
* @author Juergen Hoeller
* @author Rob Harrop
* @author Mark Fisher
* @author Costin Leau
* @since 2.0
* @see #autowireConstructor
* @see #instantiateUsingFactoryMethod
* @see AbstractAutowireCapableBeanFactory
*/
class ConstructorResolver {
private static final String CONSTRUCTOR_PROPERTIES_CLASS_NAME = "java.beans.ConstructorProperties";
private static final boolean constructorPropertiesAnnotationAvailable =
ClassUtils.isPresent(CONSTRUCTOR_PROPERTIES_CLASS_NAME, ConstructorResolver.class.getClassLoader());
private final AbstractAutowireCapableBeanFactory beanFactory;
/**
* Create a new ConstructorResolver for the given factory and instantiation strategy.
* @param beanFactory the BeanFactory to work with
*/
public ConstructorResolver(AbstractAutowireCapableBeanFactory beanFactory) {
this.beanFactory = beanFactory;
}
/**
* "autowire constructor" (with constructor arguments by type) behavior.
* Also applied if explicit constructor argument values are specified,
* matching all remaining arguments with beans from the bean factory.
* <p>This corresponds to constructor injection: In this mode, a Spring
* bean factory is able to host components that expect constructor-based
* dependency resolution.
* @param beanName the name of the bean
* @param mbd the merged bean definition for the bean
* @param chosenCtors chosen candidate constructors (or <code>null</code> if none)
* @param explicitArgs argument values passed in programmatically via the getBean method,
* or <code>null</code> if none (-> use constructor argument values from bean definition)
* @return a BeanWrapper for the new instance
*/
public BeanWrapper autowireConstructor(
final String beanName, final RootBeanDefinition mbd, Constructor[] chosenCtors, final Object[] explicitArgs) {
BeanWrapperImpl bw = new BeanWrapperImpl();
this.beanFactory.initBeanWrapper(bw);
Constructor constructorToUse = null;
ArgumentsHolder argsHolderToUse = null;
Object[] argsToUse = null;
if (explicitArgs != null) {
argsToUse = explicitArgs;
}
else {
Object[] argsToResolve = null;
synchronized (mbd.constructorArgumentLock) {
constructorToUse = (Constructor) mbd.resolvedConstructorOrFactoryMethod;
if (constructorToUse != null && mbd.constructorArgumentsResolved) {
// Found a cached constructor...
argsToUse = mbd.resolvedConstructorArguments;
if (argsToUse == null) {
argsToResolve = mbd.preparedConstructorArguments;
}
}
}
if (argsToResolve != null) {
argsToUse = resolvePreparedArguments(beanName, mbd, bw, constructorToUse, argsToResolve);
}
}
if (constructorToUse == null) {
// Need to resolve the constructor.
boolean autowiring = (chosenCtors != null ||
mbd.getResolvedAutowireMode() == RootBeanDefinition.AUTOWIRE_CONSTRUCTOR);
ConstructorArgumentValues resolvedValues = null;
int minNrOfArgs;
if (explicitArgs != null) {
minNrOfArgs = explicitArgs.length;
}
else {
ConstructorArgumentValues cargs = mbd.getConstructorArgumentValues();
resolvedValues = new ConstructorArgumentValues();
minNrOfArgs = resolveConstructorArguments(beanName, mbd, bw, cargs, resolvedValues);
}
// Take specified constructors, if any.
Constructor[] candidates = chosenCtors;
if (candidates == null) {
Class beanClass = mbd.getBeanClass();
try {
candidates = (mbd.isNonPublicAccessAllowed() ?
beanClass.getDeclaredConstructors() : beanClass.getConstructors());
}
catch (Throwable ex) {
throw new BeanCreationException(mbd.getResourceDescription(), beanName,
"Resolution of declared constructors on bean Class [" + beanClass.getName() +
"] from ClassLoader [" + beanClass.getClassLoader() + "] failed", ex);
}
}
AutowireUtils.sortConstructors(candidates);
int minTypeDiffWeight = Integer.MAX_VALUE;
Set<Constructor> ambiguousConstructors = null;
List<Exception> causes = null;
for (int i = 0; i < candidates.length; i++) {
Constructor<?> candidate = candidates[i];
Class[] paramTypes = candidate.getParameterTypes();
if (constructorToUse != null && argsToUse.length > paramTypes.length) {
// Already found greedy constructor that can be satisfied ->
// do not look any further, there are only less greedy constructors left.
break;
}
if (paramTypes.length < minNrOfArgs) {
continue;
}
ArgumentsHolder argsHolder;
if (resolvedValues != null) {
try {
String[] paramNames = null;
if (constructorPropertiesAnnotationAvailable) {
paramNames = ConstructorPropertiesChecker.evaluateAnnotation(candidate, paramTypes.length);
}
if (paramNames == null) {
ParameterNameDiscoverer pnd = this.beanFactory.getParameterNameDiscoverer();
if (pnd != null) {
paramNames = pnd.getParameterNames(candidate);
}
}
argsHolder = createArgumentArray(
beanName, mbd, resolvedValues, bw, paramTypes, paramNames, candidate, autowiring);
}
catch (UnsatisfiedDependencyException ex) {
if (this.beanFactory.logger.isTraceEnabled()) {
this.beanFactory.logger.trace(
"Ignoring constructor [" + candidate + "] of bean '" + beanName + "': " + ex);
}
if (i == candidates.length - 1 && constructorToUse == null) {
if (causes != null) {
for (Exception cause : causes) {
this.beanFactory.onSuppressedException(cause);
}
}
throw ex;
}
else {
// Swallow and try next constructor.
if (causes == null) {
causes = new LinkedList<Exception>();
}
causes.add(ex);
continue;
}
}
}
else {
// Explicit arguments given -> arguments length must match exactly.
if (paramTypes.length != explicitArgs.length) {
continue;
}
argsHolder = new ArgumentsHolder(explicitArgs);
}
int typeDiffWeight = (mbd.isLenientConstructorResolution() ?
argsHolder.getTypeDifferenceWeight(paramTypes) : argsHolder.getAssignabilityWeight(paramTypes));
// Choose this constructor if it represents the closest match.
if (typeDiffWeight < minTypeDiffWeight) {
constructorToUse = candidate;
argsHolderToUse = argsHolder;
argsToUse = argsHolder.arguments;
minTypeDiffWeight = typeDiffWeight;
ambiguousConstructors = null;
}
else if (constructorToUse != null && typeDiffWeight == minTypeDiffWeight) {
if (ambiguousConstructors == null) {
ambiguousConstructors = new LinkedHashSet<Constructor>();
ambiguousConstructors.add(constructorToUse);
}
ambiguousConstructors.add(candidate);
}
}
if (constructorToUse == null) {
throw new BeanCreationException(mbd.getResourceDescription(), beanName,
"Could not resolve matching constructor " +
"(hint: specify index/type/name arguments for simple parameters to avoid type ambiguities)");
}
else if (ambiguousConstructors != null && !mbd.isLenientConstructorResolution()) {
throw new BeanCreationException(mbd.getResourceDescription(), beanName,
"Ambiguous constructor matches found in bean '" + beanName + "' " +
"(hint: specify index/type/name arguments for simple parameters to avoid type ambiguities): " +
ambiguousConstructors);
}
if (explicitArgs == null) {
argsHolderToUse.storeCache(mbd, constructorToUse);
}
}
try {
Object beanInstance;
if (System.getSecurityManager() != null) {
final Constructor ctorToUse = constructorToUse;
final Object[] argumentsToUse = argsToUse;
beanInstance = AccessController.doPrivileged(new PrivilegedAction<Object>() {
public Object run() {
return beanFactory.getInstantiationStrategy().instantiate(
mbd, beanName, beanFactory, ctorToUse, argumentsToUse);
}
}, beanFactory.getAccessControlContext());
}
else {
beanInstance = this.beanFactory.getInstantiationStrategy().instantiate(
mbd, beanName, this.beanFactory, constructorToUse, argsToUse);
}
bw.setWrappedInstance(beanInstance);
return bw;
}
catch (Throwable ex) {
throw new BeanCreationException(mbd.getResourceDescription(), beanName, "Instantiation of bean failed", ex);
}
}
/**
* Resolve the factory method in the specified bean definition, if possible.
* {@link RootBeanDefinition#getResolvedFactoryMethod()} can be checked for the result.
* @param mbd the bean definition to check
*/
public void resolveFactoryMethodIfPossible(RootBeanDefinition mbd) {
Class factoryClass;
if (mbd.getFactoryBeanName() != null) {
factoryClass = this.beanFactory.getType(mbd.getFactoryBeanName());
}
else {
factoryClass = mbd.getBeanClass();
}
factoryClass = ClassUtils.getUserClass(factoryClass);
Method[] candidates = ReflectionUtils.getAllDeclaredMethods(factoryClass);
Method uniqueCandidate = null;
for (Method candidate : candidates) {
if (mbd.isFactoryMethod(candidate)) {
if (uniqueCandidate == null) {
uniqueCandidate = candidate;
}
else if (!Arrays.equals(uniqueCandidate.getParameterTypes(), candidate.getParameterTypes())) {
uniqueCandidate = null;
break;
}
}
}
synchronized (mbd.constructorArgumentLock) {
mbd.resolvedConstructorOrFactoryMethod = uniqueCandidate;
}
}
/**
* Instantiate the bean using a named factory method. The method may be static, if the
* bean definition parameter specifies a class, rather than a "factory-bean", or
* an instance variable on a factory object itself configured using Dependency Injection.
* <p>Implementation requires iterating over the static or instance methods with the
* name specified in the RootBeanDefinition (the method may be overloaded) and trying
* to match with the parameters. We don't have the types attached to constructor args,
* so trial and error is the only way to go here. The explicitArgs array may contain
* argument values passed in programmatically via the corresponding getBean method.
* @param beanName the name of the bean
* @param mbd the merged bean definition for the bean
* @param explicitArgs argument values passed in programmatically via the getBean
* method, or <code>null</code> if none (-> use constructor argument values from bean definition)
* @return a BeanWrapper for the new instance
*/
public BeanWrapper instantiateUsingFactoryMethod(final String beanName, final RootBeanDefinition mbd, final Object[] explicitArgs) {
BeanWrapperImpl bw = new BeanWrapperImpl();
this.beanFactory.initBeanWrapper(bw);
Object factoryBean;
Class factoryClass;
boolean isStatic;
String factoryBeanName = mbd.getFactoryBeanName();
if (factoryBeanName != null) {
if (factoryBeanName.equals(beanName)) {
throw new BeanDefinitionStoreException(mbd.getResourceDescription(), beanName,
"factory-bean reference points back to the same bean definition");
}
factoryBean = this.beanFactory.getBean(factoryBeanName);
if (factoryBean == null) {
throw new BeanCreationException(mbd.getResourceDescription(), beanName,
"factory-bean '" + factoryBeanName + "' returned null");
}
factoryClass = factoryBean.getClass();
isStatic = false;
}
else {
// It's a static factory method on the bean class.
if (!mbd.hasBeanClass()) {
throw new BeanDefinitionStoreException(mbd.getResourceDescription(), beanName,
"bean definition declares neither a bean class nor a factory-bean reference");
}
factoryBean = null;
factoryClass = mbd.getBeanClass();
isStatic = true;
}
Method factoryMethodToUse = null;
ArgumentsHolder argsHolderToUse = null;
Object[] argsToUse = null;
if (explicitArgs != null) {
argsToUse = explicitArgs;
}
else {
Object[] argsToResolve = null;
synchronized (mbd.constructorArgumentLock) {
factoryMethodToUse = (Method) mbd.resolvedConstructorOrFactoryMethod;
if (factoryMethodToUse != null && mbd.constructorArgumentsResolved) {
// Found a cached factory method...
argsToUse = mbd.resolvedConstructorArguments;
if (argsToUse == null) {
argsToResolve = mbd.preparedConstructorArguments;
}
}
}
if (argsToResolve != null) {
argsToUse = resolvePreparedArguments(beanName, mbd, bw, factoryMethodToUse, argsToResolve);
}
}
if (factoryMethodToUse == null || argsToUse == null) {
// Need to determine the factory method...
// Try all methods with this name to see if they match the given arguments.
factoryClass = ClassUtils.getUserClass(factoryClass);
Method[] rawCandidates;
final Class factoryClazz = factoryClass;
if (System.getSecurityManager() != null) {
rawCandidates = AccessController.doPrivileged(new PrivilegedAction<Method[]>() {
public Method[] run() {
return (mbd.isNonPublicAccessAllowed() ?
ReflectionUtils.getAllDeclaredMethods(factoryClazz) : factoryClazz.getMethods());
}
});
}
else {
rawCandidates = (mbd.isNonPublicAccessAllowed() ?
ReflectionUtils.getAllDeclaredMethods(factoryClazz) : factoryClazz.getMethods());
}
List<Method> candidateSet = new ArrayList<Method>();
for (Method candidate : rawCandidates) {
if (Modifier.isStatic(candidate.getModifiers()) == isStatic &&
candidate.getName().equals(mbd.getFactoryMethodName()) &&
mbd.isFactoryMethod(candidate)) {
candidateSet.add(candidate);
}
}
Method[] candidates = candidateSet.toArray(new Method[candidateSet.size()]);
AutowireUtils.sortFactoryMethods(candidates);
ConstructorArgumentValues resolvedValues = null;
boolean autowiring = (mbd.getResolvedAutowireMode() == RootBeanDefinition.AUTOWIRE_CONSTRUCTOR);
int minTypeDiffWeight = Integer.MAX_VALUE;
Set<Method> ambiguousFactoryMethods = null;
int minNrOfArgs;
if (explicitArgs != null) {
minNrOfArgs = explicitArgs.length;
}
else {
// We don't have arguments passed in programmatically, so we need to resolve the
// arguments specified in the constructor arguments held in the bean definition.
ConstructorArgumentValues cargs = mbd.getConstructorArgumentValues();
resolvedValues = new ConstructorArgumentValues();
minNrOfArgs = resolveConstructorArguments(beanName, mbd, bw, cargs, resolvedValues);
}
List<Exception> causes = null;
for (int i = 0; i < candidates.length; i++) {
Method candidate = candidates[i];
Class[] paramTypes = candidate.getParameterTypes();
if (paramTypes.length >= minNrOfArgs) {
ArgumentsHolder argsHolder;
if (resolvedValues != null) {
// Resolved constructor arguments: type conversion and/or autowiring necessary.
try {
String[] paramNames = null;
ParameterNameDiscoverer pnd = this.beanFactory.getParameterNameDiscoverer();
if (pnd != null) {
paramNames = pnd.getParameterNames(candidate);
}
argsHolder = createArgumentArray(
beanName, mbd, resolvedValues, bw, paramTypes, paramNames, candidate, autowiring);
}
catch (UnsatisfiedDependencyException ex) {
if (this.beanFactory.logger.isTraceEnabled()) {
this.beanFactory.logger.trace("Ignoring factory method [" + candidate +
"] of bean '" + beanName + "': " + ex);
}
if (i == candidates.length - 1 && argsHolderToUse == null) {
if (causes != null) {
for (Exception cause : causes) {
this.beanFactory.onSuppressedException(cause);
}
}
throw ex;
}
else {
// Swallow and try next overloaded factory method.
if (causes == null) {
causes = new LinkedList<Exception>();
}
causes.add(ex);
continue;
}
}
}
else {
// Explicit arguments given -> arguments length must match exactly.
if (paramTypes.length != explicitArgs.length) {
continue;
}
argsHolder = new ArgumentsHolder(explicitArgs);
}
int typeDiffWeight = (mbd.isLenientConstructorResolution() ?
argsHolder.getTypeDifferenceWeight(paramTypes) : argsHolder.getAssignabilityWeight(paramTypes));
// Choose this factory method if it represents the closest match.
if (typeDiffWeight < minTypeDiffWeight) {
factoryMethodToUse = candidate;
argsHolderToUse = argsHolder;
argsToUse = argsHolder.arguments;
minTypeDiffWeight = typeDiffWeight;
ambiguousFactoryMethods = null;
}
else if (factoryMethodToUse != null && typeDiffWeight == minTypeDiffWeight) {
if (ambiguousFactoryMethods == null) {
ambiguousFactoryMethods = new LinkedHashSet<Method>();
ambiguousFactoryMethods.add(factoryMethodToUse);
}
ambiguousFactoryMethods.add(candidate);
}
}
}
if (factoryMethodToUse == null) {
boolean hasArgs = (resolvedValues.getArgumentCount() > 0);
String argDesc = "";
if (hasArgs) {
List<String> argTypes = new ArrayList<String>();
for (ValueHolder value : resolvedValues.getIndexedArgumentValues().values()) {
String argType = (value.getType() != null ?
ClassUtils.getShortName(value.getType()) : value.getValue().getClass().getSimpleName());
argTypes.add(argType);
}
argDesc = StringUtils.collectionToCommaDelimitedString(argTypes);
}
throw new BeanCreationException(mbd.getResourceDescription(), beanName,
"No matching factory method found: " +
(mbd.getFactoryBeanName() != null ?
"factory bean '" + mbd.getFactoryBeanName() + "'; " : "") +
"factory method '" + mbd.getFactoryMethodName() + "(" + argDesc + ")'. " +
"Check that a method with the specified name " +
(hasArgs ? "and arguments " : "") +
"exists and that it is " +
(isStatic ? "static" : "non-static") + ".");
}
else if (void.class.equals(factoryMethodToUse.getReturnType())) {
throw new BeanCreationException(mbd.getResourceDescription(), beanName,
"Invalid factory method '" + mbd.getFactoryMethodName() +
"': needs to have a non-void return type!");
}
else if (ambiguousFactoryMethods != null && !mbd.isLenientConstructorResolution()) {
throw new BeanCreationException(mbd.getResourceDescription(), beanName,
"Ambiguous factory method matches found in bean '" + beanName + "' " +
"(hint: specify index/type/name arguments for simple parameters to avoid type ambiguities): " +
ambiguousFactoryMethods);
}
if (explicitArgs == null && argsHolderToUse != null) {
argsHolderToUse.storeCache(mbd, factoryMethodToUse);
}
}
try {
Object beanInstance;
if (System.getSecurityManager() != null) {
final Object fb = factoryBean;
final Method factoryMethod = factoryMethodToUse;
final Object[] args = argsToUse;
beanInstance = AccessController.doPrivileged(new PrivilegedAction<Object>() {
public Object run() {
return beanFactory.getInstantiationStrategy().instantiate(
mbd, beanName, beanFactory, fb, factoryMethod, args);
}
}, beanFactory.getAccessControlContext());
}
else {
beanInstance = beanFactory.getInstantiationStrategy().instantiate(
mbd, beanName, beanFactory, factoryBean, factoryMethodToUse, argsToUse);
}
if (beanInstance == null) {
return null;
}
bw.setWrappedInstance(beanInstance);
return bw;
}
catch (Throwable ex) {
throw new BeanCreationException(mbd.getResourceDescription(), beanName, "Instantiation of bean failed", ex);
}
}
/**
* Resolve the constructor arguments for this bean into the resolvedValues object.
* This may involve looking up other beans.
* This method is also used for handling invocations of static factory methods.
*/
private int resolveConstructorArguments(
String beanName, RootBeanDefinition mbd, BeanWrapper bw,
ConstructorArgumentValues cargs, ConstructorArgumentValues resolvedValues) {
TypeConverter converter = (this.beanFactory.getCustomTypeConverter() != null ?
this.beanFactory.getCustomTypeConverter() : bw);
BeanDefinitionValueResolver valueResolver =
new BeanDefinitionValueResolver(this.beanFactory, beanName, mbd, converter);
int minNrOfArgs = cargs.getArgumentCount();
for (Map.Entry<Integer, ConstructorArgumentValues.ValueHolder> entry : cargs.getIndexedArgumentValues().entrySet()) {
int index = entry.getKey();
if (index < 0) {
throw new BeanCreationException(mbd.getResourceDescription(), beanName,
"Invalid constructor argument index: " + index);
}
if (index > minNrOfArgs) {
minNrOfArgs = index + 1;
}
ConstructorArgumentValues.ValueHolder valueHolder = entry.getValue();
if (valueHolder.isConverted()) {
resolvedValues.addIndexedArgumentValue(index, valueHolder);
}
else {
Object resolvedValue =
valueResolver.resolveValueIfNecessary("constructor argument", valueHolder.getValue());
ConstructorArgumentValues.ValueHolder resolvedValueHolder =
new ConstructorArgumentValues.ValueHolder(resolvedValue, valueHolder.getType(), valueHolder.getName());
resolvedValueHolder.setSource(valueHolder);
resolvedValues.addIndexedArgumentValue(index, resolvedValueHolder);
}
}
for (ConstructorArgumentValues.ValueHolder valueHolder : cargs.getGenericArgumentValues()) {
if (valueHolder.isConverted()) {
resolvedValues.addGenericArgumentValue(valueHolder);
}
else {
Object resolvedValue =
valueResolver.resolveValueIfNecessary("constructor argument", valueHolder.getValue());
ConstructorArgumentValues.ValueHolder resolvedValueHolder =
new ConstructorArgumentValues.ValueHolder(resolvedValue, valueHolder.getType(), valueHolder.getName());
resolvedValueHolder.setSource(valueHolder);
resolvedValues.addGenericArgumentValue(resolvedValueHolder);
}
}
return minNrOfArgs;
}
/**
* Create an array of arguments to invoke a constructor or factory method,
* given the resolved constructor argument values.
*/
private ArgumentsHolder createArgumentArray(
String beanName, RootBeanDefinition mbd, ConstructorArgumentValues resolvedValues,
BeanWrapper bw, Class[] paramTypes, String[] paramNames, Object methodOrCtor,
boolean autowiring) throws UnsatisfiedDependencyException {
String methodType = (methodOrCtor instanceof Constructor ? "constructor" : "factory method");
TypeConverter converter = (this.beanFactory.getCustomTypeConverter() != null ?
this.beanFactory.getCustomTypeConverter() : bw);
ArgumentsHolder args = new ArgumentsHolder(paramTypes.length);
Set<ConstructorArgumentValues.ValueHolder> usedValueHolders =
new HashSet<ConstructorArgumentValues.ValueHolder>(paramTypes.length);
Set<String> autowiredBeanNames = new LinkedHashSet<String>(4);
for (int paramIndex = 0; paramIndex < paramTypes.length; paramIndex++) {
Class<?> paramType = paramTypes[paramIndex];
String paramName = (paramNames != null ? paramNames[paramIndex] : null);
// Try to find matching constructor argument value, either indexed or generic.
ConstructorArgumentValues.ValueHolder valueHolder =
resolvedValues.getArgumentValue(paramIndex, paramType, paramName, usedValueHolders);
// If we couldn't find a direct match and are not supposed to autowire,
// let's try the next generic, untyped argument value as fallback:
// it could match after type conversion (for example, String -> int).
if (valueHolder == null && !autowiring) {
valueHolder = resolvedValues.getGenericArgumentValue(null, null, usedValueHolders);
}
if (valueHolder != null) {
// We found a potential match - let's give it a try.
// Do not consider the same value definition multiple times!
usedValueHolders.add(valueHolder);
Object originalValue = valueHolder.getValue();
Object convertedValue;
if (valueHolder.isConverted()) {
convertedValue = valueHolder.getConvertedValue();
args.preparedArguments[paramIndex] = convertedValue;
}
else {
ConstructorArgumentValues.ValueHolder sourceHolder =
(ConstructorArgumentValues.ValueHolder) valueHolder.getSource();
Object sourceValue = sourceHolder.getValue();
try {
convertedValue = converter.convertIfNecessary(originalValue, paramType,
MethodParameter.forMethodOrConstructor(methodOrCtor, paramIndex));
// TODO re-enable once race condition has been found (SPR-7423)
/*
if (originalValue == sourceValue || sourceValue instanceof TypedStringValue) {
// Either a converted value or still the original one: store converted value.
sourceHolder.setConvertedValue(convertedValue);
args.preparedArguments[paramIndex] = convertedValue;
}
else {
*/
args.resolveNecessary = true;
args.preparedArguments[paramIndex] = sourceValue;
// }
}
catch (TypeMismatchException ex) {
throw new UnsatisfiedDependencyException(
mbd.getResourceDescription(), beanName, paramIndex, paramType,
"Could not convert " + methodType + " argument value of type [" +
ObjectUtils.nullSafeClassName(valueHolder.getValue()) +
"] to required type [" + paramType.getName() + "]: " + ex.getMessage());
}
}
args.arguments[paramIndex] = convertedValue;
args.rawArguments[paramIndex] = originalValue;
}
else {
// No explicit match found: we're either supposed to autowire or
// have to fail creating an argument array for the given constructor.
if (!autowiring) {
throw new UnsatisfiedDependencyException(
mbd.getResourceDescription(), beanName, paramIndex, paramType,
"Ambiguous " + methodType + " argument types - " +
"did you specify the correct bean references as " + methodType + " arguments?");
}
try {
MethodParameter param = MethodParameter.forMethodOrConstructor(methodOrCtor, paramIndex);
Object autowiredArgument = resolveAutowiredArgument(param, beanName, autowiredBeanNames, converter);
args.rawArguments[paramIndex] = autowiredArgument;
args.arguments[paramIndex] = autowiredArgument;
args.preparedArguments[paramIndex] = new AutowiredArgumentMarker();
args.resolveNecessary = true;
}
catch (BeansException ex) {
throw new UnsatisfiedDependencyException(
mbd.getResourceDescription(), beanName, paramIndex, paramType, ex);
}
}
}
for (String autowiredBeanName : autowiredBeanNames) {
this.beanFactory.registerDependentBean(autowiredBeanName, beanName);
if (this.beanFactory.logger.isDebugEnabled()) {
this.beanFactory.logger.debug("Autowiring by type from bean name '" + beanName +
"' via " + methodType + " to bean named '" + autowiredBeanName + "'");
}
}
return args;
}
/**
* Resolve the prepared arguments stored in the given bean definition.
*/
private Object[] resolvePreparedArguments(
String beanName, RootBeanDefinition mbd, BeanWrapper bw, Member methodOrCtor, Object[] argsToResolve) {
Class[] paramTypes = (methodOrCtor instanceof Method ?
((Method) methodOrCtor).getParameterTypes() : ((Constructor) methodOrCtor).getParameterTypes());
TypeConverter converter = (this.beanFactory.getCustomTypeConverter() != null ?
this.beanFactory.getCustomTypeConverter() : bw);
BeanDefinitionValueResolver valueResolver =
new BeanDefinitionValueResolver(this.beanFactory, beanName, mbd, converter);
Object[] resolvedArgs = new Object[argsToResolve.length];
for (int argIndex = 0; argIndex < argsToResolve.length; argIndex++) {
Object argValue = argsToResolve[argIndex];
MethodParameter methodParam = MethodParameter.forMethodOrConstructor(methodOrCtor, argIndex);
GenericTypeResolver.resolveParameterType(methodParam, methodOrCtor.getDeclaringClass());
if (argValue instanceof AutowiredArgumentMarker) {
argValue = resolveAutowiredArgument(methodParam, beanName, null, converter);
}
else if (argValue instanceof BeanMetadataElement) {
argValue = valueResolver.resolveValueIfNecessary("constructor argument", argValue);
}
else if (argValue instanceof String) {
argValue = this.beanFactory.evaluateBeanDefinitionString((String) argValue, mbd);
}
Class<?> paramType = paramTypes[argIndex];
try {
resolvedArgs[argIndex] = converter.convertIfNecessary(argValue, paramType, methodParam);
}
catch (TypeMismatchException ex) {
String methodType = (methodOrCtor instanceof Constructor ? "constructor" : "factory method");
throw new UnsatisfiedDependencyException(
mbd.getResourceDescription(), beanName, argIndex, paramType,
"Could not convert " + methodType + " argument value of type [" +
ObjectUtils.nullSafeClassName(argValue) +
"] to required type [" + paramType.getName() + "]: " + ex.getMessage());
}
}
return resolvedArgs;
}
/**
* Template method for resolving the specified argument which is supposed to be autowired.
*/
protected Object resolveAutowiredArgument(
MethodParameter param, String beanName, Set<String> autowiredBeanNames, TypeConverter typeConverter) {
return this.beanFactory.resolveDependency(
new DependencyDescriptor(param, true), beanName, autowiredBeanNames, typeConverter);
}
/**
* Private inner class for holding argument combinations.
*/
private static class ArgumentsHolder {
public final Object rawArguments[];
public final Object arguments[];
public final Object preparedArguments[];
public boolean resolveNecessary = false;
public ArgumentsHolder(int size) {
this.rawArguments = new Object[size];
this.arguments = new Object[size];
this.preparedArguments = new Object[size];
}
public ArgumentsHolder(Object[] args) {
this.rawArguments = args;
this.arguments = args;
this.preparedArguments = args;
}
public int getTypeDifferenceWeight(Class[] paramTypes) {
// If valid arguments found, determine type difference weight.
// Try type difference weight on both the converted arguments and
// the raw arguments. If the raw weight is better, use it.
// Decrease raw weight by 1024 to prefer it over equal converted weight.
int typeDiffWeight = MethodInvoker.getTypeDifferenceWeight(paramTypes, this.arguments);
int rawTypeDiffWeight = MethodInvoker.getTypeDifferenceWeight(paramTypes, this.rawArguments) - 1024;
return (rawTypeDiffWeight < typeDiffWeight ? rawTypeDiffWeight : typeDiffWeight);
}
public int getAssignabilityWeight(Class[] paramTypes) {
for (int i = 0; i < paramTypes.length; i++) {
if (!ClassUtils.isAssignableValue(paramTypes[i], this.arguments[i])) {
return Integer.MAX_VALUE;
}
}
for (int i = 0; i < paramTypes.length; i++) {
if (!ClassUtils.isAssignableValue(paramTypes[i], this.rawArguments[i])) {
return Integer.MAX_VALUE - 512;
}
}
return Integer.MAX_VALUE - 1024;
}
public void storeCache(RootBeanDefinition mbd, Object constructorOrFactoryMethod) {
synchronized (mbd.constructorArgumentLock) {
mbd.resolvedConstructorOrFactoryMethod = constructorOrFactoryMethod;
mbd.constructorArgumentsResolved = true;
if (this.resolveNecessary) {
mbd.preparedConstructorArguments = this.preparedArguments;
}
else {
mbd.resolvedConstructorArguments = this.arguments;
}
}
}
}
/**
* Marker for autowired arguments in a cached argument array.
*/
private static class AutowiredArgumentMarker {
}
/**
* Inner class to avoid a Java 6 dependency.
*/
private static class ConstructorPropertiesChecker {
public static String[] evaluateAnnotation(Constructor<?> candidate, int paramCount) {
ConstructorProperties cp = candidate.getAnnotation(ConstructorProperties.class);
if (cp != null) {
String[] names = cp.value();
if (names.length != paramCount) {
throw new IllegalStateException("Constructor annotated with @ConstructorProperties but not " +
"corresponding to actual number of parameters (" + paramCount + "): " + candidate);
}
return names;
}
else {
return null;
}
}
}
}
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