package com.alibaba.spring.util;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.beans.factory.annotation.AnnotatedBeanDefinition;
import org.springframework.beans.factory.config.BeanDefinition;
import org.springframework.beans.factory.config.BeanDefinitionHolder;
import org.springframework.beans.factory.config.SingletonBeanRegistry;
import org.springframework.beans.factory.support.BeanDefinitionRegistry;
import org.springframework.beans.factory.support.BeanNameGenerator;
import org.springframework.context.annotation.AnnotatedBeanDefinitionReader;
import org.springframework.context.annotation.AnnotationBeanNameGenerator;
import org.springframework.context.annotation.AnnotationConfigUtils;
import org.springframework.context.annotation.ClassPathBeanDefinitionScanner;
import org.springframework.context.annotation.ConfigurationClassPostProcessor;
import org.springframework.core.type.AnnotationMetadata;
import org.springframework.stereotype.Component;
import org.springframework.util.ObjectUtils;
import java.lang.annotation.Annotation;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Iterator;
import java.util.LinkedHashSet;
import java.util.List;
import java.util.Set;
import static com.alibaba.spring.util.ClassUtils.EMPTY_CLASS_ARRAY;
import static java.lang.String.format;
import static java.util.Arrays.asList;
import static org.springframework.context.annotation.AnnotationConfigUtils.CONFIGURATION_BEAN_NAME_GENERATOR;
import static org.springframework.util.ClassUtils.resolveClassName;
import static org.springframework.util.ObjectUtils.nullSafeEquals;
/**
* Annotated {@link BeanDefinition} Utilities
*
* @author <a href="mailto:[email protected]">Mercy</a>
* @see BeanDefinition
* @since 2017.01.09
*/
public abstract class AnnotatedBeanDefinitionRegistryUtils {
private static final Log logger = LogFactory.getLog(AnnotatedBeanDefinitionRegistryUtils.class);
/**
* Is present bean that was registered by the specified {@link Annotation annotated} {@link Class class}
*
* @param registry {@link BeanDefinitionRegistry}
* @param annotatedClass the {@link Annotation annotated} {@link Class class}
* @return if present, return <code>true</code>, or <code>false</code>
* @since 1.0.3
*/
public static boolean isPresentBean(BeanDefinitionRegistry registry, Class<?> annotatedClass) {
boolean present = false;
String[] beanNames = registry.getBeanDefinitionNames();
ClassLoader classLoader = annotatedClass.getClassLoader();
for (String beanName : beanNames) {
BeanDefinition beanDefinition = registry.getBeanDefinition(beanName);
if (beanDefinition instanceof AnnotatedBeanDefinition) {
AnnotationMetadata annotationMetadata = ((AnnotatedBeanDefinition) beanDefinition).getMetadata();
String className = annotationMetadata.getClassName();
Class<?> targetClass = resolveClassName(className, classLoader);
present = nullSafeEquals(targetClass, annotatedClass);
if (present) {
if (logger.isDebugEnabled()) {
logger.debug(format("The annotatedClass[class : %s , bean name : %s] was present in registry[%s]",
className, beanName, registry));
}
break;
}
}
}
return present;
}
/**
* Register Beans if not present in {@link BeanDefinitionRegistry registry}
*
* @param registry {@link BeanDefinitionRegistry}
* @param annotatedClasses {@link Annotation annotation} class
*/
public static void registerBeans(BeanDefinitionRegistry registry, Class<?>... annotatedClasses) {
if (ObjectUtils.isEmpty(annotatedClasses)) {
return;
}
Set<Class<?>> classesToRegister = new LinkedHashSet<Class<?>>(asList(annotatedClasses));
// Remove all annotated-classes that have been registered
Iterator<Class<?>> iterator = classesToRegister.iterator();
while (iterator.hasNext()) {
Class<?> annotatedClass = iterator.next();
if (isPresentBean(registry, annotatedClass)) {
iterator.remove();
}
}
AnnotatedBeanDefinitionReader reader = new AnnotatedBeanDefinitionReader(registry);
if (logger.isDebugEnabled()) {
logger.debug(registry.getClass().getSimpleName() + " will register annotated classes : " + asList(annotatedClasses) + " .");
}
reader.register(classesToRegister.toArray(EMPTY_CLASS_ARRAY));
}
/**
* Scan base packages for register {@link Component @Component}s
*
* @param registry {@link BeanDefinitionRegistry}
* @param basePackages base packages
* @return the count of registered components.
*/
public static int scanBasePackages(BeanDefinitionRegistry registry, String... basePackages) {
int count = 0;
if (!ObjectUtils.isEmpty(basePackages)) {
boolean debugEnabled = logger.isDebugEnabled();
if (debugEnabled) {
logger.debug(registry.getClass().getSimpleName() + " will scan base packages " + Arrays.asList(basePackages) + ".");
}
List<String> registeredBeanNames = Arrays.asList(registry.getBeanDefinitionNames());
ClassPathBeanDefinitionScanner classPathBeanDefinitionScanner = new ClassPathBeanDefinitionScanner(registry);
count = classPathBeanDefinitionScanner.scan(basePackages);
List<String> scannedBeanNames = new ArrayList<String>(count);
scannedBeanNames.addAll(Arrays.asList(registry.getBeanDefinitionNames()));
scannedBeanNames.removeAll(registeredBeanNames);
if (debugEnabled) {
logger.debug("The Scanned Components[ count : " + count + "] under base packages " + Arrays.asList(basePackages) + " : ");
}
for (String scannedBeanName : scannedBeanNames) {
BeanDefinition scannedBeanDefinition = registry.getBeanDefinition(scannedBeanName);
if (debugEnabled) {
logger.debug("Component [ name : " + scannedBeanName + " , class : " + scannedBeanDefinition.getBeanClassName() + " ]");
}
}
}
return count;
}
/**
* It'd better to use BeanNameGenerator instance that should reference
* {@link ConfigurationClassPostProcessor#componentScanBeanNameGenerator},
* thus it maybe a potential problem on bean name generation.
*
* @param registry {@link BeanDefinitionRegistry}
* @return try to find the {@link BeanNameGenerator} bean named {@link AnnotationConfigUtils#CONFIGURATION_BEAN_NAME_GENERATOR},
* if it can't be found, return an instance of {@link AnnotationBeanNameGenerator}
* @see SingletonBeanRegistry
* @see AnnotationConfigUtils#CONFIGURATION_BEAN_NAME_GENERATOR
* @see ConfigurationClassPostProcessor#processConfigBeanDefinitions
* @since 1.0.6
*/
public static BeanNameGenerator resolveAnnotatedBeanNameGenerator(BeanDefinitionRegistry registry) {
BeanNameGenerator beanNameGenerator = null;
if (registry instanceof SingletonBeanRegistry) {
SingletonBeanRegistry singletonBeanRegistry = SingletonBeanRegistry.class.cast(registry);
beanNameGenerator = (BeanNameGenerator) singletonBeanRegistry.getSingleton(CONFIGURATION_BEAN_NAME_GENERATOR);
}
if (beanNameGenerator == null) {
if (logger.isInfoEnabled()) {
logger.info("BeanNameGenerator bean can't be found in BeanFactory with name ["
+ CONFIGURATION_BEAN_NAME_GENERATOR + "]");
logger.info("BeanNameGenerator will be a instance of " +
AnnotationBeanNameGenerator.class.getName() +
" , it maybe a potential problem on bean name generation.");
}
beanNameGenerator = new AnnotationBeanNameGenerator();
}
return beanNameGenerator;
}
/**
* Finds a {@link Set} of {@link BeanDefinitionHolder BeanDefinitionHolders}
*
* @param scanner {@link ClassPathBeanDefinitionScanner}
* @param packageToScan package to scan
* @param registry {@link BeanDefinitionRegistry}
* @param beanNameGenerator {@link BeanNameGenerator}
* @return non-null
*/
public static Set<BeanDefinitionHolder> findBeanDefinitionHolders(ClassPathBeanDefinitionScanner scanner,
String packageToScan,
BeanDefinitionRegistry registry,
BeanNameGenerator beanNameGenerator) {
Set<BeanDefinition> beanDefinitions = scanner.findCandidateComponents(packageToScan);
Set<BeanDefinitionHolder> beanDefinitionHolders = new LinkedHashSet<BeanDefinitionHolder>(beanDefinitions.size());
for (BeanDefinition beanDefinition : beanDefinitions) {
String beanName = beanNameGenerator.generateBeanName(beanDefinition, registry);
BeanDefinitionHolder beanDefinitionHolder = new BeanDefinitionHolder(beanDefinition, beanName);
beanDefinitionHolders.add(beanDefinitionHolder);
}
return beanDefinitionHolders;
}
}
