spring注解有哪些_Spring 注解

public class AppConfig1 { @Bean public Man getMan() { Man man = new Man(); man.setName("吕彬彬"); man.setAge(23); return man; } @Bean public Man getMan2() { return getMan(); } public static void main(String[] args) { AnnotationConfigApplicationContext ac = new AnnotationConfigApplicationContext(AppConfig1.class); 
　　　　//传入的AppConfig1就是配置类，可以不标注@Configuration也能使用 String[] names = ac.getBeanDefinitionNames(); for (String string : names) { System.out.println(string+"==="+ac.getBean(string)); } ac.close(); }

　　　　　AnnotationConfigApplicationContext ac = new AnnotationConfigApplicationContext(); ac.register(AppConfig1.class); ac.refresh(); String[] names = ac.getBeanDefinitionNames(); for (String string : names) { System.out.println(string+"==="+ac.getBean(string)); } ac.close();

 1 public void postProcessBeanDefinitionRegistry(BeanDefinitionRegistry registry) { //registry就是传入的Spring的基本容器BeanFactory对象，最常见的是DefaultListableBeanFactory  2         int registryId = System.identityHashCode(registry);  3         if (this.registriesPostProcessed.contains(registryId)) {  4             throw new IllegalStateException(  5                     "postProcessBeanDefinitionRegistry already called on this post-processor against " + registry);  6  }  7         if (this.factoriesPostProcessed.contains(registryId)) {  8             throw new IllegalStateException(  9                     "postProcessBeanFactory already called on this post-processor against " + registry); 10  } 11         this.registriesPostProcessed.add(registryId); 12 
13  processConfigBeanDefinitions(registry);　　　　　　　　　　　　　
　　　　　　 //Spring给的解释该方法是Build and validate a configuration model based on the registry of Configuration classes. 14     }

 1     public void processConfigBeanDefinitions(BeanDefinitionRegistry registry) {  2         List<BeanDefinitionHolder> configCandidates = new ArrayList<>();  3         String[] candidateNames = registry.getBeanDefinitionNames();    //遍历现有注册的所有bean, 包括了之前的配置类AppConfig1，类型是AnnotatedGenericBeanDefinition
 4 
 5         for (String beanName : candidateNames) {  6             BeanDefinition beanDef = registry.getBeanDefinition(beanName);  7             if (ConfigurationClassUtils.isFullConfigurationClass(beanDef) ||
 8                     ConfigurationClassUtils.isLiteConfigurationClass(beanDef)) { 
　　　　　　//判断beanDef有没有CONFIGURATION_CLASS_FULL属性(代表有Configuration注解) CONFIGURATION_CLASS_LITE属性代表有@Bean注解
　　　　　　//只有解析过的beanDef才会有这两种属性 
 9                 if (logger.isDebugEnabled()) {  10                     logger.debug("Bean definition has already been processed as a configuration class: " + beanDef);  11  }  12  }  13             else if (ConfigurationClassUtils.checkConfigurationClassCandidate(beanDef, this.metadataReaderFactory)) {  
　　　　　　　　　　　　//checkConfigurationClassCandidate方法做了以下操作:
　　　　　　　　　　　　// 有@Configuration注解我就给beanDef添加属性CONFIGURATION_CLASS_FULL
　　　　　　　　　　　　// 有@Bean注解我就给beanDef添加属性CONFIGURATION_CLASS_LITE
　　　　　　　　　　　　// 如果两种注解都没有直接返回false,相反有一种都能为true, 就会添加到config候选集合中
 14                 configCandidates.add(new BeanDefinitionHolder(beanDef, beanName));                                         
 15  }  16  }  17         
 18         // config候选集合为空直接返回
 19         if (configCandidates.isEmpty()) {  20             return;  21  } 46 　　　　　....省略代码

 47         // Configuration类解析器
 48         ConfigurationClassParser parser = new ConfigurationClassParser(  49                 this.metadataReaderFactory, this.problemReporter, this.environment,  50                 this.resourceLoader, this.componentScanBeanNameGenerator, registry);  51 
 52         Set<BeanDefinitionHolder> candidates = new LinkedHashSet<>(configCandidates); // config候选集合candidates  53         Set<ConfigurationClass> alreadyParsed = new HashSet<>(configCandidates.size());  54         do {  55             parser.parse(candidates);        
　　// 开始解析Configuration类，解析过程较为复杂， 简单的针对@Bean对象， parser的configurationClasses集合中添加的ConfigurationClass中持有BeanMethod对象，就是含有@Bean标签的方法
 56             parser.validate();               //验证config配置类不能为final类型，还有@Bean方法如果是static的也无需验证
 57 
 58             Set<ConfigurationClass> configClasses = new LinkedHashSet<>(parser.getConfigurationClasses());  59  configClasses.removeAll(alreadyParsed);  60 
 62             if (this.reader == null) {  63                 this.reader = new ConfigurationClassBeanDefinitionReader(  64                         registry, this.sourceExtractor, this.resourceLoader, this.environment,  65                         this.importBeanNameGenerator, parser.getImportRegistry());　　　　  66  }  67             this.reader.loadBeanDefinitions(configClasses); 
　　　　　　//读取ConfigurationClass的集合，根据BeanMethod来创建ConfigurationClassBeanDefinition，也是一种BeanDefinition对象，不同之处是创建的使用的是factory-method工厂方式创建的
　　　　　　//每个ConfigurationClassBeanDefinition的工厂名就是配置类的ID，工厂方法就是@Bean得方法名；
　　　　　　//同样还有很多处理，比如@Bean的属性设置、init-Method、destroy-Method ; Lazy 、DependsOn等注解的解析 , 还有很多额外的注解的解析就不介绍了；最后解析完成会注册到registry中  68  alreadyParsed.addAll(configClasses);  69 
 70  candidates.clear();  71             if (registry.getBeanDefinitionCount() > candidateNames.length) {  72                 String[] newCandidateNames = registry.getBeanDefinitionNames();  73                 Set<String> oldCandidateNames = new HashSet<>(Arrays.asList(candidateNames));  74                 Set<String> alreadyParsedClasses = new HashSet<>();  75                 for (ConfigurationClass configurationClass : alreadyParsed) {  76  alreadyParsedClasses.add(configurationClass.getMetadata().getClassName());  77  }  78                 for (String candidateName : newCandidateNames) {  79                     if (!oldCandidateNames.contains(candidateName)) {  80                         BeanDefinition bd = registry.getBeanDefinition(candidateName);  81                         if (ConfigurationClassUtils.checkConfigurationClassCandidate(bd, this.metadataReaderFactory) &&
 82                                 !alreadyParsedClasses.contains(bd.getBeanClassName())) {  83                             candidates.add(new BeanDefinitionHolder(bd, candidateName));  84  }  85  }  86  }  87                 candidateNames = newCandidateNames;  88  }  89  }  90         while (!candidates.isEmpty());  
 93         if (sbr != null && !sbr.containsSingleton(IMPORT_REGISTRY_BEAN_NAME)) {  94  sbr.registerSingleton(IMPORT_REGISTRY_BEAN_NAME, parser.getImportRegistry());  95  }
 97         if (this.metadataReaderFactory instanceof CachingMetadataReaderFactory) {      
100             ((CachingMetadataReaderFactory) this.metadataReaderFactory).clearCache(); 101  } 102     }

public void postProcessBeanFactory(ConfigurableListableBeanFactory beanFactory) { int factoryId = System.identityHashCode(beanFactory); if (this.factoriesPostProcessed.contains(factoryId)) { throw new IllegalStateException( "postProcessBeanFactory already called on this post-processor against " + beanFactory); } this.factoriesPostProcessed.add(factoryId); if (!this.registriesPostProcessed.contains(factoryId)) { // BeanDefinitionRegistryPostProcessor hook apparently not supported... // Simply call processConfigurationClasses lazily at this point then.
 processConfigBeanDefinitions((BeanDefinitionRegistry) beanFactory); } enhanceConfigurationClasses(beanFactory); beanFactory.addBeanPostProcessor(new ImportAwareBeanPostProcessor(beanFactory)); }

    public Object instantiate(RootBeanDefinition bd, @Nullable String beanName, BeanFactory owner, @Nullable Object factoryBean, final Method factoryMethod, Object... args) { try { if (System.getSecurityManager() != null) { AccessController.doPrivileged((PrivilegedAction<Object>) () -> { ReflectionUtils.makeAccessible(factoryMethod); return null; }); } else { ReflectionUtils.makeAccessible(factoryMethod); } Method priorInvokedFactoryMethod = currentlyInvokedFactoryMethod.get(); //currentlyInvokedFactoryMethod为ThreadLocal对象，实例化Bean的时候会记录当前的factoryMethod try { currentlyInvokedFactoryMethod.set(factoryMethod); Object result = factoryMethod.invoke(factoryBean, args);　　　　　　　　//调用反射实例化该@Bean对象 if (result == null) { result = new NullBean(); } return result; } finally {　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　//实例化完成后恢复currentlyInvokedFactoryMethod为之前的值 if (priorInvokedFactoryMethod != null) { currentlyInvokedFactoryMethod.set(priorInvokedFactoryMethod); } else { currentlyInvokedFactoryMethod.remove();　　　　　　　　 } } } catch (IllegalArgumentException ex) { throw new BeanInstantiationException(factoryMethod, "Illegal arguments to factory method '" + factoryMethod.getName() + "'; " +
                    "args: " + StringUtils.arrayToCommaDelimitedString(args), ex); } catch (IllegalAccessException ex) { throw new BeanInstantiationException(factoryMethod, "Cannot access factory method '" + factoryMethod.getName() + "'; is it public?", ex); } catch (InvocationTargetException ex) { String msg = "Factory method '" + factoryMethod.getName() + "' threw exception"; if (bd.getFactoryBeanName() != null && owner instanceof ConfigurableBeanFactory && ((ConfigurableBeanFactory) owner).isCurrentlyInCreation(bd.getFactoryBeanName())) { msg = "Circular reference involving containing bean '" + bd.getFactoryBeanName() + "' - consider " +
                        "declaring the factory method as static for independence from its containing instance. " + msg; } throw new BeanInstantiationException(factoryMethod, msg, ex.getTargetException()); } }

public void enhanceConfigurationClasses(ConfigurableListableBeanFactory beanFactory) { Map<String, AbstractBeanDefinition> configBeanDefs = new LinkedHashMap<>(); for (String beanName : beanFactory.getBeanDefinitionNames()) { BeanDefinition beanDef = beanFactory.getBeanDefinition(beanName); if (ConfigurationClassUtils.isFullConfigurationClass(beanDef)) {
　　　　//遍历了所有的BeanDefinition对象，没有CONFIGURATION_CLASS_FULL就是空的configBeanDefs，方法之前直接返回了； if (!(beanDef instanceof AbstractBeanDefinition)) { throw new BeanDefinitionStoreException("Cannot enhance @Configuration bean definition '" + beanName + "' since it is not stored in an AbstractBeanDefinition subclass"); } else if (logger.isInfoEnabled() && beanFactory.containsSingleton(beanName)) { logger.info("Cannot enhance @Configuration bean definition '" + beanName +
                            "' since its singleton instance has been created too early. The typical cause " +
                            "is a non-static @Bean method with a BeanDefinitionRegistryPostProcessor " +
                            "return type: Consider declaring such methods as 'static'."); } configBeanDefs.put(beanName, (AbstractBeanDefinition) beanDef);  //存放标注了Configuration注解的beanDefinition } } if (configBeanDefs.isEmpty()) { 
            return; } ConfigurationClassEnhancer enhancer = new ConfigurationClassEnhancer(); for (Map.Entry<String, AbstractBeanDefinition> entry : configBeanDefs.entrySet()) { AbstractBeanDefinition beanDef = entry.getValue(); // If a @Configuration class gets proxied, always proxy the target class
 beanDef.setAttribute(AutoProxyUtils.PRESERVE_TARGET_CLASS_ATTRIBUTE, Boolean.TRUE); try {
                Class<?> configClass = beanDef.resolveBeanClass(this.beanClassLoader); if (configClass != null) { Class<?> enhancedClass = enhancer.enhance(configClass, this.beanClassLoader); 
　　　　　　　　　　 //生成AppConfig1的子类CGLIB代理Class 并且在下面将beanDef类型更改为了该CGLIB class if (configClass != enhancedClass) { if (logger.isTraceEnabled()) { logger.trace(String.format("Replacing bean definition '%s' existing class '%s' with " +
                                    "enhanced class '%s'", entry.getKey(), configClass.getName(), enhancedClass.getName())); } beanDef.setBeanClass(enhancedClass); } } } catch (Throwable ex) { throw new IllegalStateException("Cannot load configuration class: " + beanDef.getBeanClassName(), ex); } } }

 1 private Enhancer newEnhancer(Class<?> configSuperClass, @Nullable ClassLoader classLoader) {  2         Enhancer enhancer = new Enhancer();  3  enhancer.setSuperclass(configSuperClass);　　　　　　　　　　　　　　　　　　//被代理的父类类型设置上去就是AppConfig1  4         enhancer.setInterfaces(new Class<?>[] {EnhancedConfiguration.class}); 　　
　　　　//被代理的接口只设置了EnhancedConfiguration，只是为了给CGLIB子类能够设置上BeanFactory属性  5         enhancer.setUseFactory(false);  6  enhancer.setNamingPolicy(SpringNamingPolicy.INSTANCE);  7         enhancer.setStrategy(new BeanFactoryAwareGeneratorStrategy(classLoader));  8  enhancer.setCallbackFilter(CALLBACK_FILTER);  9  enhancer.setCallbackTypes(CALLBACK_FILTER.getCallbackTypes()); 10         return enhancer; 11     }

1 private Class<?> createClass(Enhancer enhancer) { 2         Class<?> subclass = enhancer.createClass(); 3         // Registering callbacks statically (as opposed to thread-local) 4         // is critical for usage in an OSGi environment (SPR-5932)...
5  Enhancer.registerStaticCallbacks(subclass, CALLBACKS); //CALLBACKS对象在上面图片里 6         return subclass; 7     }

1 public int accept(Method method) { 2             for (int i = 0; i < this.callbacks.length; i++) { 3                 Callback callback = this.callbacks[i]; 4                 if (!(callback instanceof ConditionalCallback) || ((ConditionalCallback) callback).isMatch(method)) { 5                     return i; 6 } 7 } 8             throw new IllegalStateException("No callback available for method " + method.getName()); 9         }

　　　　　@Override public boolean isMatch(Method candidateMethod) { return (candidateMethod.getDeclaringClass() != Object.class &&
                    !BeanFactoryAwareMethodInterceptor.isSetBeanFactory(candidateMethod) && BeanAnnotationHelper.isBeanAnnotated(candidateMethod)); 
　　　　//方法不是Object中定义的，且不是setBeanFactory方法，且该方法包含@Bean注解就返回true }

 1 public Object intercept(Object enhancedConfigInstance, Method beanMethod, Object[] beanMethodArgs,  2                     MethodProxy cglibMethodProxy) throws Throwable {  3 
 4             ConfigurableBeanFactory beanFactory = getBeanFactory(enhancedConfigInstance);            
　　　　　　　　// 通过反射从CGLIB增强的对象获取beanFactory对象
 5             String beanName = BeanAnnotationHelper.determineBeanNameFor(beanMethod);    // 得到beanName值，默认为方法名字，可以通过@Bean注解指定  6       
 8             if (BeanAnnotationHelper.isScopedProxy(beanMethod)) {                        // 解析Scope注解
 9                 String scopedBeanName = ScopedProxyCreator.getTargetBeanName(beanName); 10                 if (beanFactory.isCurrentlyInCreation(scopedBeanName)) { 11                     beanName = scopedBeanName; 12  } 13  }
　　　　　　　　　//FactoryBean类型的Bean解析方式，暂不分析
22             if (factoryContainsBean(beanFactory, BeanFactory.FACTORY_BEAN_PREFIX + beanName) &&           
23  factoryContainsBean(beanFactory, beanName)) { 24                 Object factoryBean = beanFactory.getBean(BeanFactory.FACTORY_BEAN_PREFIX + beanName); 25                 if (factoryBean instanceof ScopedProxyFactoryBean) { 26                     // Scoped proxy factory beans are a special case and should not be further proxied
27  } 28                 else { 29                     // It is a candidate FactoryBean - go ahead with enhancement
30                     return enhanceFactoryBean(factoryBean, beanMethod.getReturnType(), beanFactory, beanName); 31  } 32  } 33 
34             if (isCurrentlyInvokedFactoryMethod(beanMethod)) {        
　　　　　　　　//判断当前执行的方法是否是正在执行的@Bean的方法,getMan2中调用getMan方法,getMan含有@Bean 这时候就返回false
38                 if (logger.isInfoEnabled() &&
39                         BeanFactoryPostProcessor.class.isAssignableFrom(beanMethod.getReturnType())) { 40                     logger.info(String.format("@Bean method %s.%s is non-static and returns an object " +
41                                     "assignable to Spring's BeanFactoryPostProcessor interface. This will " +
42                                     "result in a failure to process annotations such as @Autowired, " +
43                                     "@Resource and @PostConstruct within the method's declaring " +
44                                     "@Configuration class. Add the 'static' modifier to this method to avoid " +
45                                     "these container lifecycle issues; see @Bean javadoc for complete details.", 46  beanMethod.getDeclaringClass().getSimpleName(), beanMethod.getName())); 47  } 48                 return cglibMethodProxy.invokeSuper(enhancedConfigInstance, beanMethodArgs);　　　　 //getMan方法直接反射可以得到对象 49  } 50 
51             return resolveBeanReference(beanMethod, beanMethodArgs, beanFactory, beanName);            //在getMan2中调用getMan方法就会执行这段逻辑
52         

1 private boolean isCurrentlyInvokedFactoryMethod(Method method) { 2             Method currentlyInvoked = SimpleInstantiationStrategy.getCurrentlyInvokedFactoryMethod();
　　　　　　　　//获取ThreadLocalcurrentlyInvokedFactoryMethod对象currentlyInvokedFactoryMethod中当前的Method 3             return (currentlyInvoked != null && method.getName().equals(currentlyInvoked.getName()) &&
4  Arrays.equals(method.getParameterTypes(), currentlyInvoked.getParameterTypes())); 5         }

 1 private Object resolveBeanReference(Method beanMethod, Object[] beanMethodArgs,  2  ConfigurableBeanFactory beanFactory, String beanName) {  3 
 8             boolean alreadyInCreation = beanFactory.isCurrentlyInCreation(beanName); //getMan并不是正在创建的bean,false  9             try { 10                 if (alreadyInCreation) { 11                     beanFactory.setCurrentlyInCreation(beanName, false); 12  } 13                 boolean useArgs = !ObjectUtils.isEmpty(beanMethodArgs); 14                 if (useArgs && beanFactory.isSingleton(beanName)) {                 
18                     for (Object arg : beanMethodArgs) { 19                         if (arg == null) { 20                             useArgs = false; 21                             break; 22  } 23  } 24  } 25                 Object beanInstance = (useArgs ? beanFactory.getBean(beanName, beanMethodArgs) : 26  beanFactory.getBean(beanName));　　　　　　　　　　　　　　　　　　　　　　　　　　//没有参数的情况下，直接getBean获取就可以了 27                 if (!ClassUtils.isAssignableValue(beanMethod.getReturnType(), beanInstance)) { 28                     if (beanInstance.equals(null)) { 29                         if (logger.isDebugEnabled()) { 30                             logger.debug(String.format("@Bean method %s.%s called as bean reference " +
31                                     "for type [%s] returned null bean; resolving to null value.", 32  beanMethod.getDeclaringClass().getSimpleName(), beanMethod.getName(), 33  beanMethod.getReturnType().getName())); 34  } 35                         beanInstance = null; 36  } 37                     else { 38                         String msg = String.format("@Bean method %s.%s called as bean reference " +
39                                 "for type [%s] but overridden by non-compatible bean instance of type [%s].", 40  beanMethod.getDeclaringClass().getSimpleName(), beanMethod.getName(), 41  beanMethod.getReturnType().getName(), beanInstance.getClass().getName()); 42                         try { 43                             BeanDefinition beanDefinition = beanFactory.getMergedBeanDefinition(beanName); 44                             msg += " Overriding bean of same name declared in: " + beanDefinition.getResourceDescription(); 45  } 46                         catch (NoSuchBeanDefinitionException ex) { 47                             // Ignore - simply no detailed message then.
48  } 49                         throw new IllegalStateException(msg); 50  } 51  } 52                 Method currentlyInvoked = SimpleInstantiationStrategy.getCurrentlyInvokedFactoryMethod();　　　　//当前ThreadLocal中的是getMan2 53                 if (currentlyInvoked != null) { 54                     String outerBeanName = BeanAnnotationHelper.determineBeanNameFor(currentlyInvoked); 55  beanFactory.registerDependentBean(beanName, outerBeanName);　　　　　　　　　　　　　　　　　　　//设置依赖关系 56  } 57                 return beanInstance; 58  } 59             finally { 60                 if (alreadyInCreation) { 61                     beanFactory.setCurrentlyInCreation(beanName, true); 62  } 63  } 64         }

1 　　AnnotationConfigApplicationContext ac = new AnnotationConfigApplicationContext(AppConfig1.class); 2         AppConfig1 config = ac.getBean(AppConfig1.class); 3         Field[] fs = config.getClass().getFields(); 4         for (Field field : fs) { 5  System.out.println(field.getName()); 6         }