使用JSR330提供程序时，Threaded Bean在Spring中不会自动获得环境@Autowired [英] Threaded Beans doesn't get Environment @Autowired to them in Spring when using JSR330 Provider
问题描述
希望这个问题可以自我解释
Hope the Question is self explanatory
ClassA.java
@Component
@Scope(ConfigurableBeanFactory.SCOPE_PROTOTYPE)
public class ClassA implements InterB {
private static int counter=0;
private int objectid = 0;
@Autowired
InterA abcd;
public ClassA() {
super();
this.objectid = ++counter;
}
@Override
public void dododo() {
System.out.println("instance number "+objectid++);
abcd.doit();
}
}
ClassB.java
@Component
@Conditional(OracleDBEngineCondition.class)
public class ClassB extends DummyParent implements InterA {
@Autowired
private Environment env;
@Override
public void doit() {
System.out.println("hoo hoo" +" -- "+env.getProperty("DBENGINE"));
}
}
ClassC.java
@Component("classc")
public class ClassC implements Runnable {
@Autowired
Provider<InterB> classAPrototypeobj;
public void doFromAbove() {
InterB cls = (InterB) classAPrototypeobj.get();
InterB cls1 = (InterB) classAPrototypeobj.get();
cls.dododo();
cls1.dododo();
System.out.println(cls);
System.out.println(cls1);
}
@Override
public void run() {
this.doFromAbove();
}
}
ClassConfig.java
@Configuration
@ComponentScan
public class ClassConfig {
}
主要方法
public static void main(String[] args) {
ClassC obj;
try(AbstractApplicationContext appctx = new AnnotationConfigApplicationContext(ClassConfig.class)) {
obj = (ClassC) appctx.getBean("classc");
}
Thread objThread = new Thread(obj);
objThread.start();
}
更新的主要方法(仍然存在相同的问题)
public static void main(String[] args) {
try(AbstractApplicationContext appctx = new AnnotationConfigApplicationContext(ClassConfig.class)) {
ClassC obj = (ClassC) appctx.getBean("classc");
Thread objThread = new Thread(obj);
objThread.start();
}
}
执行时，这会导致NoSuchBeanDefinitionException豆的环境"
When Executed, This Causes NoSuchBeanDefinitionException for the bean 'environment'
但是，当我们在Config类中定义以下内容时，该错误将消失而无任何痕迹. 这是解决方法(但应该由Spring自动注入环境，我们不应该这样做).不知道有多少豆没有被注入/@Autowired
But when we define the following in our Config Class, the error vanishes without a trace. This is the Workaround(but Spring's supposed to inject Environment automagically we shouldn't do this). Not sure how many such beans are not injected/@Autowired
@Bean
public Environment environment(ApplicationContext context) {
return context.getEnvironment();
}
我怀疑这是一个Spring Framework错误...不是吗?
I Suspect this is a Spring Framework Bug... Is it not?
StackTrace:
Exception in thread "Thread-1" org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'classA': Unsatisfied dependency expressed through field 'abcd'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'classB': Injection of autowired dependencies failed; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No bean named 'environment' available
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:588)
at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:88)
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:366)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1264)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:553)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:483)
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:325)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:202)
at org.springframework.beans.factory.config.DependencyDescriptor.resolveCandidate(DependencyDescriptor.java:208)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1138)
at org.springframework.beans.factory.support.DefaultListableBeanFactory$DependencyObjectProvider.getObject(DefaultListableBeanFactory.java:1630)
at org.springframework.beans.factory.support.DefaultListableBeanFactory$Jsr330DependencyProvider.get(DefaultListableBeanFactory.java:1699)
at tpt.verifypoc.ClassC.doFromAbove(ClassC.java:28)
at tpt.verifypoc.ClassC.run(ClassC.java:39)
at java.lang.Thread.run(Thread.java:745)
Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'classB': Injection of autowired dependencies failed; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No bean named 'environment' available
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:372)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1264)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:553)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:483)
at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:306)
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230)
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:302)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:202)
at org.springframework.beans.factory.config.DependencyDescriptor.resolveCandidate(DependencyDescriptor.java:208)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1138)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1066)
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:585)
... 14 more
Caused by: org.springframework.beans.factory.NoSuchBeanDefinitionException: No bean named 'environment' available
at org.springframework.beans.factory.support.DefaultListableBeanFactory.getBeanDefinition(DefaultListableBeanFactory.java:687)
at org.springframework.beans.factory.support.AbstractBeanFactory.getMergedLocalBeanDefinition(AbstractBeanFactory.java:1207)
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:284)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:202)
at org.springframework.beans.factory.config.DependencyDescriptor.resolveCandidate(DependencyDescriptor.java:208)
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$ShortcutDependencyDescriptor.resolveShortcut(AutowiredAnnotationBeanPostProcessor.java:740)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1077)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1066)
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.resolvedCachedArgument(AutowiredAnnotationBeanPostProcessor.java:548)
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.access$200(AutowiredAnnotationBeanPostProcessor.java:117)
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:577)
at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:88)
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:366)
... 25 more
注意:
- 春季:4.3.9.发布
- JSR330:javax.inject版本1
推荐答案
在开始使用要关闭ApplicationContext的对象之前，我想说这不是Spring中查看代码的错误.或者实际上，您拥有的try-with-resources块可以做到这一点.
I would say this isn't a bug in Spring looking at your code before you start to use the objects you are closing the ApplicationContext. Or actually the try-with-resources block you have does that.
public static void main(String[] args) {
ClassC obj;
try(AbstractApplicationContext appctx = new AnnotationConfigApplicationContext(ClassConfig.class)) {
obj = (ClassC) appctx.getBean("classc");
}
Thread objThread = new Thread(obj);
objThread.start();
}
与
public static void main(String[] args) {
ClassC obj;
AbstractApplicationContext appctx = new AnnotationConfigApplicationContext(ClassConfig.class)) {
obj = (ClassC) appctx.getBean("classc");
appctx.close();
Thread objThread = new Thread(obj);
objThread.start();
}
在使用对象之前，您要关闭ApplicationContext.剩下的是ClassC的实例，其中包含Provided<ClassB>的半备份代理，需要上下文来查找某些bean.但是，当您从注册表下面提取注册表时，它无法查找这些bean.
You are closing the ApplicationContext before you are using the objects. What remains is an instanceof ClassC with a half backed proxy of Provided<ClassB> which needs to context to lookup certain beans. However it has no-way of looking up those beans as you pulled the registry from underneath it.
当您关闭ApplicationContext时，您正在关闭您的应用程序.我希望您仍然存在的对象现在无效，因为属于该对象的容器被破坏了.
When you are closing the ApplicationContext you are shutting down your application. I would expect that your objects that still live are now invalid, because the container the belong to is destroyed.
将代码与JDBC代码进行比较.您正在打开Connection，关闭连接，然后尝试在关闭的连接上准备语句. JDBC不允许这样做，因为Connection已关闭，因此无效.
Compare the code to JDBC code. You are opening a Connection, close the connection and afterwards try to prepare a statement on a closed connection. JDBC won't allow this because the Connection is closed and thus invalid.
将其与Microsoft Excel进行比较，将其打开，在Sheet中工作，编写宏.关闭excel并期望宏仍然运行.
Compare it to Microsoft Excel, you open it, work in a Sheet, write a macro. Close excel and expect the macro still to run.
这篇关于使用JSR330提供程序时，Threaded Bean在Spring中不会自动获得环境@Autowired的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
