Question

AppConfig包含Java配置。

package com.wh;

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.EnableLoadTimeWeaving;
import org.springframework.context.annotation.EnableLoadTimeWeaving.AspectJWeaving;
import org.springframework.context.annotation.Lazy;
import org.springframework.context.annotation.aspectj.EnableSpringConfigured;

@Configuration
@EnableSpringConfigured
@EnableLoadTimeWeaving(aspectjWeaving=AspectJWeaving.ENABLED)
public class AppConfig {

    @Bean
    @Lazy
    public EchoService echoService(){

          return new EchoService();
    }
@Bean
    public InstrumentationLoadTimeWeaver loadTimeWeaver()  throws Throwable {
    InstrumentationLoadTimeWeaver loadTimeWeaver = new InstrumentationLoadTimeWeaver();
    return loadTimeWeaver;
    }
}

服务类

package com.wh;

import org.springframework.stereotype.Service;

@Service
public class EchoService {
    public void echo( String s ) {
        System.out.println( s );
    }
}

EchoDelegateService是Non Bean类，我们在其中使用Autowired所需的Bean。我们希望EchoService可以自动连接。

问题：EchoService未获得自动装配。给出空指针异常。

package com.wh;

import org.springframework.beans.factory.annotation.Autowire;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Configurable;

@Configurable( preConstruction = true, autowire = Autowire.BY_TYPE, dependencyCheck = false )
public class EchoDelegateService {
    @Autowired
    private EchoService echoService;

    public void echo( String s ) {
        echoService.echo( s );
    }
}

我们正在调用NonBean类的方法的主类。

package com.wh;

import org.springframework.context.ApplicationContext;
import org.springframework.context.annotation.AnnotationConfigApplicationContext;

public class MainApp {
    public static void main(String[] args) {
          ApplicationContext ctx = 
          new AnnotationConfigApplicationContext(AppConfig.class);

          new EchoDelegateService().echo("hihi, it works...");
       }
}

Answer 1

你的问题已经包含了答案：“......在非豆类中”。这根本行不通。所有自动装配，方面解决以及任何内容，仅适用于bean。因此，您肯定需要通过spring factory构建您的EchoDelegateService：

EchoDelegateService myService = ctx.getBean(EchoDelegateService.class);
myService.echo("this should really work now");

使用AspectJ在非Bean类中自动装配

1 个答案: