Question

我得到＆＃34; org.springframework.beans.factory.NoSuchBeanDefinitionException：没有名为＆＃39;员工＆＃39;已定义＆＃34;错误，我不知道我做错了什么。请在下面找到代码。

）AppConfig类：

@ComponentScan("com.spring.annotation.propertyconfigurer")
@Configuration
@PropertySource("classpath:employee.properties")
public class AppConfig {

@Bean
public static PropertySourcesPlaceholderConfigurer    propertySourcesPlaceholderConfigurer() {
    return new PropertySourcesPlaceholderConfigurer();
 }    
}

2）员工类

@Component("employee")
public class Employee {

    @Value("${emp.empId}")
    private int empId;
    @Value("${emp.name}")
    private String name;
    @Autowired
    private Address address;

    public int getEmpId() {
        return empId;
    }

    public void setEmpId(int empId) {
        this.empId = empId;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public Address getAddress() {
        return address;
    }

    public void setAddress(Address address) {
        this.address = address;
    }

    public void print() {
        System.out.println("Employee Id -> " + empId);
        System.out.println("Employee Name -> " + name);
        System.out.println("Employee Address -> [ " + address.getCity() + "," + getAddress().getCountry() + "]");
    }
}

3）地址类：

@Component("address")
public class Address {

    private String city;
    private String country;

    public String getCity() {
        return city;
    }

    public void setCity(String city) {
        this.city = city;
    }

    public String getCountry() {
        return country;
    }

    public void setCountry(String country) {
        this.country = country;
    }
}

4）主类

public class PropertyConfigurerApp {

    public static void main(String[] args) {
        try (AbstractApplicationContext context = new AnnotationConfigApplicationContext("AppConfig.class")) {
            Employee employee = (Employee) context.getBean("employee");
            employee.print();

        } catch (Exception e) {
            e.printStackTrace();
        }

    }

}

请帮我解决此问题。

谢谢，哈拉

Answer 1

您可以将bean注册到配置中，例如在组件包上使用组件扫描。

有几种方法可以做到这一点

via xml config <context:component-scan base-package="org.example"/>
在@ComponentScan({package1, .., package n})

@Configuration

您还可以在@Bean

中为@Components添加@Configuration

参见spring文档

http://docs.spring.io/spring/docs/current/spring-framework-reference/htmlsingle

http://docs.spring.io/spring/docs/current/spring-framework-reference/htmlsingle/#beans-annotation-config

如何更改您的代码

1-给你的课程一个包（如果你还没有）。我使用了test.component作为员工和地址

2-在AppConfig中更改

     @ComponentScan("com.spring.annotation.propertyconfigurer")

与

    @ComponentScan("test.component")

或

    @ComponentScan(basePackages={"test.component"})

3-在propertyConfigurerApp中更改

            AbstractApplicationContext context = new AnnotationConfigApplicationContext("AppConfig.class")

与

  AbstractApplicationContext context = new AnnotationConfigApplicationContext(AppConfig.class)

它应该工作（将你的employee.properties放在classpath的根目录上）

但是，您并不需要制作所有这些组件扫描内容，因为您不会在示例中使用自动装配。

使用AnnotationConfigApplicationContext的NoSuchBeanDefinitionException异常

1 个答案: