Spring Boot-接口和实现 [英] Spring Boot - interfaces and implementations

问题描述

Java/Spring新手在这里.我有一个关于通过SpringBoot自动接线的问题.

Java/Spring newbie here. I've a question about auto wiring through SpringBoot.

我有一个接口，一个实现，一个主类和一个配置类，就像这样:

I have an interface , an implementation , a main class and a configuration class like so :

ServiceInterface.java

ServiceInterface.java

public interface ServiceInterface {
    static String serviceName = "service";
    public void displayMessage();
    public String getServiceName(); 
}

ServiceImpl1.java

ServiceImpl1.java

public class ServiceImpl1 implements ServiceInterface{
    static String serviceName = "default service value ";

    public String getServiceName() {
        return serviceName;
    }

@Override
public void displayMessage()
    {
        System.out.println("This is implementation 1");
    }
}

主要班级:

@SpringBootApplication
public class App implements CommandLineRunner{

@Autowired
private ServiceInterface serviceInterface;

public static void main(String args[])
{
    SpringApplication.run(App.class, args);

}

@Override
public void run(String... args) {
    serviceInterface.displayMessage();
    System.out.println(serviceInterface.getServiceName());
    System.out.println(serviceInterface.serviceName );
}
}

AppConfig.java

AppConfig.java

@Configuration
public class AppConfig {

@Bean
ServiceInterface serviceInterface()
{
    return new ServiceImpl1();
}
}

运行代码时，我将其作为输出

When I run the code , I get this as the output

This is implementation 1
service 1 
default service value

为什么ServiceImpl1实现中的变量'serviceName'无法通过Spring通过自动装配创建的对象访问?

Why is the variable 'serviceName' inside ServiceImpl1 implementation not accessible through the object created by Spring through autowiring ?

推荐答案

没关系..我刚刚发现

Never mind.. I just figured out that variables declared inside an interface are static and final.

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