为什么MyBatis和Spring自动装载我的Mapper？(Why is my Spring Boot @Autowired MyBatis static mapper null?)

 我有以下类，但Spring和MyBatis-Spring-Boot-Starter不会自动连接我的映射器。 
 
 当我运行请求时，我得到了println()的输出 
 
sourceMapper = null
 
 类 
 
package ...model;

import java.net.MalformedURLException;
import java.net.URL;
import java.util.Date;
import org.springframework.beans.factory.annotation.Autowired;
import ...mapper.SourceMapper;

public class Source {

    public long id;
    public String host;
    public Date created_at;

    @Autowired
    public static SourceMapper sourceMapper;   #### Why isn't this set?

    public static Source findOrCreate(String url) {
        Source source = null;
        String host = "NONE";
        if (url != null) {
            // extract only the domain
            try {
                URL urlObj = new URL(url);
                host = urlObj.getHost();
            } catch (MalformedURLException e) { } // ignore
        }
        System.out.println("sourceMapper = " + sourceMapper);
        source = sourceMapper.findByHost(host);
        if (source == null) {
            long newId = sourceMapper.create(host);
            source = sourceMapper.findById(newId);
        }
        return source;
    }

}
 
 我尽可能接近这些例子。 
 
 http://www.mybatis.org/spring-boot-starter/mybatis-spring-boot-autoconfigure/ 
 
 处理请求的主@Controller类中的其他@Autowired Mappers工作，即使它们是私有的。 
 
 这是Mapper类 
 
package ...mapper;

@Mapper
public interface SourceMapper {
  ...
 
 MyBatis 3.4.5，MyBatis Spring 1.3.1，MyBatis Spring Boot Autoconfigure 1.3.1，MyBatis Spring Boot Starter 1.3.1 

I have the following class, but Spring and MyBatis-Spring-Boot-Starter will not autowire my mapper. 
 
When I run the request, I get the output from the println()
 
sourceMapper = null
 
Model
 
public class Source {       
    @Autowired
    public static SourceMapper sourceMapper;   #### Why isn't this set?

    public static Source findOrCreate(String url) {
        ...
        System.out.println("sourceMapper = " + sourceMapper);
        source = sourceMapper.findByHost(host);
        ...
    }

}
 
I followed the examples as closely as possible.
 
http://www.mybatis.org/spring-boot-starter/mybatis-spring-boot-autoconfigure/
 
The other @Autowired Mappers in the main @Controller class that handles requests work, even though they are private.
 
This is the Mapper class
 
package ...mapper;

@Mapper
public interface SourceMapper {
  ...
 
 
I ran into this issue again with a new model and mapper. I tried to follow Why is my Spring @Autowired field null? and the code sample, but it was still null! I tried @Configurable, @Service, @Component.
 
Model 
@Configurable
public class Domain {
    @Autowired
    private static DomainMapper domainMapper;

    public static void incrementCounter(String host) {
        ...
        Domain d = getDomainMapper().find(host, thisMonth);

    public static DomainMapper getDomainMapper() {
        return domainMapper;

    public static void setDomainMapper(DomainMapper domainMapper) {
        Domain.domainMapper = domainMapper;
 
Mapper 
@Mapper
public interface DomainMapper {
 
MyBatis 3.4.5, MyBatis Spring 1.3.1, MyBatis Spring Boot Autoconfigure 1.3.1, MyBatis Spring Boot Starter 1.3.1

原文：https://stackoverflow.com/questions/50283388