春季4&x2B；使用Java8的MyBatis集成问题

在使用Java8（1.8.060）、Spring4.2.1和MyBatis3.3.0时，我面临以下异常

Sep 29, 2015 11:02:58 AM org.springframework.context.annotation.AnnotationConfigApplicationContext prepareRefresh
INFO: Refreshing org.springframework.context.annotation.AnnotationConfigApplicationContext@246b179d: startup date [Tue Sep 29 11:02:58 EDT 2015]; root of context hierarchy
Sep 29, 2015 11:02:58 AM org.mybatis.spring.mapper.ClassPathMapperScanner checkCandidate
WARNING: Skipping MapperFactoryBean with name 'userMapper' and 'com.poc.test.spring4app.mapper.UserMapper' mapperInterface. Bean already defined with the same name!
Sep 29, 2015 11:02:58 AM org.mybatis.spring.mapper.ClassPathMapperScanner doScan
WARNING: No MyBatis mapper was found in '[com.poc.test.spring4app.mapper]' package. Please check your configuration.
Creating tables
Sep 29, 2015 11:02:59 AM org.springframework.context.annotation.AnnotationConfigApplicationContext refresh
WARNING: Exception encountered during context initialization - cancelling refresh attempt
org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'userMapper' defined in com.poc.test.spring4app.config.AppConfiguration: Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [com.poc.test.spring4app.mapper.UserMapper]: Factory method 'userMapper' threw exception; nested exception is org.apache.ibatis.binding.BindingException: Type interface com.poc.test.spring4app.mapper.UserMapper is not known to the MapperRegistry.
    at org.springframework.beans.factory.support.ConstructorResolver.instantiateUsingFactoryMethod(ConstructorResolver.java:599)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateUsingFactoryMethod(AbstractAutowireCapableBeanFactory.java:1123)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1018)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:510)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:482)
    at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:305)
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230)
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:301)
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:196)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:772)
    at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:834)
    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:537)
    at org.springframework.context.annotation.AnnotationConfigApplicationContext.<init>(AnnotationConfigApplicationContext.java:84)
    at com.poc.test.spring4app.config.AppInitializer.main(AppInitializer.java:16)
Caused by: org.springframework.beans.BeanInstantiationException: Failed to instantiate [com.poc.test.spring4app.mapper.UserMapper]: Factory method 'userMapper' threw exception; nested exception is org.apache.ibatis.binding.BindingException: Type interface com.poc.test.spring4app.mapper.UserMapper is not known to the MapperRegistry.
    at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:189)
    at org.springframework.beans.factory.support.ConstructorResolver.instantiateUsingFactoryMethod(ConstructorResolver.java:588)
    ... 13 more
Caused by: org.apache.ibatis.binding.BindingException: Type interface com.poc.test.spring4app.mapper.UserMapper is not known to the MapperRegistry.
    at org.apache.ibatis.binding.MapperRegistry.getMapper(MapperRegistry.java:47)
    at org.apache.ibatis.session.Configuration.getMapper(Configuration.java:675)
    at org.mybatis.spring.SqlSessionTemplate.getMapper(SqlSessionTemplate.java:293)
    at com.poc.test.spring4app.config.AppConfiguration.userMapper(AppConfiguration.java:51)
    at com.poc.test.spring4app.config.AppConfiguration$$EnhancerBySpringCGLIB$$8dd4b125.CGLIB$userMapper$0(<generated>)
    at com.poc.test.spring4app.config.AppConfiguration$$EnhancerBySpringCGLIB$$8dd4b125$$FastClassBySpringCGLIB$$677c8295.invoke(<generated>)
    at org.springframework.cglib.proxy.MethodProxy.invokeSuper(MethodProxy.java:228)
    at org.springframework.context.annotation.ConfigurationClassEnhancer$BeanMethodInterceptor.intercept(ConfigurationClassEnhancer.java:318)
    at com.poc.test.spring4app.config.AppConfiguration$$EnhancerBySpringCGLIB$$8dd4b125.userMapper(<generated>)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:497)
    at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:162)
    ... 14 more

用户映射器

package com.poc.test.spring4app.config;

import java.util.List;

import org.springframework.context.annotation.AnnotationConfigApplicationContext;
import org.springframework.context.support.AbstractApplicationContext;

import com.poc.test.spring4app.domain.User;
import com.poc.test.spring4app.mapper.UserMapper;

public class AppInitializer {

    public static void main(String[] args) {
        AbstractApplicationContext context = null;
        try {
            context = new AnnotationConfigApplicationContext(
                    AppConfiguration.class);
            context.registerShutdownHook();
            UserMapper userMapper = context.getBean(UserMapper.class);
            List<User> users = userMapper.getAllUsers();
            System.out.println(users.toString());
            context.close();
        }
        catch (final Exception e) {
            if (context != null) {
                context.close();
            }
        }
    }
}

package com.poc.test.spring4app.mapper;

import java.util.List;

import org.apache.ibatis.annotations.Result;
import org.apache.ibatis.annotations.Results;
import org.apache.ibatis.annotations.Select;

import com.poc.test.spring4app.domain.User;

public interface UserMapper {

    @Select("select id, firstName, lastName, email from users")
    @Results(value={
            @Result(column="id", property="id"),
            @Result(column="firstName", property="firstName"),
            @Result(column="lastName", property="lastName"),
            @Result(column="email", property="email")
    })
    List<User> getAllUsers();

}

package com.poc.test.spring4app.domain;

import java.io.Serializable;

public class User implements Serializable {

    private static final long serialVersionUID = 1L;
    private long id;
    private String firstName;
    private String lastName;
    private String email;
    /**
     * @return the id
     */
    public long getId() {
        return id;
    }
    /**
     * @param id the id to set
     */
    public void setId(long id) {
        this.id = id;
    }
    /**
     * @return the firstName
     */
    public String getFirstName() {
        return firstName;
    }
    /**
     * @param firstName the firstName to set
     */
    public void setFirstName(String firstName) {
        this.firstName = firstName;
    }
    /**
     * @return the lastName
     */
    public String getLastName() {
        return lastName;
    }
    /**
     * @param lastName the lastName to set
     */
    public void setLastName(String lastName) {
        this.lastName = lastName;
    }
    /**
     * @return the email
     */
    public String getEmail() {
        return email;
    }
    /**
     * @param email the email to set
     */
    public void setEmail(String email) {
        this.email = email;
    }

    // getters and setters

 }

---

我相信这可能是你的问题：

 WARNING: Skipping MapperFactoryBean with name 'userMapper' and  'com.poc.test.spring4app.mapper.UserMapper' mapperInterface. Bean already defined with the same name!

试着消除这种两面性

问题的解决方案：

---

使用Spring4和MyBatis3，如果您已经在@MapperScan上扫描MyBatisMapper实现，则不应该显式定义映射器。bean的实例化是自动处理的。

我们使用Java 8、Spring 4、Spring引导以及最新的MyBatis和MyBatis Spring。此堆栈工作正常。显示代码。@luboskrnac我用代码更新了问题。提前谢谢。谢谢你把它指向卢博斯克纳克！这个POC有帮助；我的实际应用程序中的Spring警告被抑制；很可能错过了。但是你知道为什么它在Spring3.x中工作而不是在Spring4中吗？对不起，没有线索，没有机会在Spring3中使用MyBatis。在我的春季三天里使用了不同的库。

package com.poc.test.spring4app.domain;

import java.io.Serializable;

public class User implements Serializable {

    private static final long serialVersionUID = 1L;
    private long id;
    private String firstName;
    private String lastName;
    private String email;
    /**
     * @return the id
     */
    public long getId() {
        return id;
    }
    /**
     * @param id the id to set
     */
    public void setId(long id) {
        this.id = id;
    }
    /**
     * @return the firstName
     */
    public String getFirstName() {
        return firstName;
    }
    /**
     * @param firstName the firstName to set
     */
    public void setFirstName(String firstName) {
        this.firstName = firstName;
    }
    /**
     * @return the lastName
     */
    public String getLastName() {
        return lastName;
    }
    /**
     * @param lastName the lastName to set
     */
    public void setLastName(String lastName) {
        this.lastName = lastName;
    }
    /**
     * @return the email
     */
    public String getEmail() {
        return email;
    }
    /**
     * @param email the email to set
     */
    public void setEmail(String email) {
        this.email = email;
    }

    // getters and setters

 }

 WARNING: Skipping MapperFactoryBean with name 'userMapper' and  'com.poc.test.spring4app.mapper.UserMapper' mapperInterface. Bean already defined with the same name!