throw UnsupportedOperationException: null while using mybatis

Question

I'm writing a spring-boot application with mybatis-plus(It is fully compatible with mybatis).

EmployeeMapper.xml:

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper
        PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
        "https://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.easyauth.mapper.EmployeeMapper">

    <resultMap id="EmployeeWithRolesMap" type="com.easyauth.domain.entity.Employee">
        <id column="id" property="id"/>
        <result column="username" property="username"/>
        <result column="password" property="password"/>
        <result column="email" property="email"/>
        <result column="last_login" property="lastLogin"/>
        <result column="register_time" property="registerTime"/>
        <result column="status" property="status"/>
        <collection property="rolesId" ofType="java.lang.Long" column="id" select="selectRolesByEmployeeId"/>
    </resultMap>

    <select id="selectRolesByEmployeeId" resultType="java.lang.Long">
        SELECT role_id
        FROM employee_role
        WHERE employee_id = #{id}
    </select>

    <select id="pageWithRolesId" resultMap="EmployeeWithRolesMap">
        SELECT DISTINCT e.*
        FROM employee e
        LEFT JOIN employee_role er ON e.id = er.employee_id
        <where>
            <if test="dto.username != null and dto.username != ''">
                AND e.username LIKE CONCAT('%', #{dto.username}, '%')
            </if>
            <if test="dto.email != null and dto.email != ''">
                AND e.email LIKE CONCAT('%', #{dto.email}, '%')
            </if>
            <!-- RolesId一定不为空，查找包含dto中角色集合的员工 -->
            AND er.role_id IN
            <foreach collection="dto.roleIds" item="roleId" open="(" separator="," close=")">
                #{roleId}
            </foreach>
            GROUP BY e.id
            HAVING COUNT(DISTINCT er.role_id) = #{dto.roleIds.size()}
        </where>
    </select>

</mapper>

Employee.java:

@Data
@TableName("employee")
public class Employee {
    @TableId(value = "id", type = IdType.AUTO)
    private Long id;
    private String username;
    private String password;
    private String email;
    private LocalDateTime lastLogin;
    private LocalDateTime registerTime;
    private Long status;

    @TableField(exist = false)
    private List<Long> rolesId;
}

in EmployeeMapper.java:

List<Employee> pageWithRolesId(@Param("dto") EmployeePageQueryDTO queryDTO);

input param: EmployeePageQueryDTO(current=1, size=10, username=null, email=null, roleIds=[2, 4])

output:

java.lang.UnsupportedOperationException: null at org.apache.ibatis.reflection.wrapper.CollectionWrapper.get(CollectionWrapper.java:38) ~[mybatis-3.5.15.jar:3.5.15] at org.apache.ibatis.reflection.MetaObject.getValue(MetaObject.java:116) ~[mybatis-3.5.15.jar:3.5.15] at org.apache.ibatis.reflection.MetaObject.getValue(MetaObject.java:122) ~[mybatis-3.5.15.jar:3.5.15] at org.apache.ibatis.reflection.MetaObject.getValue(MetaObject.java:122) ~[mybatis-3.5.15.jar:3.5.15] at org.apache.ibatis.executor.BaseExecutor.createCacheKey(BaseExecutor.java:225) ~[mybatis-3.5.15.jar:3.5.15] at org.apache.ibatis.executor.CachingExecutor.createCacheKey(CachingExecutor.java:149) ~[mybatis-3.5.15.jar:3.5.15] at com.baomidou.mybatisplus.extension.plugins.MybatisPlusInterceptor.intercept(MybatisPlusInterceptor.java:80) ~[mybatis-plus-extension-3.5.5.jar:3.5.5] at org.apache.ibatis.plugin.Plugin.invoke(Plugin.java:59) ~[mybatis-3.5.15.jar:3.5.15] at jdk.proxy2/jdk.proxy2.$Proxy106.query(Unknown Source) ~[na:na] at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:154) ~[mybatis-3.5.15.jar:3.5.15] at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:147) ~[mybatis-3.5.15.jar:3.5.15] at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:142) ~[mybatis-3.5.15.jar:3.5.15] at java.base/jdk.internal.reflect.DirectMethodHandleAccessor.invoke(DirectMethodHandleAccessor.java:103) ~[na:na] at java.base/java.lang.reflect.Method.invoke(Method.java:580) ~[na:na] at org.mybatis.spring.SqlSessionTemplate$SqlSessionInterceptor.invoke(SqlSessionTemplate.java:425) ~[mybatis-spring-3.0.3.jar:3.0.3] at jdk.proxy2/jdk.proxy2.$Proxy85.selectList(Unknown Source) ~[na:na] at org.mybatis.spring.SqlSessionTemplate.selectList(SqlSessionTemplate.java:224) ~[mybatis-spring-3.0.3.jar:3.0.3] at com.baomidou.mybatisplus.core.override.MybatisMapperMethod.executeForMany(MybatisMapperMethod.java:164) ~[mybatis-plus-core-3.5.5.jar:3.5.5] at com.baomidou.mybatisplus.core.override.MybatisMapperMethod.execute(MybatisMapperMethod.java:77) ~[mybatis-plus-core-3.5.5.jar:3.5.5] at com.baomidou.mybatisplus.core.override.MybatisMapperProxy$PlainMethodInvoker.invoke(MybatisMapperProxy.java:152) ~[mybatis-plus-core-3.5.5.jar:3.5.5] at com.baomidou.mybatisplus.core.override.MybatisMapperProxy.invoke(MybatisMapperProxy.java:89) ~[mybatis-plus-core-3.5.5.jar:3.5.5] at jdk.proxy2/jdk.proxy2.$Proxy86.pageWithRolesId(Unknown Source) ~[na:na] at com.easyauth.service.impl.EmployeeServiceImpl.conditionSearchWithRoleId(EmployeeServiceImpl.java:154) ~[classes/:na] at java.base/jdk.internal.reflect.DirectMethodHandleAccessor.invoke(DirectMethodHandleAccessor.java:103) ~[na:na] at java.base/java.lang.reflect.Method.invoke(Method.java:580) ~[na:na] at org.springframework.aop.support.AopUtils.invokeJoinpointUsingReflection(AopUtils.java:351) ~[spring-aop-6.1.4.jar:6.1.4] at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:713) ~[spring-aop-6.1.4.jar:6.1.4] at com.easyauth.service.impl.EmployeeServiceImpl$$SpringCGLIB$$0.conditionSearchWithRoleId() ~[classes/:na] at com.easyauth.controller.admin.EmployeeController.conditionSearch(EmployeeController.java:56) ~[classes/:na] at java.base/jdk.internal.reflect.DirectMethodHandleAccessor.invoke(DirectMethodHandleAccessor.java:103) ~[na:na] at java.base/java.lang.reflect.Method.invoke(Method.java:580) ~[na:na] at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:259) ~[spring-web-6.1.4.jar:6.1.4] at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:192) ~[spring-web-6.1.4.jar:6.1.4] at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:118) ~[spring-webmvc-6.1.4.jar:6.1.4] at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:920) ~[spring-webmvc-6.1.4.jar:6.1.4] at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:830) ~[spring-webmvc-6.1.4.jar:6.1.4] at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:87) ~[spring-webmvc-6.1.4.jar:6.1.4] at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1089) ~[spring-webmvc-6.1.4.jar:6.1.4] at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:979) ~[spring-webmvc-6.1.4.jar:6.1.4] at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1014) ~[spring-webmvc-6.1.4.jar:6.1.4] at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:903) ~[spring-webmvc-6.1.4.jar:6.1.4] at jakarta.servlet.http.HttpServlet.service(HttpServlet.java:564) ~[tomcat-embed-core-10.1.19.jar:6.0] at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:885) ~[spring-webmvc-6.1.4.jar:6.1.4] at jakarta.servlet.http.HttpServlet.service(HttpServlet.java:658) ~[tomcat-embed-core-10.1.19.jar:6.0] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:205) ~[tomcat-embed-core-10.1.19.jar:10.1.19] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:149) ~[tomcat-embed-core-10.1.19.jar:10.1.19] at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:51) ~[tomcat-embed-websocket-10.1.19.jar:10.1.19] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:174) ~[tomcat-embed-core-10.1.19.jar:10.1.19] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:149) ~[tomcat-embed-core-10.1.19.jar:10.1.19] at org.springframework.web.filter.CompositeFilter$VirtualFilterChain.doFilter(CompositeFilter.java:108) ~[spring-web-6.1.4.jar:6.1.4] at org.springframework.security.web.FilterChainProxy.lambda$doFilterInternal$3(FilterChainProxy.java:231) ~[spring-security-web-6.2.2.jar:6.2.2] at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:365) ~[spring-security-web-6.2.2.jar:6.2.2] at org.springframework.security.web.access.intercept.AuthorizationFilter.doFilter(AuthorizationFilter.java:100) ~[spring-security-web-6.2.2.jar:6.2.2] at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:374) ~[spring-security-web-6.2.2.jar:6.2.2] at org.springframework.security.web.access.ExceptionTranslationFilter.doFilter(ExceptionTranslationFilter.java:126) ~[spring-security-web-6.2.2.jar:6.2.2] at org.springframework.security.web.access.ExceptionTranslationFilter.doFilter(ExceptionTranslationFilter.java:120) ~[spring-security-web-6.2.2.jar:6.2.2] at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:374) ~[spring-security-web-6.2.2.jar:6.2.2] at org.springframework.security.web.session.SessionManagementFilter.doFilter(SessionManagementFilter.java:131) ~[spring-security-web-6.2.2.jar:6.2.2] at org.springframework.security.web.session.SessionManagementFilter.doFilter(SessionManagementFilter.java:85) ~[spring-security-web-6.2.2.jar:6.2.2] at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:374) ~[spring-security-web-6.2.2.jar:6.2.2] at org.springframework.security.web.authentication.AnonymousAuthenticationFilter.doFilter(AnonymousAuthenticationFilter.java:100) ~[spring-security-web-6.2.2.jar:6.2.2] at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:374) ~[spring-security-web-6.2.2.jar:6.2.2] at org.springframework.security.web.servletapi.SecurityContextHolderAwareRequestFilter.doFilter(SecurityContextHolderAwareRequestFilter.java:179) ~[spring-security-web-6.2.2.jar:6.2.2] at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:374) ~[spring-security-web-6.2.2.jar:6.2.2] at org.springframework.security.web.savedrequest.RequestCacheAwareFilter.doFilter(RequestCacheAwareFilter.java:63) ~[spring-security-web-6.2.2.jar:6.2.2] at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:374) ~[spring-security-web-6.2.2.jar:6.2.2] at org.springframework.security.web.authentication.logout.LogoutFilter.doFilter(LogoutFilter.java:107) ~[spring-security-web-6.2.2.jar:6.2.2] at org.springframework.security.web.authentication.logout.LogoutFilter.doFilter(LogoutFilter.java:93) ~[spring-security-web-6.2.2.jar:6.2.2] at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:374) ~[spring-security-web-6.2.2.jar:6.2.2] at org.springframework.web.filter.CorsFilter.doFilterInternal(CorsFilter.java:91) ~[spring-web-6.1.4.jar:6.1.4] at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:116) ~[spring-web-6.1.4.jar:6.1.4] at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:374) ~[spring-security-web-6.2.2.jar:6.2.2] at org.springframework.security.web.header.HeaderWriterFilter.doHeadersAfter(HeaderWriterFilter.java:90) ~[spring-security-web-6.2.2.jar:6.2.2] at org.springframework.security.web.header.HeaderWriterFilter.doFilterInternal(HeaderWriterFilter.java:75) ~[spring-security-web-6.2.2.jar:6.2.2] at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:116) ~[spring-web-6.1.4.jar:6.1.4] at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:374) ~[spring-security-web-6.2.2.jar:6.2.2] at org.springframework.security.web.context.SecurityContextHolderFilter.doFilter(SecurityContextHolderFilter.java:82) ~[spring-security-web-6.2.2.jar:6.2.2] at org.springframework.security.web.context.SecurityContextHolderFilter.doFilter(SecurityContextHolderFilter.java:69) ~[spring-security-web-6.2.2.jar:6.2.2] at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:374) ~[spring-security-web-6.2.2.jar:6.2.2] at org.springframework.security.web.context.request.async.WebAsyncManagerIntegrationFilter.doFilterInternal(WebAsyncManagerIntegrationFilter.java:62) ~[spring-security-web-6.2.2.jar:6.2.2] at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:116) ~[spring-web-6.1.4.jar:6.1.4] at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:374) ~[spring-security-web-6.2.2.jar:6.2.2] at org.springframework.security.web.session.DisableEncodeUrlFilter.doFilterInternal(DisableEncodeUrlFilter.java:42) ~[spring-security-web-6.2.2.jar:6.2.2] at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:116) ~[spring-web-6.1.4.jar:6.1.4] at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:374) ~[spring-security-web-6.2.2.jar:6.2.2] at org.springframework.security.web.FilterChainProxy.doFilterInternal(FilterChainProxy.java:233) ~[spring-security-web-6.2.2.jar:6.2.2] at org.springframework.security.web.FilterChainProxy.doFilter(FilterChainProxy.java:191) ~[spring-security-web-6.2.2.jar:6.2.2] at org.springframework.web.filter.CompositeFilter$VirtualFilterChain.doFilter(CompositeFilter.java:113) ~[spring-web-6.1.4.jar:6.1.4] at org.springframework.web.servlet.handler.HandlerMappingIntrospector.lambda$createCacheFilter$3(HandlerMappingIntrospector.java:195) ~[spring-webmvc-6.1.4.jar:6.1.4] at org.springframework.web.filter.CompositeFilter$VirtualFilterChain.doFilter(CompositeFilter.java:113) ~[spring-web-6.1.4.jar:6.1.4] at org.springframework.web.filter.CompositeFilter.doFilter(CompositeFilter.java:74) ~[spring-web-6.1.4.jar:6.1.4] at org.springframework.security.config.annotation.web.configuration.WebMvcSecurityConfiguration$CompositeFilterChainProxy.doFilter(WebMvcSecurityConfiguration.java:230) ~[spring-security-config-6.2.2.jar:6.2.2] at org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate(DelegatingFilterProxy.java:352) ~[spring-web-6.1.4.jar:6.1.4] at org.springframework.web.filter.DelegatingFilterProxy.doFilter(DelegatingFilterProxy.java:268) ~[spring-web-6.1.4.jar:6.1.4] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:174) ~[tomcat-embed-core-10.1.19.jar:10.1.19] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:149) ~[tomcat-embed-core-10.1.19.jar:10.1.19] at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:100) ~[spring-web-6.1.4.jar:6.1.4] at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:116) ~[spring-web-6.1.4.jar:6.1.4] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:174) ~[tomcat-embed-core-10.1.19.jar:10.1.19] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:149) ~[tomcat-embed-core-10.1.19.jar:10.1.19] at org.springframework.web.filter.FormContentFilter.doFilterInternal(FormContentFilter.java:93) ~[spring-web-6.1.4.jar:6.1.4] at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:116) ~[spring-web-6.1.4.jar:6.1.4] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:174) ~[tomcat-embed-core-10.1.19.jar:10.1.19] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:149) ~[tomcat-embed-core-10.1.19.jar:10.1.19] at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:201) ~[spring-web-6.1.4.jar:6.1.4] at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:116) ~[spring-web-6.1.4.jar:6.1.4] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:174) ~[tomcat-embed-core-10.1.19.jar:10.1.19] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:149) ~[tomcat-embed-core-10.1.19.jar:10.1.19] at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:167) ~[tomcat-embed-core-10.1.19.jar:10.1.19] at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:90) ~[tomcat-embed-core-10.1.19.jar:10.1.19] at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:482) ~[tomcat-embed-core-10.1.19.jar:10.1.19] at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:115) ~[tomcat-embed-core-10.1.19.jar:10.1.19] at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:93) ~[tomcat-embed-core-10.1.19.jar:10.1.19] at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:74) ~[tomcat-embed-core-10.1.19.jar:10.1.19] at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:344) ~[tomcat-embed-core-10.1.19.jar:10.1.19] at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:391) ~[tomcat-embed-core-10.1.19.jar:10.1.19] at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:63) ~[tomcat-embed-core-10.1.19.jar:10.1.19] at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:896) ~[tomcat-embed-core-10.1.19.jar:10.1.19] at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1744) ~[tomcat-embed-core-10.1.19.jar:10.1.19] at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:52) ~[tomcat-embed-core-10.1.19.jar:10.1.19] at org.apache.tomcat.util.threads.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1191) ~[tomcat-embed-core-10.1.19.jar:10.1.19] at org.apache.tomcat.util.threads.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:659) ~[tomcat-embed-core-10.1.19.jar:10.1.19] at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:63) ~[tomcat-embed-core-10.1.19.jar:10.1.19] at java.base/java.lang.Thread.run(Thread.java:1583) ~[na:na]

It looks like the set is empty. But I can't find it.

Answer 1

The problem is in the mapper's xml file.For incoming parameters：@Param("dto") EmployeePageQueryDTO queryDTO,it's illegal to use #{dto.roleIds.size()} directly.