java ssm 登录验证失败提示问题 5C

ssm框架在验证登录的时候,成功进行页面的跳转,失败不跳转页面,但是在原登录页面进行提示(可以弹出,也可以加一个html元素)。登录用的是form表单,没用ajax。这个应该怎么做?

9个回答

ssm是后端框架,只要负责后端处理,你只要处理是否登陆成功就好了,登陆成功则返回给前端登陆成功的信息,前端实现跳转;登陆失败,则前端不跳转。

controller中
失败时 把失败提示放到request或者session中
request.setAttribute("Msg", "用户名或密码错误!");
页面上弄个span标签${Msg} 接收不就好了

qq_26856465
qq_26856465 回复qq_36375934: 返回时需要配置视图解析器
一年多之前 回复
qq_36375934
qq_charm 我是这样想的,但是我的登录页面时在webapp下的,然后返回用的是modelandview,在写返回路径的时候总是不对
一年多之前 回复

既然使用的form表单提交那就一定会发生页面的跳转,即使是登录页本身也会刷新。

请你把你的登录部分代码贴出来才好给你看登录失败怎么处理。
或者你参考ajax提交,在提交失败的回调中去弹出一个登录失败的提示。

失败时还返回登录界面,把用户名 和错误消息返回。界面显示用户名和消息就行了啊 错误消息第一次进入登录界面时做非空不显示处理就行了

失败时还返回登录界面,把用户名 和错误消息返回。界面显示用户名和消息就行了啊

你可以看一下form表达如何让iframe代替发送请求

确实,你既然用了form提交,那么你一定会返回一个界面,哪怕是原登录界面,你这中间也是发生了跳转的。这时候你可以在登录提交的controller里写一个提示request.setAttribute("error", "用户名或密码错误!");然后就在前台判断这个值是不是空就行了

改成ajax提交form是最好的,用其他的方法来实现都会造成或多或少的困扰。

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报错如下: ``` HTTP Status 500 – Internal Server Error Type Exception Report Message Servlet.init() for servlet SpringMVC threw exception Description The server encountered an unexpected condition that prevented it from fulfilling the request. Exception javax.servlet.ServletException: Servlet.init() for servlet SpringMVC threw exception org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:478) org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:80) org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:341) org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:783) org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66) org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:798) org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1441) org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49) java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) java.lang.Thread.run(Thread.java:745) Root Cause org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'org.springframework.context.annotation.internalAsyncAnnotationProcessor': Initialization of bean failed; nested exception is java.lang.NoSuchMethodError: org.springframework.aop.interceptor.AsyncExecutionInterceptor.<init>(Ljava/util/concurrent/Executor;Lorg/springframework/aop/interceptor/AsyncUncaughtExceptionHandler;)V org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:547) org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:476) org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:303) org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230) org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:299) org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:199) org.springframework.context.support.PostProcessorRegistrationDelegate.registerBeanPostProcessors(PostProcessorRegistrationDelegate.java:220) org.springframework.context.support.AbstractApplicationContext.registerBeanPostProcessors(AbstractApplicationContext.java:615) org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:465) org.springframework.web.servlet.FrameworkServlet.configureAndRefreshWebApplicationContext(FrameworkServlet.java:663) org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:629) org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:677) org.springframework.web.servlet.FrameworkServlet.initWebApplicationContext(FrameworkServlet.java:548) org.springframework.web.servlet.FrameworkServlet.initServletBean(FrameworkServlet.java:489) org.springframework.web.servlet.HttpServletBean.init(HttpServletBean.java:136) javax.servlet.GenericServlet.init(GenericServlet.java:158) org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:478) org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:80) org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:341) org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:783) org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66) org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:798) org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1441) org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49) java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) java.lang.Thread.run(Thread.java:745) Root Cause java.lang.NoSuchMethodError: org.springframework.aop.interceptor.AsyncExecutionInterceptor.<init>(Ljava/util/concurrent/Executor;Lorg/springframework/aop/interceptor/AsyncUncaughtExceptionHandler;)V org.springframework.scheduling.annotation.AnnotationAsyncExecutionInterceptor.<init>(AnnotationAsyncExecutionInterceptor.java:60) org.springframework.scheduling.annotation.AsyncAnnotationAdvisor.buildAdvice(AsyncAnnotationAdvisor.java:150) org.springframework.scheduling.annotation.AsyncAnnotationAdvisor.<init>(AsyncAnnotationAdvisor.java:99) org.springframework.scheduling.annotation.AsyncAnnotationBeanPostProcessor.setBeanFactory(AsyncAnnotationBeanPostProcessor.java:105) org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeAwareMethods(AbstractAutowireCapableBeanFactory.java:1585) org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1553) org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:539) org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:476) org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:303) org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230) org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:299) org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:199) org.springframework.context.support.PostProcessorRegistrationDelegate.registerBeanPostProcessors(PostProcessorRegistrationDelegate.java:220) org.springframework.context.support.AbstractApplicationContext.registerBeanPostProcessors(AbstractApplicationContext.java:615) org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:465) org.springframework.web.servlet.FrameworkServlet.configureAndRefreshWebApplicationContext(FrameworkServlet.java:663) org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:629) org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:677) org.springframework.web.servlet.FrameworkServlet.initWebApplicationContext(FrameworkServlet.java:548) org.springframework.web.servlet.FrameworkServlet.initServletBean(FrameworkServlet.java:489) org.springframework.web.servlet.HttpServletBean.init(HttpServletBean.java:136) javax.servlet.GenericServlet.init(GenericServlet.java:158) org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:478) org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:80) org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:341) org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:783) org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66) org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:798) org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1441) org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49) java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) java.lang.Thread.run(Thread.java:745) Note The full stack trace of the root cause is available in the server logs. Apache Tomcat/8.5.12 ``` 一搭到服务器上就出现这个错误,但是本地window没问题;卡了一天了,脑瓜子呼呼的,第一次用这个玩意,实在看不出来啥问题了,有没有大佬帮忙指点指点,给条明路呀!! 下面是几个基础配置: web.xml: ``` <?xml version="1.0" encoding="UTF-8"?> <web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd" version="3.0"> <display-name>Archetype Created Web Application</display-name> <context-param> <param-name>contextConfigLocation</param-name> <param-value>classpath:spring-mybatis.xml</param-value> </context-param> <filter> <filter-name>encodingFilter</filter-name> <filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class> <async-supported>true</async-supported> <init-param> <param-name>encoding</param-name> <param-value>UTF-8</param-value> </init-param> </filter> <filter-mapping> <filter-name>encodingFilter</filter-name> <url-pattern>/*</url-pattern> </filter-mapping> <filter> <filter-name>CORSFilter</filter-name> <filter-class>com.bls.mp.common.MyFilter</filter-class> <init-param> <param-name>excludedPages</param-name> <param-value>/UserAuthServlet</param-value> </init-param> </filter> <filter-mapping> <filter-name>CORSFilter</filter-name> <url-pattern>/*</url-pattern> </filter-mapping> <listener> <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class> </listener> <listener> <listener-class>org.springframework.web.util.IntrospectorCleanupListener</listener-class> </listener> <servlet> <servlet-name>SpringMVC</servlet-name> <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class> <init-param> <param-name>contextConfigLocation</param-name> <param-value>classpath:spring-mvc.xml</param-value> </init-param> <load-on-startup>1</load-on-startup> <async-supported>true</async-supported> </servlet> <servlet-mapping> <servlet-name>SpringMVC</servlet-name> <url-pattern>/</url-pattern> </servlet-mapping> <welcome-file-list> <welcome-file>/index.jsp</welcome-file> </welcome-file-list> </web-app> ``` spring-mvc.xml: ``` <?xml version="1.0" encoding="UTF-8"?> <beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:p="http://www.springframework.org/schema/p" xmlns:context="http://www.springframework.org/schema/context" xmlns:mvc="http://www.springframework.org/schema/mvc" xmlns:task="http://www.springframework.org/schema/task" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-4.0.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.0.xsd http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-4.0.xsd http://www.springframework.org/schema/task http://www.springframework.org/schema/task/spring-task-4.0.xsd" > <!-- 自动扫描该包,使SpringMVC认为包下用了@controller注解的类是控制器 --> <context:component-scan base-package="com.bls.mp.controller"/> <!--避免IE执行AJAX时,返回JSON出现下载文件 --> <bean id="mappingJacksonHttpMessageConverter" class="org.springframework.http.converter.json.MappingJacksonHttpMessageConverter"> <property name="supportedMediaTypes"> <list> <value>text/html;charset=UTF-8</value> </list> </property> </bean> <!-- <bean id="thirdDataService" class="com.bls.mp.service.impl.ThirdDataServiceImpl"/>--> <bean class="com.bls.mp.common.SpringTool"/> <!-- 启动SpringMVC的注解功能,完成请求和注解POJO的映射 --> <!-- <bean class="org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter"> <property name="messageConverters"> <list> <ref bean="mappingJacksonHttpMessageConverter" /> JSON转换器 </list> </property> </bean>--> <!-- 定义跳转的文件的前后缀 ,视图模式配置--> <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver"> <!-- 这里的配置我的理解是自动给后面action的方法return的字符串加上前缀和后缀,变成一个 可用的url地址 --> <property name="prefix" value="/WEB-INF/resources/jsp/" /> <property name="suffix" value=".jsp" /> <property name="viewClass" value="org.springframework.web.servlet.view.JstlView"></property> </bean> <!-- 配置文件上传,如果没有使用文件上传可以不用配置,当然如果不配,那么配置文件中也不必引入上传组件包 --> <bean id="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver"> <!-- 默认编码 --> <property name="defaultEncoding" value="utf-8" /> <!-- 文件大小最大值 --> <property name="maxUploadSize" value="10485760000" /> <!-- 内存中的最大值 --> <property name="maxInMemorySize" value="40960" /> </bean> <!-- 全局异常处理器 --> <bean class="com.bls.mp.common.exception.CustomExceptionResolver"></bean> <mvc:annotation-driven/> <!-- 拦截器配置 --> <mvc:interceptors> <mvc:interceptor> <mvc:mapping path="/setadmin"/> <!--<mvc:mapping path="/user/userList"/> --> <mvc:mapping path="/Blocker"/> <mvc:mapping path="/goods/goods"/> <bean class="com.bls.mp.interceptor.AuthInterceptor"></bean> </mvc:interceptor> </mvc:interceptors> <task:annotation-driven/> <!-- 配置访问静态文件 --> <mvc:default-servlet-handler/> <mvc:resources location="/images/" mapping="/images/**"/> <mvc:resources location="/WEB-INF/js/" mapping="/js/**"/> <mvc:resources location="/WEB-INF/resources/jsp/" mapping="/jsp/**"/> <mvc:resources location="/WEB-INF/resources/css/" mapping="/css/**"/> </beans> ``` spring-mybatis.xml: ``` <?xml version="1.0" encoding="UTF-8"?> <beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:p="http://www.springframework.org/schema/p" xmlns:context="http://www.springframework.org/schema/context" xmlns:mvc="http://www.springframework.org/schema/mvc" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-4.0.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.0.xsd http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-4.0.xsd"> <!-- 自动扫描 --> <context:component-scan base-package="com.bls.mp"/> <!-- 引入配置文件 --> <bean id="propertyConfigurer" class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer"> <property name="location" value="classpath:jdbc.properties" /> </bean> <bean id="dataSource" class="org.apache.commons.dbcp.BasicDataSource" destroy-method="close"> <property name="driverClassName" value="${jdbc.driver}" /> <property name="url" value="${jdbc.url}" /> <property name="username" value="${jdbc.username}" /> <property name="password" value="${jdbc.password}" /> <!-- 初始化连接大小 --> <property name="initialSize" value="${initialSize}"></property> <!-- 连接池最大数量 --> <property name="maxActive" value="${maxActive}"></property> <!-- 连接池最大空闲 --> <property name="maxIdle" value="${maxIdle}"></property> <!-- 连接池最小空闲 --> <property name="minIdle" value="${minIdle}"></property> <!-- 获取连接最大等待时间 --> <property name="maxWait" value="${maxWait}"></property> </bean> <!-- spring和MyBatis完美整合,不需要mybatis的配置映射文件 --> <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean"> <property name="dataSource" ref="dataSource" /> <!-- 自动扫描mapping.xml文件 --> <property name="mapperLocations" value="classpath:com/bls/mp/mapping/*.xml"></property> </bean> <!-- DAO接口所在包名,Spring会自动查找其下的类 --> <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer"> <property name="basePackage" value="com.bls.mp.dao" /> <property name="sqlSessionFactoryBeanName" value="sqlSessionFactory"></property> </bean> <!-- (事务管理)transaction manager, use JtaTransactionManager for global tx --> <bean id="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager"> <property name="dataSource" ref="dataSource" /> </bean> </beans> ``` jdk版本: 1.8.0_222 tomcat 版本:8.0 有没有大佬来给看看呀0.0
java SSM整合问题,无法进入Controller
![图片说明](https://img-ask.csdn.net/upload/201805/10/1525933317_321633.png) web.xml ``` <context-param> <param-name>contextConfigLocation</param-name> <param-value>classpath:spring-mybatis.xml</param-value> </context-param> <servlet> <servlet-name>SpringMVC</servlet-name> <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class> <init-param> <param-name>contextConfigLocation</param-name> <param-value>classpath:spring-mvc.xml</param-value> </init-param> <load-on-startup>1</load-on-startup> <async-supported>true</async-supported> </servlet> <servlet-mapping> <servlet-name>SpringMVC</servlet-name> <!-- 此处可以可以配置成*.do,对应struts的后缀习惯 --> <url-pattern>/</url-pattern> </servlet-mapping> ``` spring-mvc.xml: ``` <beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:p="http://www.springframework.org/schema/p" xmlns:context="http://www.springframework.org/schema/context" xmlns:mvc="http://www.springframework.org/schema/mvc" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.1.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.1.xsd http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-4.0.xsd"> <!-- 自动扫描该包,使SpringMVC认为包下用了@controller注解的类是控制器 --> <context:component-scan base-package="com.controller.*" /> <!--避免IE执行AJAX时,返回JSON出现下载文件 --> <bean id="mappingJacksonHttpMessageConverter" class="org.springframework.http.converter.json.MappingJacksonHttpMessageConverter"> <property name="supportedMediaTypes"> <list> <value>text/html;charset=UTF-8</value> </list> </property> </bean> ``` Spring-mybatis.xml: ``` <!-- 自动扫描 --> <!-- <context:component-scan base-package="com.services.*" /> --> <!-- 引入配置文件 --> <bean id="propertyConfigurer" class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer"> <property name="location" value="classpath:jdbc.properties" /> </bean> <bean id="dataSource" class="org.apache.commons.dbcp.BasicDataSource" destroy-method="close"> <property name="driverClassName" value="${driver}" /> <property name="url" value="${url}" /> <property name="username" value="${username}" /> <property name="password" value="${password}" /> <!-- 初始化连接大小 --> <property name="initialSize" value="${initialSize}"></property> <!-- 连接池最大数量 --> <property name="maxActive" value="${maxActive}"></property> <!-- 连接池最大空闲 --> <property name="maxIdle" value="${maxIdle}"></property> <!-- 连接池最小空闲 --> <property name="minIdle" value="${minIdle}"></property> <!-- 获取连接最大等待时间 --> <property name="maxWait" value="${maxWait}"></property> </bean> <!-- 第一种 spring和MyBatis完美整合,不需要mybatis的配置映射文件 --> <!-- <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean"> <property name="dataSource" ref="dataSource" /> 自动扫描mapping.xml文件 <property name="mapperLocations" value="classpath*:mapping/*.xml"></property> </bean> --> <!--第二种 mybatis-spring整合 手动配置mybatis配置文件--> <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean"> <property name="dataSource" ref="dataSource"/> <property name="configLocation" value="classpath:mybatis-config.xml"/> </bean> <!-- DAO接口所在包名,Spring会自动查找其下的类 --> <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer"> <property name="basePackage" value="com.DAO" /> <property name="sqlSessionFactoryBeanName" value="sqlSessionFactory"></property> </bean> ``` mybatis.xml ``` <?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE configuration PUBLIC "-//mybatis.org//DTD Config 3.0//EN" "http://mybatis.org/dtd/mybatis-3-config.dtd"> <configuration> <!-- 创建实体类别名 --> <typeAliases> <!--type:对象类型 alias:对象别名 --> <typeAlias type="com.model.User" alias="User"/> </typeAliases> <!--配置mybatis映射文件 --> <mappers> <mapper resource="com/mapper/UserMapper.xml"/> </mappers> </configuration> ``` DAO: ``` package com.DAO; import com.model.User; public interface UserDao { User findUserByName(String username,String pwd); } ``` mapper: ``` <mapper namespace="com.DAO.UserDao"> <!-- 新增 --> <insert id="saveUser" parameterType="com.cn.ssm.pojo.User" > insert into t_user(user_name,user_age) values (#{username},#{age}) </insert> <!-- 修改 --> <update id="updateUser" parameterType="com.cn.ssm.pojo.User" > update t_user set user_name=#{username},user_age=#{age} where user_id=#{id} </update> <!-- 删除 --> <delete id="deleteUser" parameterType="int"> delete from t_user where user_id=#{id} </delete> <!-- 根据id查找单个用户 --> <select id="findUserById" parameterType="java.lang.Integer" resultType="com.cn.ssm.pojo.User"> select id,user_name,age from user_t where id=#{id} </select> <!-- 查询所有 --> <select id="findAll" resultType="com.cn.ssm.pojo.User"> select user_id id,user_name userName,user_age age from t_user </select> <!-- 根据用户名和密码查询用户 --> <select id="findUserByName" parameterType="String" resultType="com.model.User"> <!-- 只传一个参数到sql语句时,可以直接写参数名,当传多个参数时,需用0,1,2...,或者在dao层使用@Param注解--> select * from userinfo where UserName=#{0} AND PassWord=#{1} </select> ``` services: ``` package com.services; import com.model.User; public interface IUserService { public User findUserByName(String username,String pwd); } ``` services.implents: ``` @Service @Transactional public class UserServiceImpl implements IUserService{ @Autowired public UserDao UserMapper; public User findUserByName(String name,String password){ return this.UserMapper.findUserByName(name, password); } } ``` Controller: ``` @Controller @RequestMapping("/user") public class UserController { @Autowired private IUserService userService; @RequestMapping("longin") public void checkLogin(HttpServletRequest request,HttpServletResponse response){ String username=request.getParameter("name"); String password=request.getParameter("password"); response.setCharacterEncoding("utf-8"); System.out.println(username+","+password); User user=userService.findUserByName(username, password); HttpSession session=request.getSession(); if(user!=null){ session.setAttribute("user", user); try { //response.sendRedirect("../index2.jsp"); response.getWriter().write("登录失败"); } catch (IOException e) { e.printStackTrace(); } }else{ try { response.getWriter().write("登录失败"); } catch (IOException e) { // TODO Auto-generated catch block ``` jsp: ``` <body> <form action="user/longin"> <label>用户名:<input type="text" name="name"></label> <label>密码:<input type="password" name="password"></label> <input type="submit" value="登录..."> </form> <button onclick="login_ip()">IP登录</button> </body> ```
java,SSM项目能不能直接调用PC端自用的打印图片设置界面?
java,SSM项目能不能直接调用PC端自用的打印图片设置界面?
java ssm框架,开发web项目,在方法中代码执行顺序问题
具体问题如下图 : ![图片说明](https://img-ask.csdn.net/upload/201911/30/1575114708_513502.png) 各位大神,这种情况是怎么出来的,有什么解决办法ma?
java SSM框架 使用JSONP返回数据出现问题
用SSM框架返回jsonp数据,但是如果Controller 中 传递的参数包含 对象,在返回JSONP数据前段解析时会包含这个传进来的对象,这是不是配置问题?![图片说明](https://img-ask.csdn.net/upload/201609/20/1474358752_745005.png),![图片说明](https://img-ask.csdn.net/upload/201609/20/1474358763_102887.png)
JAVA SSM 实体类作为属性,查到的值为null
想要用一个实体类的作为另一个实体类的属性,把四张表的数据全都查出来,但是查出来为空。 ![图片说明](https://img-ask.csdn.net/upload/202001/03/1578012132_675446.png)![图片说明](https://img-ask.csdn.net/upload/202001/03/1578012143_238481.png)![图片说明](https://img-ask.csdn.net/upload/202001/03/1578012150_355888.png)![图片说明](https://img-ask.csdn.net/upload/202001/03/1578012157_470870.png)
JAVA SSM访问web-inf目录下jsp问题
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com.rn.service.impl.UserServiceImpl.doLogin(UserServiceImpl.java:57) at com.rn.service.impl.UserServiceImpl$$FastClassBySpringCGLIB$$30adad5a.invoke(<generated>) at org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:204) at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.invokeJoinpoint(CglibAopProxy.java:700) at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:150) at org.springframework.transaction.interceptor.TransactionInterceptor$1.proceedWithInvocation(TransactionInterceptor.java:96) at org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:260) at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:94) at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:172) at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:633) at com.rn.service.impl.UserServiceImpl$$EnhancerBySpringCGLIB$$90515f43.doLogin(<generated>) at com.rn.controller.ManagerController.loginback(ManagerController.java:48) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:606) at org.springframework.web.method.support.InvocableHandlerMethod.invoke(InvocableHandlerMethod.java:215) at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:132) at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:104) at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandleMethod(RequestMappingHandlerAdapter.java:743) at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:672) at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:82) at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:919) at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:851) at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:953) at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:844) at javax.servlet.http.HttpServlet.service(HttpServlet.java:617) at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:829) at javax.servlet.http.HttpServlet.service(HttpServlet.java:717) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) at org.apache.shiro.web.servlet.ProxiedFilterChain.doFilter(ProxiedFilterChain.java:61) at org.apache.shiro.web.servlet.AdviceFilter.executeChain(AdviceFilter.java:108) at org.apache.shiro.web.servlet.AdviceFilter.doFilterInternal(AdviceFilter.java:137) at org.apache.shiro.web.servlet.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:125) at org.apache.shiro.web.servlet.ProxiedFilterChain.doFilter(ProxiedFilterChain.java:66) at org.apache.shiro.web.servlet.AbstractShiroFilter.executeChain(AbstractShiroFilter.java:449) at org.apache.shiro.web.servlet.AbstractShiroFilter$1.call(AbstractShiroFilter.java:365) at org.apache.shiro.subject.support.SubjectCallable.doCall(SubjectCallable.java:90) at org.apache.shiro.subject.support.SubjectCallable.call(SubjectCallable.java:83) at org.apache.shiro.subject.support.DelegatingSubject.execute(DelegatingSubject.java:383) at org.apache.shiro.web.servlet.AbstractShiroFilter.doFilterInternal(AbstractShiroFilter.java:362) at org.apache.shiro.web.servlet.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:125) at org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate(DelegatingFilterProxy.java:343) at org.springframework.web.filter.DelegatingFilterProxy.doFilter(DelegatingFilterProxy.java:260) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:88) at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:106) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233) at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:128) at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102) at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109) at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:286) at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:845) at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:583) at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:447) at java.lang.Thread.run(Thread.java:745) ``` ``` UserRealm.java public class UserRealm extends AuthorizingRealm { @Autowired private UserService userSer; /** 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