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该问题已被官方收录

spring rmi空针

1

springRMI

class="cursor-pointer"> 详细描述

class="cursor-pointer"> 源码

Exception in thread "main" java.lang.NullPointerException
	at com.student.service.StudentServiceIpl.selectByPrimaryKey(StudentServiceIpl.java:39)
	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:498)
	at org.springframework.aop.support.AopUtils.invokeJoinpointUsingReflection(AopUtils.java:317)
	at org.springframework.aop.framework.ReflectiveMethodInvocation.invokeJoinpoint(ReflectiveMethodInvocation.java:190)
	at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:157)
	at org.springframework.remoting.support.RemoteInvocationTraceInterceptor.invoke(RemoteInvocationTraceInterceptor.java:78)
	at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
	at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:207)
	at com.sun.proxy.$Proxy1.selectByPrimaryKey(Unknown Source)
	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:498)
	at org.springframework.remoting.support.RemoteInvocation.invoke(RemoteInvocation.java:212)
	at org.springframework.remoting.support.DefaultRemoteInvocationExecutor.invoke(DefaultRemoteInvocationExecutor.java:39)
	at org.springframework.remoting.support.RemoteInvocationBasedExporter.invoke(RemoteInvocationBasedExporter.java:78)
	at org.springframework.remoting.rmi.RmiBasedExporter.invoke(RmiBasedExporter.java:73)
	at org.springframework.remoting.rmi.RmiInvocationWrapper.invoke(RmiInvocationWrapper.java:74)
	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:498)
	at sun.rmi.server.UnicastServerRef.dispatch(UnicastServerRef.java:361)
	at sun.rmi.transport.Transport$1.run(Transport.java:200)
	at sun.rmi.transport.Transport$1.run(Transport.java:197)
	at java.security.AccessController.doPrivileged(Native Method)
	at sun.rmi.transport.Transport.serviceCall(Transport.java:196)
	at sun.rmi.transport.tcp.TCPTransport.handleMessages(TCPTransport.java:568)
	at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.run0(TCPTransport.java:826)
	at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.lambda$run$0(TCPTransport.java:683)
	at java.security.AccessController.doPrivileged(Native Method)
	at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.run(TCPTransport.java:682)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
	at java.lang.Thread.run(Thread.java:748)
	at org.springframework.remoting.support.RemoteInvocationUtils.fillInClientStackTraceIfPossible(RemoteInvocationUtils.java:45)
	at org.springframework.remoting.rmi.RmiClientInterceptor.doInvoke(RmiClientInterceptor.java:353)
	at org.springframework.remoting.rmi.RmiClientInterceptor.invoke(RmiClientInterceptor.java:260)
	at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
	at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:207)
	at com.sun.proxy.$Proxy8.selectByPrimaryKey(Unknown Source)
	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:498)
	at org.springframework.aop.support.AopUtils.invokeJoinpointUsingReflection(AopUtils.java:317)
	at org.springframework.aop.framework.ReflectiveMethodInvocation.invokeJoinpoint(ReflectiveMethodInvocation.java:190)
	at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:157)
	at org.springframework.aop.framework.adapter.MethodBeforeAdviceInterceptor.invoke(MethodBeforeAdviceInterceptor.java:52)
	at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
	at org.springframework.aop.aspectj.AspectJAfterAdvice.invoke(AspectJAfterAdvice.java:43)
	at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
	at org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(ExposeInvocationInterceptor.java:92)
	at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
	at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:207)
	at com.sun.proxy.$Proxy20.selectByPrimaryKey(Unknown Source)
	at com.student.rmi.main.main(main.java:11)

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lniux命令报错

1

linux命令

class="cursor-pointer"> 详细描述

class="cursor-pointer"> 错误截图

该问题已被官方收录

日历签到的问题

0

1

复盘踩坑

class="cursor-pointer"> 详细描述

class="cursor-pointer"> 错误截图

class="cursor-pointer"> 源码

@RequestMapping(value = "/a/sign/{userId}",method = RequestMethod.GET)
	public String getUserSign(HttpServletRequest request,
							  HttpServletResponse response, ModelMap model, @PathVariable Long userId, Integer year, Integer month)
			throws Exception {
		if (userId == null || year == null || month == null){
			model.addAttribute("code",-200000);
			model.addAttribute("specialmessage", "参数缺失");
			return "common/json";
		}
		try{
			Map<String,Object> time = TimeUtils.getStartAndEnd(year,month,null);
			Map<String,Object> parmas = SqlUtils.getSignList(userId,(Long)time.get("start"),(Long)time.get("end"));
			List<Long> ids = userSignService.getIdsByDynamicCondition(UserSign.class,parmas,0,Integer.MAX_VALUE);
			List<UserSign> userSignList = userSignService.getObjectsByIds(ids);
			log.info("签到表++++++++++++++++++++++++++++++++++++++++++"+userSignList);
			if (userSignList.isEmpty()){
				model.addAttribute("code", -2005);
				model.addAttribute("signList",null);
			}
			else {
				model.addAttribute("signList", userSignList);
				model.addAttribute("code", 0);
			}
			User user = userService.getObjectById(userId);
			if (user == null ){
				model.addAttribute("code", -5002);
				return "/common/json";
			}
			Long total = user.getTotal();
			model.addAttribute("dayCounts", total);
		}
		catch (Throwable t) {
			t.printStackTrace();
			log.error(t.getMessage());
			log.error("get sign error,userId is  " + userId);
			model.addAttribute("code", -2099);
		}
		return "userSign/json/userSignListJson";
	}

该问题已被官方收录

（filter status:REJECTED）发布到服务器提示过滤状态拒绝

2

1

tuscany

class="cursor-pointer"> 详细描述

class="cursor-pointer"> 错误截图

该问题已被官方收录

用拦截器的时候使用request转发页面，如何能够跳转到tiles配置的页面？

2

1

interceptor

class="cursor-pointer"> 详细描述

class="cursor-pointer"> 错误截图

该问题已被官方收录

ssm框架乱码

2

1

SSM

class="cursor-pointer"> 详细描述

class="cursor-pointer"> 错误截图

class="cursor-pointer"> 源码

<%@ page language="java" contentType="text/html; charset=UTF-8"
         pageEncoding="UTF-8" import="java.util.*" isELIgnored="false" %>

<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>
<%@ taglib prefix ="json" uri ="http://www.atg.com/taglibs/json"%>

<script src="http://libs.baidu.com/jquery/2.0.0/jquery.min.js"></script>
<script type="text/javascript">
    /*将post method 改变为delete*/
    $(function(){
        $(".delete").click(function(){
            var href=$(this).attr("href");
            $("#formdelete").attr("action",href).submit();
            return false;
        })
    })
</script>
<form id="formdelete" action="" method="POST" >
    <input type="hidden" name="_method" value="DELETE">
</form>
<div style="width:500px;margin:0px auto;text-align:center">
<json:object>
</json:object>
    <json:array name="students" var="student" items="${students}">
        <json:object>
            <json:property name="id" value="${student.id}"/>
            <json:property name="name" value="${student.name}"/>
            <json:property name="qq" value="${student.qq}"/>
            <json:property name="wish" value="${student.wish}"/>
            <json:property name="school" value="${student.school}"/>
            <json:property name="enrolment_time" value="${student.enrolmentTime}"/>
            <json:property name="type" value="${student.type}"/>
            <json:property name="know_from" value="${student.knowFrom}"/>
            <json:property name="create_at" value="${student.createAt}"/>
            <json:property name="update_at" value="${student.updateAt}"/>
        </json:object>
    </json:array>
<table align='center' border='1' cellspacing='0'>
    <tr>
        <td>id</td>
        <td>name</td>
        <td>qq</td>
        <td>wish</td>
        <td>school</td>
        <td>enrolment_time</td>
        <td>type</td>
        <td>know_from</td>
        <td>create_at</td>
        <td>update_at</td>
        <td>编辑</td>
        <td>删除</td>
    </tr>
    <c:forEach items="${students}" var="student">
        <tr>
            <td>${student.id}</td>
            <td>${student.name}</td>
            <td>${student.qq}</td>
            <td>${student.wish}</td>
            <td>${student.school}</td>
            <td>${student.enrolmentTime}</td>
            <td>${student.type}</td>
            <td>${student.knowFrom}</td>
            <td>${student.createAt}</td>
            <td>${student.updateAt}</td>
            <td><a href="/students/${student.id}">编辑</a></td>
            <td><a class="delete" href="/students/${student.id}">删除</a></td>
        </tr>
    </c:forEach>
</table>
<div style="text-align:center">
    <a href="?start=0">首  页</a>
    <a href="?start=${page.start-page.count}">上一页</a>
    <a href="?start=${page.start+page.count}">下一页</a>
    <a href="?start=${page.last}">末  页</a>
</div>
<div style="text-align:center;margin-top:40px">
    <form method="post" action="students">
        名字：    <input name="name" value="" type="text"> <br><br>
        qq:       <input name="qq" value="" type="text"> <br><br>
        入门誓言：<input name="wish" value="" type="text"> <br><br>
        毕业院校：<input name="school" value="" type="text"> <br><br>
        入学时间：<input name="enrolmentTime" value="" type="text"> <br><br>
        修真类型：<input name="type" value="" type="text"> <br><br>
        了解渠道：<input name="knowFrom" value="" type="text"> <br><br>
        创建时间：<input name="createAt" value="" type="text"> <br><br>
        更新时间：<input name="updateAt" value="" type="text"> <br><br>
             <input type="submit" value="增加分类">
    </form>
</div>
</div>

</script>

该问题已被官方收录

redis序列化问题

0

1

redis

class="cursor-pointer"> 详细描述

class="cursor-pointer"> 错误截图

class="cursor-pointer"> 源码

  @Override
    //单条查询
    public User findUserById(int userId) {
        ValueOperations<String, Object> vos = redisTemplate.opsForValue();

        User user = null;
        if ("".equals(vos.get(String.valueOf(userId)))){

//            (redisTemplate.opsForValue().get(String.valueOf(userId))==null)
            logger.info("\n从缓存返回空值");
            return user;
        }

        try {

            if (vos.get(String.valueOf(userId)) != null) {
                logger.info("\n" + "从缓存中查询单条数据");
                user = (User) vos.get(String.valueOf(userId));
            } else {
                logger.info("\n" + "从数据库中查询单条数据");
                user = userDao.findUserById(userId);
                if (user != null) {
                    vos.set(String.valueOf(userId), user);
                    logger.info("\n" + "新增单条缓存数据:" + vos.get(String.valueOf(userId)));
                } else {
                    vos.set(String.valueOf(userId),"", 60,TimeUnit.SECONDS);
                    logger.info("\n" + "将空值存到缓存");
                }
            }
        } catch (Throwable t) {
            t.printStackTrace();
        }
        return user;


    }

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用./shutdown.sh关闭rmi服务器的tomcat,然后启动客户端的错误

0

1

springRMI

class="cursor-pointer"> 详细描述

class="cursor-pointer"> 错误截图

java.rmi.ConnectException: Connection refused to host:127.0.0.1; nested exception is:
        java.net.ConnectException: Connection refused: connect
        at sun.rmi.transport.tcp.TCPEndpoint.newSocket(Unknown Source)
        at sun.rmi.transport.tcp.TCPChannel.createConnection(Unknown Source)
        at sun.rmi.transport.tcp.TCPChannel.newConnection(Unknown Source)
        at sun.rmi.server.UnicastRef.invoke(Unknown Source)
        at java.rmi.server.RemoteObjectInvocationHandler.invokeRemoteMethod
        (Unknown Source)
        at java.rmi.server.RemoteObjectInvocationHandler.invoke(Unknown Source)
        at $Proxy0.call(Unknown Source)
        at RMI.Client.callRMI(Client.java:39)
        at RMI.Client.main(Client.java:53)
        Caused by: java.net.ConnectException: Connection refused: connect
        at java.net.PlainSocketImpl.socketConnect(Native Method)
        at java.net.PlainSocketImpl.doConnect(Unknown Source)
        at java.net.PlainSocketImpl.connectToAddress(Unknown Source)
        at java.net.PlainSocketImpl.connect(Unknown Source)
        at java.net.SocksSocketImpl.connect(Unknown Source)
        at java.net.Socket.connect(Unknown Source)
        at java.net.Socket.connect(Unknown Source)
        at java.net.Socket.<init>(Unknown Source)
        at java.net.Socket.<init>(Unknown Source)
        at sun.rmi.transport.proxy.RMIDirectSocketFactory.createSocket
        (Unknown Source)
        at sun.rmi.transport.proxy.RMIMasterSocketFactory.createSocket
        (Unknown Source)
        ... 9 more

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maven里jar包该在怎么用，POM.XML的作用是什么

1

maven

class="cursor-pointer"> 详细描述

class="cursor-pointer"> 错误截图

该问题已被官方收录

shiro如何整合JWT

0

1

shiro

class="cursor-pointer"> 详细描述

class="cursor-pointer"> 错误截图