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测试客户端端口错误

1

公司框架使用

class="cursor-pointer"> 详细描述

class="cursor-pointer"> 错误截图

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测试运行出错

1

class="cursor-pointer"> 详细描述

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找不到指定的studentMapper类

0

1

mybatis

class="cursor-pointer"> 详细描述

class="cursor-pointer"> 错误截图

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Tomcat运行war包时出错

4

1

jetty/tomcat

class="cursor-pointer"> 详细描述

class="cursor-pointer"> 错误截图

class="cursor-pointer"> 源码

HTTP Status 404 – Not Found

Type Status Report

Message /students/jump3

Description The origin server did not find a current representation for the target resource or is not willing to disclose that one exists.

Apache Tomcat/8.5.34

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无法调用另一个类

1

class="cursor-pointer"> 详细描述

class="cursor-pointer"> 错误截图

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redistemplate 不能自增得到值

0

1

class="cursor-pointer"> 详细描述

class="cursor-pointer"> 错误截图

class="cursor-pointer"> 源码

Caused by: org.springframework.core.serializer.support.SerializationFailedException: Failed to deserialize payload. Is the byte array a result of corresponding serialization for DefaultDeserializer?; nested exception is java.io.EOFException
	at org.springframework.core.serializer.support.DeserializingConverter.convert(DeserializingConverter.java:78)
	at org.springframework.core.serializer.support.DeserializingConverter.convert(DeserializingConverter.java:36)
	at org.springframework.data.redis.serializer.JdkSerializationRedisSerializer.deserialize(JdkSerializationRedisSerializer.java:79)
	... 35 more
Caused by: java.io.EOFException

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用tomcat运行自己servlet组件的时候，请求错误。

1

class="cursor-pointer"> 详细描述

class="cursor-pointer"> 错误截图

class="cursor-pointer"> 源码

package com.servlet.xxxservlet;

import com.servlet.dao.EmpDao;
import com.servlet.dao.EmpDaoImpl;
import com.servlet.entity.Emp;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.List;

/**
 * 路径规范：
 * 查询员工：/findEmp.do
 * 增加员工：/addEmp.do
 */
public class MainServlet extends HttpServlet {
    @Override
    protected void service(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        //获取请求路径：
        String path=req.getServletPath();
        //根据规范处理路径：
        if("/findEmp.do".equals(path)){
            findEmp(req,resp);
        }else if("/addEmp.do".equals(path)){
            addEmp(req,resp);
        }else {
            //该异常抛给服务器，服务器可以统一处理异常
            throw new RuntimeException("查无此页");

        }

    }
    protected void findEmp(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        System.out.println(".................");
        //1.接收参数
        // 2.处理业务
        EmpDao empDao =new EmpDaoImpl();
        List<Emp> list=empDao.findAll();
        // 3.输出响应
        resp.setContentType("text/html;charSet=utf-8");
        PrintWriter printWriter =resp.getWriter();
        printWriter.println("<a href='add_emp.html'>增加</a>");
        printWriter.println("<table border='1' cellspacing='0' width='40%'>");
        printWriter.println("   <tr>");
        printWriter.println("       <td>编号</td>");
        printWriter.println("       <td>姓名</td>");
        printWriter.println("       <td>职位</td>");
        printWriter.println("       <td>工资</td>");
        printWriter.println("   </tr>");
        if(list!=null){
            for(Emp emp:list){
                printWriter.println("   <tr>");
                printWriter.println("       <td>"+emp.getEmpno()+"</td>");
                printWriter.println("       <td>"+emp.getEname()+"</td>");
                printWriter.println("       <td>"+emp.getJob()+"</td>");
                printWriter.println("       <td>"+emp.getSal()+"</td>");
                printWriter.println("   </tr>");
            }
        }
        printWriter.println("</table>");
        printWriter.close();

    }
    protected void addEmp(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        System.out.println("000000000000000");
        req.setCharacterEncoding("utf-8");
        System.out.println(".........");
        //接受参数
        String name =req.getParameter("name");
        String job =req.getParameter("job");
        String sal =req.getParameter("sal");
        //处理业务
        Emp emp=new Emp();
        emp.setEname(name);
        emp.setJob(job);
        if(sal!=null&&!sal.equals("")){
            emp.setSal(new Double(sal));
        }
        EmpDao empDao =new EmpDaoImpl();
        empDao.save(emp);
        //输出响应
        //resp.setContentType("text/html;charSet=utf-8");
        //PrintWriter printWriter=resp.getWriter();
        //printWriter.println("<p>保存成功</p>");
        //printWriter.close();
        //重定向到查询页面，就是建议游览器去访问查询页面
        //当前：/servlet/addEmp
        //目标：/servlet/findEmp
        resp.sendRedirect("/findEmp.do");
    }
}
<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<!--当前：/servlet/add_emp.html
    目标：/servlet/addEmp-->
<form action="addEmp.do" method="post">
    <p>
        姓名：<input type="text" name="name"/>
    </p>
    <p>
        职位：<input type="text" name="job"/>
    </p>
    <p>
        月薪：<input type="text" name="sal"/>
    </p>
    <p>
        <input type="submit" value="保存"/>
    </p>
</form>
</body>
</html>
  <servlet>
    <servlet-name>main</servlet-name>
    <servlet-class>com.servlet.xxxservlet.MainServlet</servlet-class>
    <!--启动时加载此Servlet，中间的数字是加载的顺序-->
    <load-on-startup>1</load-on-startup>
  </servlet>
  <servlet-mapping>
    <servlet-name>main</servlet-name>
    <url-pattern>*.do</url-pattern>
  </servlet-mapping>

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关联查询引用的数据混乱

1

spring mybatis

class="cursor-pointer"> 详细描述

class="cursor-pointer"> 错误截图

class="cursor-pointer"> 源码

  <!-- 根据分页数据start 和size查询数据 -->
    <select id="findByPage" parameterType="Map" resultType="Student">
        select * FROM students
        <if test="start!=null and size!=null">
            limit #{start},#{size}
        </if>
    </select>

    <!-- 查询用户记录总数 -->
    <select id="selectCount" resultType="int">
        select count(*) FROM `students`
    </select>

    <select id="findById" parameterType="long" resultType="Student">
        SELECT * FROM students WHERE id = #{id}
    </select>

    <select id="findByName" parameterType="java.lang.String" resultType="Student">
        SELECT * FROM students WHERE name LIKE '%${value}%'
    </select>

    <select id="findByNum" parameterType="java.lang.String" resultType="Student">
        SELECT * FROM students WHERE num = #{num}
    </select>

    <insert id="insertStudent" parameterType="Student">
        INSERT INTO students(name,qq,type,admission_time,school,num,daily,declaration,elder,knew_from,create_at) VALUE
        (#{name},#{qq},#{type},#{admissionTime},#{school},#{num},#{daily},#{declaration},#{elder},#{knewFrom},#{createAt})
        <selectKey keyProperty="id" order="AFTER" resultType="java.lang.Long">
            select last_insert_id()
        </selectKey>
    </insert>

    <delete id="deleteStudent" parameterType="java.lang.Long">
        DELETE FROM students WHERE id = #{id}
    </delete>

    <update id="updateStudent" parameterType="Student">
        UPDATE students

        <set><!--set标签会去除只有最后一个条件的,-->
            <if test="updateAt!=null and updateAt!=''">
                update_at=#{updateAt},
                <if test="name!= null and name!=''">name = #{name},</if>
                <if test="QQ!= null and QQ!=''">QQ = #{QQ},</if>
                <if test="type!= null and type!=''">type = #{type},</if>
                <if test="admissionTime!= null and admissionTime!=''">admission_time = #{admissionTime},</if>
                <if test="school!= null and school!=''">school = #{school},</if>
                <if test="num!= null and num!=''">num = #{num},</if>
                <if test="daily!= null and daily!=''">daily = #{daily},</if>
                <if test="declaration!= null and declaration!=''">declaration = #{declaration},</if>
                <if test="elder!= null and elder!=''">elder = #{elder},</if>
                <if test="knewFrom!= null and knewFrom!=''">knew_from = #{knewFrom},</if>
            </if>
        </set>

        <where><!--where标签会去除第一个条件的and和or-->
            <if test="id!=null">AND id=#{id}</if>
        </where>
    </update>

</mapper>

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日志部署到服务器打包jar包报错

1

class="cursor-pointer"> 详细描述

class="cursor-pointer"> 错误截图

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mybatis配置文件mapper.xml里每一项的作用

0

1

mybatis

class="cursor-pointer"> 详细描述

class="cursor-pointer"> 错误截图

class="cursor-pointer"> 源码

package mybatis;

import java.io.IOException;
import java.io.InputStream;

import org.apache.ibatis.io.Resources;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;

public class testStudent {
    public static void main(String[] args) throws IOException
    {
        String resource = "mybatis-config.xml";
        InputStream inputStream = Resources.getResourceAsStream(resource);
        SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(inputStream);
        SqlSession session = sqlSessionFactory.openSession();
        try
        {
            Student stu = session.selectOne("mybatis.mapper.select", 1);
            System.out.println(stu.getName());
            stu = session.selectOne("mybatis.mapper.select", 2);
            System.out.println(stu.getName());
        }
        finally
        {
            session.close();
        }
    }
}

Exception in thread "main" org.apache.ibatis.exceptions.PersistenceException: 
### Error querying database.  Cause: org.apache.ibatis.builder.IncompleteElementException: Could not find result map mybatis.Student
### Cause: org.apache.ibatis.builder.IncompleteElementException: Could not find result map mybatis.Student
	at org.apache.ibatis.exceptions.ExceptionFactory.wrapException(ExceptionFactory.java:30)
	at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:150)
	at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:141)
	at org.apache.ibatis.session.defaults.DefaultSqlSession.selectOne(DefaultSqlSession.java:77)
	at mybatis.testStudent.main(testStudent.java:20)
Caused by: org.apache.ibatis.builder.IncompleteElementException: Could not find result map mybatis.Student
	at org.apache.ibatis.builder.MapperBuilderAssistant.getStatementResultMaps(MapperBuilderAssistant.java:346)
	at org.apache.ibatis.builder.MapperBuilderAssistant.addMappedStatement(MapperBuilderAssistant.java:290)
	at org.apache.ibatis.builder.xml.XMLStatementBuilder.parseStatementNode(XMLStatementBuilder.java:109)
	at org.apache.ibatis.session.Configuration.buildAllStatements(Configuration.java:788)
	at org.apache.ibatis.session.Configuration.getMappedStatement(Configuration.java:719)
	at org.apache.ibatis.session.Configuration.getMappedStatement(Configuration.java:714)
	at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:147)
	... 3 more
Caused by: java.lang.IllegalArgumentException: Result Maps collection does not contain value for mybatis.Student
	at org.apache.ibatis.session.Configuration$StrictMap.get(Configuration.java:888)
	at org.apache.ibatis.session.Configuration.getResultMap(Configuration.java:640)
	at org.apache.ibatis.builder.MapperBuilderAssistant.getStatementResultMaps(MapperBuilderAssistant.java:344)
	... 9 more