在实现查找待审批请假单中出现的问题

在ResponseUtils中进行调试出现以下情况

this转换为字符串时报错，第59行提示错误代码是抛出运行时异常：

throw new RuntimeException(e);

我将老师文件中的ResponseUtils代码也复制过来运行依然报错。具体ResponseUtils代码如下：

package com.imooc.oa.utils;

import com.fasterxml.jackson.annotation.JsonInclude;
import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.databind.ObjectMapper;

import java.util.LinkedHashMap;
import java.util.Map;

public class ResponseUtils {
    private String code;
    private String message;
    private Map data =new LinkedHashMap<>();
    public ResponseUtils(){
        this.code="0";
        this.message="success";

    }
    public ResponseUtils(String code,String message){
        this.setCode(code);
        this.setMessage(message);
    }
    public ResponseUtils put(String key,Object value){
        this.data.put(key,value);
        return this;
    }

    public String getCode() {
        return code;
    }

    public void setCode(String code) {
        this.code = code;
    }

    public String getMessage() {
        return message;
    }

    public void setMessage(String message) {
        this.message = message;
    }

    public Map getData() {
        return data;
    }

    public void setData(Map data) {
        this.data = data;
    }

    public String toJsonString(){
        ObjectMapper objectMapper=new ObjectMapper();
        objectMapper.setSerializationInclusion(JsonInclude.Include.NON_NULL);
        try {
            String json=objectMapper.writeValueAsString(this);
            return json;
        } catch (JsonProcessingException e) {
            throw new RuntimeException(e);
        }
    }
}

对于在pom.xml中的配置如下：

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>com.imooc</groupId>
    <artifactId>imooc-oa</artifactId>
    <version>1.0-SNAPSHOT</version>

    <properties>
        <maven.compiler.source>8</maven.compiler.source>
        <maven.compiler.target>8</maven.compiler.target>
    </properties>

<!--    引入阿里云路径 开始-->
    <repositories>
        <repository>
            <id>aliyun</id>
            <name>aliyun</name>
            <url>https://maven.aliyun.com/repository/public</url>
        </repository>
    </repositories>
    <pluginRepositories>
        <pluginRepository>
            <id>aliyun</id>
            <name>aliyun</name>
            <url>https://maven.aliyun.com/repository/public</url>
        </pluginRepository>
    </pluginRepositories>

    <dependencies>
        <!--引入java servlet依赖-->
        <dependency>
            <groupId>javax.servlet</groupId>
            <artifactId>javax.servlet-api</artifactId>
            <version>3.1.0</version>
            <scope>provided</scope>
        </dependency>
        <!--引入mybatis依赖-->
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis</artifactId>
            <version>3.5.3</version>
        </dependency>
        <!--引入jdbc驱动-->
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>8.0.26</version>
        </dependency>
        <!--引入junit4单元测试框架-->
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.13.2</version>
            <scope>test</scope>
        </dependency>
        <!--引入logback日志输出组件-->
        <dependency>
            <groupId>ch.qos.logback</groupId>
            <artifactId>logback-classic</artifactId>
            <version>1.2.3</version>
        </dependency>
        <!--Druid数据库连接池-->
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>druid</artifactId>
            <version>1.2.8</version>
        </dependency>
        <!--Jackson Json处理包-->
        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-databind</artifactId>
            <version>2.12.3</version>
        </dependency>
        <!--Apache 加密解密组件-->
        <dependency>
            <groupId>commons-codec</groupId>
            <artifactId>commons-codec</artifactId>
            <version>1.15</version>
        </dependency>
    </dependencies>
</project>

同学你好，测试并没有复现同学的问题，同学在pom.xml中添加如下依赖试试

<dependency>
    <groupId>com.fasterxml.jackson.datatype</groupId>
    <artifactId>jackson-datatype-jsr310</artifactId>
    <version>2.6.0</version>
</dependency>

如果还不可以，同学可以下载源码，运行源码试试，看看是否会出现该问题

祝学习愉快~

问题解决了，可是还是不知道问题出在哪里。。。，我先把自己LeaveFormServlet，LeaveForm，ResponseUtils和pom.xml这四个文件先全部注释掉了，然后将老师源代码文件中的这个四个文件的代码复制过来然后运行，显示正常，然后我将自己的先前已经注释掉的代码每恢复一个运行一次，直到最后全部恢复，能够正常运行，期间没有修改任何代码，所以虽然问题解决了，但是不知道原因