常用问题汇总

1.Object转换json后，发现有些是"" 有些是null

上网上查了一下 原因：

https://blog.csdn.net/qq_18977307/article/details/79699739

2.时间转到前端为 2019-08-03T03:11:11.000+0000

解决方案：

@JsonFormat(pattern="yyyy-MM-dd HH:mm:ss",timezone="GMT+8")

https://www.cnblogs.com/mracale/p/9828346.html

3.springBoot 加入页面后请求报错

 2019/09/30-17:20:43 [http-nio-8099-exec-8] ERROR org.thymeleaf.TemplateEngine- [THYMELEAF][http-nio-8099-exec-8] Exception processing template "deviceList": Could not parse as expression: "

解决方案：

感谢这位博主的分享 ：
https://blog.csdn.net/ystyaoshengting/article/details/84773952

把cols后的[[ ]]变为
[
    [
    ]
]

4.mybatis 打印日志

<?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>
    <settings>
        <!-- 打印查询语句 -->
        <setting name="logImpl" value="STDOUT_LOGGING"/>
    </settings>
    <!-- 环境配置：事务管理器和数据源配置 -->
    <environments default="development">
        <environment id="development">
            <transactionManager type="JDBC"/>
            <dataSource type="POOLED">
                <property name="driver" value="com.mysql.jdbc.Driver"/>
    <!-- 映射器 -->
    <mappers>
        <package name="com.*.*.dao"/>
    </mappers>
</configuration>