Java问题记录-阿里云

Java【问题记录 02】对象封装+固定排序+list All elements are null引起的异常处理+Missing artifact com.sun:tools:jar:1.8.0

why开发问题并不是经常遇到的，有技术问题，也有业务问题，记录一下，以备不时之需。1 对象封装将B类型的对象封装成A类型的对象，常用于Map对象封装成Entity对象，这里有Gson和JSON两种方式：A_Class a_Object = new Gson().fromJson(new Gson()...

Java【问题记录 04】时间戳类型字符串{Timestamp@15601}2021-07-14 18:56:53.0变成带T的Object类型2021-07-14T10:56:53.000+0000

why两个平台，一个平台直接查询数据库，另一个平台通过接口调用查询数据，导致时间戳 Timestamp 格式字符串传输后变 yyyy-MM-ddTHH:mm:ss.000+0000 日期格式，出现这种问题的可能原因是：从数据库查询出来的数据没有进行封装，直接使用Map<String, Obje...

「大师课」搞定 Java 开发基础

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Java Spring Boot 2.6.0开发实战-1024程序员节创造营公益课

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Java【问题记录 03】三目运算符失效问题刨根问底（及NPE分析）

我的开发问题记录里有这么一个问题，当时项目着急就没用三目，也没查找原因，那时的bean.getCounter()返回值也不知道是啥了，没有关系，咱们彻底分析一下这个问题。// 三目失效 String counter = bean.getCounter() == "1" ? "第一次" : "第二次"...

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更新时间 2024-03-21 09:49:02

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