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Java 最常见的面试题：两个对象的 hashCode()相同，则 equals()也一定为 true，对吗？

不对，两个对象的 hashCode()相同，equals()不一定 true。代码示例：String str1 = "通话"; String str2 = "重地"; System.out.println(String.format("str1：%d | str2：%d", str1.hashCod...

[帮助文档] 管道任务同步读取源表时报错java.sql.SQLExceptionORA-08103

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直接在方法中声明这个对象,SpringMvc就自动会把属性赋值到这个对象里面。个人简介我是一名java开发工程师，目前35K，目前做的是无人驾驶，欢迎和大家一起交流开发技术，一起高薪就业，我们还有一起打妖怪的群哦，还有“it面试题”小程序哦! 以上就是本文的全部内容，希望对大家的学习有所帮助，也希...

Java面试题：哪些对象可以作为GC Roots？

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Java常见面试题：ThreadLocal对象处理

ThreadLocal对象处理 ThreadLocal的本身作用就是进行操作对象信息保存，但是它与传统的信息保存不同，它不仅仅保存的是一个引用对象，而且还保存有一个当前对象，也就是说进行数据保存的时候ThreadLocal更像Map集合。范例：引用的麻烦现在Demo类中的print（）方法核心的...

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