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前提回顾建议大家从【JVM研究系列-Java各种类型对象占用内存情况分析】开始学习比较好，这样子会有一个承接和过度。根据前面的学习的内存占用计算规则，可以计算出一个对象在内存中的占用空间大小情况，下面举例分析下Java中的Enum, ArrayList及HashMap的内存占用情况，读者可以仿照分析...

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