Comments (3)
JerryLead
commented on September 17, 2024
对，我这里可能没有说清楚，其实我的意思是：如果很难或者不能在上某个类型上定义正确的partition()，那么这个类型不能当作Key使用。Hadoop里面也是一样，一些自定的class可以当作key使用，但如果无法在上面定义partition()，那么就不能当作key。
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lqian
commented on September 17, 2024
那段注释是java数组的hashcode是基于数组的标示符而不是基于数组内容（元素），使用array作为分区键会产生不可预料不正确的结果。其实不光是数组，map作为分区键也不合适。这个东西可以引申一下，如果作为分区键的class很难产生value一致排序的分区，则不适合做分区键
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JerryLead
commented on September 17, 2024
@lqian 谢谢建议，下次修改时加上
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