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程序员总是有踩不完的坑，今天就在HashSet这个类上栽了跟头。终究还是自己对HashSet集合理解不够深刻。下面就来说一下问题及原因。

Question

首先用一个简单的例子描述一下问题。

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public class HashCodeTest {
    int hashCode = 0;
    //重写Object对象中的save方法
    @Override
    public int hashCode() {
        return ++hashCode;
    }
    public static void main(String[] args) {
        Set<HashCodeTest> hashCodeTests = new HashSet<>();
        HashCodeTest hashCodeTest = new HashCodeTest();
        System.out.println(hashCodeTest.hashCode());
        hashCodeTests.add(hashCodeTest);
        System.out.println(hashCodeTests.size());
        //迭代
        Iterator<HashCodeTest> iterator = hashCodeTests.iterator();
        while (iterator.hasNext()) {
            iterator.next();
            iterator.remove();
        }
        System.out.println(hashCodeTests.size());
    }
}
文章目錄
  1. 1. Question