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理解奇怪的Java哈希函数

以下是哈希函数的源代码java.util.HashMap.评论很好地解释了它的成就.但怎么样?什么是^>>>运营商在做什么?有人可以解释代码实际上如何评论所说的内容吗?

/**
 * Applies a supplemental hash function to a given hashCode, which
 * defends against poor quality hash functions.  This is critical
 * because HashMap uses power-of-two length hash tables, that
 * otherwise encounter collisions for hashCodes that do not differ
 * in lower bits. Note: Null keys always map to hash 0, thus index 0.
 */
static int hash(int h) {
    // This function ensures …
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java hash

33
推荐指数
3
解决办法
7243
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理解方法注释java 8中HashMap类的hash()方法

 /**
     * Computes key.hashCode() and spreads (XORs) higher bits of hash
     * to lower.  Because the table uses power-of-two masking, sets of
     * hashes that vary only in bits above the current mask will
     * always collide. (Among known examples are sets of Float keys
     * holding consecutive whole numbers in small tables.)  So we
     * apply a transform that spreads the impact of higher bits
     * downward. There is a tradeoff between speed, utility, and
     * quality of bit-spreading. …
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java hash hashmap data-structures

10
推荐指数
1
解决办法
600
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