HashMap.java 

int capacity = 1;    int initialCapacitys[] = {1,2,3,4,5,6,7,8,9,10,11,13,15,16,17,26,31,32,33,50,60,63,64,65};    for(int initialCapacity : initialCapacitys){    while (capacity < initialCapacity)        capacity <<= 1;            System.out.println("initialCapacity:" + initialCapacity + ", capacity:" + capacity);}    /*this.loadFactor = loadFactor;threshold = (int)Math.min(capacity * loadFactor, MAXIMUM_CAPACITY + 1);table = new Entry[capacity]; */

 

输出结果：

initialCapacity:1, capacity:1

initialCapacity:2, capacity:2

initialCapacity:3, capacity:4

initialCapacity:4, capacity:4

initialCapacity:5, capacity:8

initialCapacity:6, capacity:8

initialCapacity:7, capacity:8

initialCapacity:8, capacity:8

initialCapacity:9, capacity:16

initialCapacity:10, capacity:16

initialCapacity:11, capacity:16

initialCapacity:13, capacity:16

initialCapacity:15, capacity:16

initialCapacity:16, capacity:16

initialCapacity:17, capacity:32

initialCapacity:26, capacity:32

initialCapacity:31, capacity:32

initialCapacity:32, capacity:32

initialCapacity:33, capacity:64

initialCapacity:50, capacity:64

initialCapacity:60, capacity:64

initialCapacity:63, capacity:64

initialCapacity:64, capacity:64

initialCapacity:65, capacity:128

 

 

 

ConcurrentHashMap.java

 

int concurrencyLevel = 16; //默认是16int MIN_SEGMENT_TABLE_CAPACITY = 2;      int sshift = 0;int ssize = 1;while (ssize < concurrencyLevel) {    ++sshift;    ssize <<= 1;}              int initialCapacitys[] = {1,10,16,31,32,33,63,64,65,127,128,129,256,257,512,513,1024,1025,2048,4096,8192,16384};      for(int initialCapacity : initialCapacitys){    int c = initialCapacity / ssize;    if (c * ssize < initialCapacity)        ++c;              int cap = MIN_SEGMENT_TABLE_CAPACITY;              while (cap < c)        cap <<= 1;              System.out.println("initialCapacity:" + initialCapacity + ", c:" + c + ", cap:" + cap + ", ssize:" + ssize);}      // create segments and segments[0]/*Segment
    
      s0 =    new Segment
     
      (loadFactor, (int)(cap * loadFactor),                     (HashEntry
      
       [])new HashEntry[cap]);Segment
       
        [] ss = (Segment
        
         [])new Segment[ssize];*/
        
       
      
     
    

输出结果：

initialCapacity:1, c:1, cap:2, ssize:16

initialCapacity:10, c:1, cap:2, ssize:16

initialCapacity:16, c:1, cap:2, ssize:16

initialCapacity:31, c:2, cap:2, ssize:16

initialCapacity:32, c:2, cap:2, ssize:16

initialCapacity:33, c:3, cap:4, ssize:16

initialCapacity:63, c:4, cap:4, ssize:16

initialCapacity:64, c:4, cap:4, ssize:16

initialCapacity:65, c:5, cap:8, ssize:16

initialCapacity:127, c:8, cap:8, ssize:16

initialCapacity:128, c:8, cap:8, ssize:16

initialCapacity:129, c:9, cap:16, ssize:16

initialCapacity:256, c:16, cap:16, ssize:16

initialCapacity:257, c:17, cap:32, ssize:16

initialCapacity:512, c:32, cap:32, ssize:16

initialCapacity:513, c:33, cap:64, ssize:16

initialCapacity:1024, c:64, cap:64, ssize:16

initialCapacity:1025, c:65, cap:128, ssize:16

initialCapacity:2048, c:128, cap:128, ssize:16

initialCapacity:4096, c:256, cap:256, ssize:16

initialCapacity:8192, c:512, cap:512, ssize:16

initialCapacity:16384, c:1024, cap:1024, ssize:16

 

 

2013-05-14

 

 

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