public class String

{

       …

    public int compareTo(String anotherString) {

       int len1 = count;

       int len2 = anotherString.count;

       //n为两个字符串长度的最小者

       int n = Math.min(len1, len2);

       //获取字符数组

       char v1[] = value;

       char v2[] = anotherString.value;

       //取偏依位置

    /** The offset is the first index of the storage that is used. */

       //offset 是第一个存储索引

       int i = offset;

       int j = anotherString.offset;

       //如果i == j

       //这里可能是判断取同一内存中两个字符串的情景。。。

       // A   <--   <----

       // B    s1      |

       // C   <--      |

       // D            s2

       // E            |

       // F            |

       // G   <----------

       // 可能这种情况 i = j

       if (i == j) {

           int k = i;

           int lim = n + i;

           while (k < lim)

              {

                     char c1 = v1[k];

                     char c2 = v2[k];

                     if (c1 != c2) file://直到找到一个不相等的字符，返回c1 - c2

                            return c1 - c2;

                     k++;

           }

       } else {

           while (n-- != 0) file://直到两个字符串长度记数为0

              {

                     char c1 = v1[i++]; file://分别取字符

                     char c2 = v2[j++];

                     if (c1 != c2) {  //发现不相等，立即返回c1 - c2;

                            return c1 - c2;

                     }

           }

       }

       return len1 - len2;

//最后这里可能出现的情况是: 两个字符串比较完之后还没有得到结果。相等的情况

    }

…

}//end of class String

字符

Char值

Byte[]值

按Byte[]合成的值

我

25105

[50:46]

[-5046]

爱

29233

[80:82]

[-8082]

北

21271

[79:79]

[-7979]

京

20140

[66:87]

[-6687]

天

22825

[52:20]

[-5220]

安

23433

[80:78]

[-8078]

门

38376

[61:59]

[-6159]

A

65

[-65]

[65]

B

66

[-66]

[66]

C

67

[-67]

[67]

D

68

[-68]

[68]

private static String __ENCODE__ = "GBK"; file://一定要是GBK

private static String __SERVER_ENCODE__ = "GB2312"; file://服务器上的缺省编码

/*

比较两字符串

*/

       public int compare(String s1, String s2)

       {

              String m_s1 = null, m_s2 = null;

              try

              {

                     //先将两字符串编码成GBK

                     m_s1 = new String ( s1.getBytes(__SERVER_ENCODE__), __ENCODE__);

                     m_s2 = new String ( s2.getBytes(__SERVER_ENCODE__), __ENCODE__);

              }

              catch( Exception ex)

              {

                     return s1.compareTo(s2);

              }

              int res = chineseCompareTo(m_s1, m_s2);

              System.out.println("比较：" + s1 + " | " + s2 + "==== Result: " + res);

              return res;

       }

//获取一个汉字/字母的Char值

       public static int getCharCode(String s)

       {

              if (s==null && s.equals(“”)) return -1; file://保护代码

byte [] b = s.getBytes();

              int value = 0;

              //保证取第一个字符（汉字或者英文）

              for (int i = 0; i < b.length && i <= 2; i ++)

              {

                     value = value * 100 + b[i];

              }

              return value;

       }

//比较两个字符串

       public int chineseCompareTo(String s1, String s2)

       {

              int len1 = s1.length();

              int len2 = s2.length();

              int n = Math.min(len1, len2);

              for (int i = 0; i < n; i ++)

              {

                     int s1_code = getCharCode(s1.charAt(i) + "");

                     int s2_code = getCharCode(s2.charAt(i) + "");

                     if (s1_code != s2_code) return s1_code - s2_code;

              }

              return len1 - len2;

       }