《重构：改善既有代码的设计》——关于代码注释的唠叨

1 string personName;    // 人员姓名

 1     /**
 2      * Compares two strings lexicographically.
 3      * The comparison is based on the Unicode value of each character in
 4      * the strings. The character sequence represented by this
 5      * {@code String} object is compared lexicographically to the
 6      * character sequence represented by the argument string. The result is
 7      * a negative integer if this {@code String} object
 8      * lexicographically precedes the argument string. The result is a
 9      * positive integer if this {@code String} object lexicographically
10      * follows the argument string. The result is zero if the strings
11      * are equal; {@code compareTo} returns {@code 0} exactly when
12      * the {@link #equals(Object)} method would return {@code true}.
13      * <p>
14      * This is the definition of lexicographic ordering. If two strings are
15      * different, then either they have different characters at some index
16      * that is a valid index for both strings, or their lengths are different,
17      * or both. If they have different characters at one or more index
18      * positions, let <i>k</i> be the smallest such index; then the string
19      * whose character at position <i>k</i> has the smaller value, as
20      * determined by using the &lt; operator, lexicographically precedes the
21      * other string. In this case, {@code compareTo} returns the
22      * difference of the two character values at position {@code k} in
23      * the two string -- that is, the value:
24      * <blockquote><pre>
25      * this.charAt(k)-anotherString.charAt(k)
26      * </pre></blockquote>
27      * If there is no index position at which they differ, then the shorter
28      * string lexicographically precedes the longer string. In this case,
29      * {@code compareTo} returns the difference of the lengths of the
30      * strings -- that is, the value:
31      * <blockquote><pre>
32      * this.length()-anotherString.length()
33      * </pre></blockquote>
34      *
35      * @param   anotherString   the {@code String} to be compared.
36      * @return  the value {@code 0} if the argument string is equal to
37      *          this string; a value less than {@code 0} if this string
38      *          is lexicographically less than the string argument; and a
39      *          value greater than {@code 0} if this string is
40      *          lexicographically greater than the string argument.
41      */
42     public int compareTo(String anotherString) {
43         int len1 = value.length;
44         int len2 = anotherString.value.length;
45         int lim = Math.min(len1, len2);
46         char v1[] = value;
47         char v2[] = anotherString.value;
48 
49         int k = 0;
50         while (k < lim) {
51             char c1 = v1[k];
52             char c2 = v2[k];
53             if (c1 != c2) {
54                 return c1 - c2;
55             }
56             k++;
57         }
58         return len1 - len2;
59     }