Java字母加数字组合比较大小

package testsource; 
 
import java.util.ArrayList; 
import java.util.List; 
 
/** 
 * 
 * @author Waston Xu 
 * @date 2011-4-15 上午10:48:21 
 */ 
public class MyString implements Comparable<MyString> { 
  private final String string; 
  private List<Object> list; 
 
  public MyString(String string) { 
    this.string = string; 
    trimString2List(); 
  } 
 
  private void trimString2List() { 
    list = new ArrayList<Object>(); 
    Integer num = 0; 
    StringBuffer sb = new StringBuffer(); 
    for (int i = 0; i < this.string.length(); i++) { 
      char c = this.string.charAt(i); 
      if (c > 47 && c < 58) { 
        if (sb.length() != 0) { 
          list.add(sb); 
          sb = new StringBuffer(); 
        } 
        num = num * 10 + (c - '0'); 
        continue; 
      } else { 
        if (num != 0) { 
          list.add(num); 
          num = 0; 
        } 
        sb.append(c); 
        continue; 
      } 
    } 
    if (sb.length() != 0) { 
      list.add(sb); 
      sb = new StringBuffer(); 
    } else if (num != 0) { 
      list.add(num); 
      num = 0; 
    } 
  } 
 
  /* 
   * 在仔细的观看了String的compareTo方法后，本来打算不调用其API进行编程， 
   * 但是考虑到出现"a02"和"a2"这样的情况还是使用其API中的方式解决。 
   */ 
  private int compareToLikeString(String s) { 
    int len1 = string.length(); 
    int len2 = s.length(); 
    int n = Math.min(len1, len1); 
    if (n > 0) { 
      int k = 0; 
      while (k < n) { 
        char c1 = string.charAt(k); 
        char c2 = s.charAt(k); 
        if (c1 != c2) 
          return c1 - c2; 
        k++; 
      } 
    } 
 
    return len1 - len2; 
  } 
 
  @Override 
  public int compareTo(MyString anotherString) { 
    int len1 = list.size(); 
    int len2 = anotherString.list.size(); 
    int n = Math.min(len1, len2); 
 
    int mark = 0; 
    if (n > 0) { 
      int i = 0; 
      while (i < n) { 
        Object o1 = list.get(i); 
        Object o2 = anotherString.list.get(i); 
        if (o1 instanceof Integer && o2 instanceof Integer) { 
          mark = (Integer) o1 - (Integer) o2; 
        } else { 
          mark = o1.toString().compareTo(o2.toString()); 
        } 
        if (mark != 0) 
          return mark; 
        i++; 
      } 
    } 
    return compareToLikeString(anotherString.string); 
    //return string.compareTo(anotherString.string); 
    /* 如果这样写会有个弊端就是出现"a02"和"a2"这样的情况，肯定是前面的小*/ 
    //return string.length() - anotherString.string.length(); 
  } 
 
  public static void main(String[] args) { 
    String s1 = "b9c"; 
    String s2 = "b09c"; 
    MyString m1 = new MyString(s1); 
    MyString m2 = new MyString(s2); 
 
    System.out.println(m1.compareTo(m2)); 
  } 
}