找出两个字符串中最大公共子字符串,如

import java.util.ArrayList;
 import java.util.List;//找出两个字符串中最大公共子字符串,如"abccade","dgcadde"的最大子串为"cad"
 public class ZuiDaZiChuan { public static void main(String args[]) {
  String str1 = "abccade";
   String str2 = "dgcadde";  List<String> str1Sub = new ArrayList<String>();
   List<String> str2Sub = new ArrayList<String>();  List<String> listSame = new ArrayList<String>();
  for (int i = 0; i <= str1.length(); i++) {
    for (int j = i; j <= str1.length(); j++) {
     str1Sub.add(str1.substring(i, j));
    }
   }  for (int i = 0; i <= str2.length(); i++) {
    for (int j = i; j <= str2.length(); j++) {
     str2Sub.add(str2.substring(i, j));
    }
   }  for (int i = 0; i < str1Sub.size(); i++) {
    for (int j = 0; j < str2Sub.size(); j++) {
     if (str1Sub.get(i).equals(str2Sub.get(j))) {
      listSame.add(str1Sub.get(i));
     }
    }
   }  int maxId = 0;
   int maxValue = 0;
   for (int i = 0; i < listSame.size(); i++) {
    if (listSame.get(i).length() > maxValue) {
     maxId = i;
     maxValue = listSame.get(i).length();
    }  }
  System.out.print(listSame.get(maxId));
 }
}