java查找最长公共子串

java查找两个字符串的最长公共子串

package test;

import java.util.Vector;

public class test {

    public static String getChildStr(String str1, String str2)
    {
        int [][]record=new int[str1.length()][str2.length()];
        int maxLen = 0, maxEnd = 0;
        for (int i = 0; i < str1.length(); ++i)
        for (int j = 0; j < str2.length(); ++j)
        {
            if (str1.charAt(i) == str2.charAt(j))
            {
                if (i == 0 || j == 0)
                {
                    record[i][j]= 1;
                }
                else
                {
                    record[i][j] = record[i - 1][j - 1] + 1;
                }
            }
            else
            {
                record[i][j] = 0;
            }

            if (record[i][j] > maxLen)
            {
                maxLen = record[i][j];
                maxEnd = j;
            }
        }
        return str2.substring(maxEnd - maxLen + 1, maxLen);
    }
    public static void main(String[] args) {
        long start= System.currentTimeMillis();
        System.out.println(getChildStr("ajhf;ajkdjan;kjdfck;fjdfnkjdasjfo;iaejfaeiojrdfoijoifdjvo;iaejroifjfvaoedrjvodifjv;ILOVEYOU","ILOVEyou"));
        long end=System.currentTimeMillis();
        System.out.println(end-start);
    }
}