密码合格验证程序

package HUAWEI;

import java.util.Scanner;

public class Main1_1 {
public static void main(String[] args) {
Scanner scanner = new Scanner(System.in);
StringBuilder builder = new StringBuilder();
while (scanner.hasNext()) {
String input = scanner.nextLine();
System.out.println(passwordValidate(input));
}
scanner.close();

}

private static String passwordValidate(String input) {
final String OK = "OK";
final String NG = "NG";

// 长度超过8
if (input == null || input.length() < 9) {
return NG;
}

int num1 = 0,num2 = 0,num3 = 0,num4 = 0;

// 统计
for (int i = 0; i < input.length(); i++) {
char ch = input.charAt(i);
if (ch >= 'A' && ch <= 'Z') {
num1 = 1;
} else if (ch >= 'a' && ch <= 'z') {
num2 = 1;
} else if (ch >= '0' && ch <= '9') {
num3 = 1;
} else {
num4 = 1;
}
}

// 小于三种
if ((num1 + num2 + num3 + num4) < 3) {
return NG;
}

System.out.println("字符串的长度："+input.length());
for (int i = 0; i < input.length() - 3; i++) {
String s1 = input.substring(i, i + 3);
String s2 = input.substring(i + 3, input.length());
System.out.println("第"+i+"次"+s1+"..."+s2);
if (s2.contains(s1)) {
return NG;
}
}
return OK;
}
}