在此之前，您可以阅读生成一次性密码或唯一标识 URL 文章以更好地理解。
很多时候我们忘记密码，我们选择忘记密码选项，很快我们就会在我们注册的电子邮件 ID 或电话号码中获得一个新密码。登录我们的帐户。每次我们得到不同的密码。
有时我们在从网上商店或更多方式购物时访问我们的银行账户，为了验证我们从银行账户的转换，他们通过我们注册的电话号码向我们发送 OTP（一次性密码）。或我们的电子邮件 ID，很快。
以下代码说明了如何立即生成此类密码和 OTP，以及在需要时可以使用哪些代码。
方法一：
解释密码生成的Java程序
// Java code to explain how to generate random
// password
// Here we are using random() method of util
// class in Java
import java.util.*;
public class NewClass
{
public static void main(String[] args)
{
// Length of your password as I have choose
// here to be 8
int length = 10;
System.out.println(geek_Password(length));
}
// This our Password generating method
// We have use static here, so that we not to
// make any object for it
static char[] geek_Password(int len)
{
System.out.println("Generating password using random() : ");
System.out.print("Your new password is : ");
// A strong password has Cap_chars, Lower_chars,
// numeric value and symbols. So we are using all of
// them to generate our password
String Capital_chars = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
String Small_chars = "abcdefghijklmnopqrstuvwxyz";
String numbers = "0123456789";
String symbols = "!@#$%^&*_=+-/.?<>)";
String values = Capital_chars + Small_chars +
numbers + symbols;
// Using random method
Random rndm_method = new Random();
char[] password = new char[len];
for (int i = 0; i < len; i++)
{
// Use of charAt() method : to get character value
// Use of nextInt() as it is scanning the value as int
password[i] =
values.charAt(rndm_method.nextInt(values.length()));
}
return password;
}
}
注意：我们生成的密码每次都会改变。因为我们使用了 random() 方法来生成密码。
输出 ：
Generating password using random() :
Your new password is : KHeCZBTM;-解释OTP（一次性密码）生成的Java程序
// Java code to explain how to generate OTP
// Here we are using random() method of util
// class in Java
import java.util.*;
public class NewClass
{
static char[] OTP(int len)
{
System.out.println("Generating OTP using random() : ");
System.out.print("You OTP is : ");
// Using numeric values
String numbers = "0123456789";
// Using random method
Random rndm_method = new Random();
char[] otp = new char[len];
for (int i = 0; i < len; i++)
{
// Use of charAt() method : to get character value
// Use of nextInt() as it is scanning the value as int
otp[i] =
numbers.charAt(rndm_method.nextInt(numbers.length()));
}
return otp;
}
public static void main(String[] args)
{
int length = 4;
System.out.println(OTP(length));
}
}
笔记 ：
我们生成的 OTP 每次都会改变。因为我们使用了 random() 方法来生成 OTP。
输出 ：
Generating OTP using random() :
You OTP is : 5291方法二：
解释密码生成的Java程序
// Java code to explain how to generate random
// password
class uniquePassword
{
public static long Code() //this code returns the unique 16 digit code
{ //creating a 16 digit code using Math.random function
long code =(long)((Math.random()*9*Math.pow(10,15))+Math.pow(10,15));
return code; //returning the code
}
//method to generate the password
//by converting every two digits as an ascii value of a character
public static void main(String args[])
{
long code=Code();//function calling
String unique_password="";
for (long i=code;i!=0;i/=100)//a loop extracting 2 digits from the code
{
long digit=i%100;//extracting two digits
if (digit<=90)
digit=digit+32;
//converting those two digits(ascii value) to its character value
char ch=(char) digit;
// adding 32 so that our least value be a valid character
unique_password=ch+unique_password;//adding the character to the string
}
System.out.println("unique password ="+unique_password);
}
}
// Here we are using random() method of util
// class in Java
注意：我们生成的密码每次都会改变。因为我们使用了 random() 方法来生成密码。
输出 ：
Generating password using Math.random() and ascii code:
Your new password is : KHe%ZBT$ASCII码表：
解释OTP（一次性密码）生成的Java程序
// Java code to explain how to generate OTP
public class GenerateOTP {
//declaring a of return type String
//which on calling provides the otp
public static String generateOTP()
{ //int randomPin declared to store the otp
//since we using Math.random() hence we have to type cast it int
//because Math.random() returns decimal value
int randomPin =(int) (Math.random()*9000)+1000;
String otp = String.valueOf(randomPin);
return otp; //returning value of otp
}
public static void main(String args[])//method to call and print otp
{
String otpSting =generateOTP();//function calling
System.out.println("OTP : "+otpSting);
}
}// Here we are using Math.random() function.
// class in Java
笔记 ：
我们生成的 OTP 每次都会改变。因为我们已经使用 Math.random()函数来生成 OTP。
输出 ：
Generating OTP using random() :
You OTP is : 5291