Using Java arrays to simulate login and registration functions

Package com.linkage.login;

Import Java.util.Scanner;

public class User {
Store user name and password
public static String arr1[] = new STRING[3];
public static String arr2[] = new STRING[3];
static int index = 0;

@SuppressWarnings ("resource")
public static void Main (string[] args) {
Arr1[0] = "Zhangsan";
Arr2[0] = "Zhang";
while (true) {
Print ();
Scanner scan = new Scanner (system.in);
SYSTEM.OUT.PRINTLN ("Please select function:");
String str = Scan.next ();
if (Str.equals ("1")) {
Login ();
} else if (Str.equals ("2")) {
Register ();
} else if (Str.equals ("0")) {
System.exit (0);
Break
} else if (Str.equals ("3")) {
Show ();
} else {
SYSTEM.OUT.PRINTLN ("input error");
}
}
}

Login function
@SuppressWarnings ("resource")
public static void login () {

for (int i = 0; i < 3; i++) {
Scanner scan1 = new Scanner (system.in);
System.out.println ("Please enter user name:");
String str1 = Scan1.next ();
Scanner scan2 = new Scanner (system.in);
System.out.println ("Please enter password:");
String str2 = Scan2.next ();
for (int i1 = 0; i1 < arr2.length; i1++) {
if (Str1.equals (Arr1[i1]) && str2.equals (Arr2[i1])) {
SYSTEM.OUT.PRINTLN ("Login Successful! ");
Return
}
}
SYSTEM.OUT.PRINTLN ("Login failed, please re-enter!") ");
}
}

Registration function
@SuppressWarnings ("resource")
public static void register () {
Scanner scan1 = new Scanner (system.in);
System.out.println ("Please enter user name:");
String str1 = Scan1.next ();
Scanner scan2 = new Scanner (system.in);
System.out.println ("Please enter password:");
String str2 = Scan2.next ();

Boolean flag = false;
for (int i = 0; i < arr1.length; i++) {
if (Str1.equals (Arr1[i])) {
System.out.println ("User name already exists");
Flag = true;
}
}
if (flag = = False) {
index++;
if (Index < arr1.length) {
Arr1[index] = str1;
Arr2[index] = str2;
SYSTEM.OUT.PRINTLN ("Registered successfully! ");
} else {
Add ();
Arr1[index] = str1;
Arr2[index] = str2;
SYSTEM.OUT.PRINTLN ("Registered successfully! ");

}
}
}

Display user Information
public static void Show () {
for (int i = 0; i < arr1.length; i++) {

if (arr1[i]! = null) {
System.out.println ("User name:" + arr1[i] + "," + "Password:" + arr2[i]
+ "\ n");
}
}
}

Increase array length
public static void Add () {
String newarray1[] = new String[arr1.length + 3];
String newarray2[] = new String[arr1.length + 3];
System.arraycopy (arr1, 0, newarray1, 0, arr1.length);
System.arraycopy (arr2, 0, newarray2, 0, arr1.length);
arr1 = Newarray1;
ARR2 = Newarray2;
Show ();
}

Input content
public static void print () {
System.out.println ("--------------------small fat Fish Management System--------------------");
System.out
. println ("1. Login function (login)");
System.out
. println ("2. Registration function (register)");
System.out
. println ("3. View (show)");
System.out
. println ("0. Exit");
System.out.println ("--------------------small fat Fish Management System--------------------");
}
}

Using Java arrays to simulate login and registration functions