Question

我想将用户名“carl”与密码“0001”以及其他元素匹配，但它不起作用。任何人都可以解释我如何将“用户名”的每个元素与“密码”的元素相匹配？非常感谢你！这是我的代码：

class log{
    BufferedReader br= new BufferedReader(new InputStreamReader(System.in));
    String [] username ={"carl", "may", "joseph", "oliver", "ashley"};
    String []password={"0001", "0002", "0003", "0004", "0005"};

    public void login() throws IOException{
    System.out.print("\nUSERNAME: ");
    uname=br.readLine();
    System.out.print("PASSWORD: ");
    pword=br.readLine();

    for (j = 0; j <= 4; j++) {
         if (username[j].equals(password[j])) {
           uname=username[j];
           pword=password[j];
    }          
}
while((!uname.equals(password[j]))&&(!pword.equals(username[j]))){
    System.out.println("Invalid username/password.");
    System.out.print("\nUSERNAME: ");
    uname=br.readLine();
    System.out.print("PASSWORD: ");
    pword=br.readLine();
}

public void main(String[] args)throws IOException {
       log b=new log();
       b.login();
}

Answer 1

我认为你应该按照以下方式修改你的方法

http://localhost:8084/mavenwebproject/XmlServletForm.html

Answer 2

我认为使用额外的课程User会更好。

该课程如下：

class User {
     private String name;
     private String pw;
     public User (String name, String pw) {
         this.name = name;
         this.pw = pw;
    }
    public String getName() {
        return this.name;
    }
    public String getPw() {
        return this.pw;
    }
}

在您的程序逻辑中，您有一个包含所有用户的列表：

ArrayList<User> userList

现在您已更改登录算法：

class log{
    BufferedReader br= new BufferedReader(new InputStreamReader(System.in));
    ArrayList<User> userList = ...; //Here you have to add all users first

    boolean loginCheck = false;
    while(loginCheck == false) {
        System.out.print("\nUSERNAME: ");
        uname = br.readLine();
        System.out.print("PASSWORD: ");
        pword = br.readLine();
        for (int i = 0; i < userList.size(); i++) {
            if (userList.get(i).getName.equals(uname) && userList.get(i).getPw.equals(pword)) {
                loginCheck = true;
                break;
            }
        }

    }            
}    

public void main(String[] args)throws IOException {
       log b=new log();
       b.login();
}

如果将用户输入的检查更改为：

，则可以使算法更快

for (int i = 0; i < userList.size(); i++) {
            if (userList.get(i).getName.equals(uname)) {
                if (userList.get(i).getPw.equals(pword)) {
                    loginCheck = true;
                    break;
                } else {
                    break;
                }                
            }
}

Answer 3

您可以使用OOP（面向对象编程）来更轻松地解决您的问题：

以下是我的示例解决方案：

用户类：

class User {

private String username;
private String password;

public User(String username, String password) {
    this.username = username;
    this.password = password;
}

public String getUsername() {
    return username;
}

public void setUsername(String username) {
    this.username = username;
}

public String getPassword() {
    return password;
}

public void setPassword(String password) {
    this.password = password;
}

@Override
public boolean equals(Object o) {
    User user2 = (User) o;
    if (this.username.equals(user2.getUsername()) && this.password.equals(user2.getPassword()))
        return true;

    return false;
}

}

登录课程：

public class Login {


private User[] users = new User[]{
        new User("carl", "0001"),
        new User("may", "0002"),
        new User("joseph", "0003"),
        new User("oliver", "0004"),
        new User("ashley", "0005"),
};


public static void main(String args[]) throws IOException {
    BufferedReader br = new BufferedReader(new InputStreamReader(System.in));

    System.out.print("\nUSERNAME: ");
    String uname = br.readLine();
    System.out.print("PASSWORD: ");
    String pword = br.readLine();


    boolean success = new Login().login(new User(uname, pword));
    if (success)
        System.out.println("The user account is valid, login");
    else
        System.out.println("The username and/or password is invalid.");


}

public boolean login(User user) {
    for (int i = 0; i < users.length; i++) {
        if (users[i].equals(user))
            return true;
    }

    return false;
}

}

匹配java中用户名和密码索引的索引

3 个答案: