java - Getting Null pointer Exception while String comparision -

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i have written simple login module in jsp (a lot of scriplets there :) ). but, continuously getting nullpointer exception error. not able find, tried lot.

jsp login code

<form action="loginaction.jsp" method="post" name="config-form"> <table align="center">     <tr>         <td> username:</td>         <td><input type="text" name="username" required parameter=*"></td>     </tr>     <tr>         <td> password:</td>         <td><input type="password" name="username" required parameter=*"></td>     </tr>     <tr><td><input type="submit" value="login"></td></tr> </table>

loginaction.jsp

<body> <%     string username=request.getparameter("username");     string password=request.getparameter("password");       loginmodel login = new loginmodel();     login.setusername(username);     login.setpassword(password);      loginvalidator validator = new loginvalidator();     boolean validate=validator.validatelogin(login);      if(validate==false)     {         response.sendredirect("login.jsp");     }     else     {         response.sendredirect("index.jsp");     }  %>

loginmodel.java

public class loginmodel { private string username; private string 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; }

}

loginvalidator.java

public boolean validatelogin(loginmodel login) {     string uname="vivekaltruist";     string passwd="somepassword";     system.out.println(login.getusername());     if((login.getusername().equals(uname)) && login.getpassword().equals(passwd))     {         return true;     }         return false; }

the stacktrace:

java.lang.nullpointerexception @ loginvalidator.validatelogin(loginvalidator.java:12)

i sure, silly reason,but not able find it. same thing, tried without jsp, working fine. me out

you've named password input parameter username too

<td><input type="password" name="username" required parameter=*"></td>

this

string password=request.getparameter("password");

will return null because there no request parameter identified password , cause nullpointerexception when try , call equals() on it. change name attribute "password".


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