NetBeans Tomcat Jsp mysql forms login and session

[Se Koan]

I have a NetBeans web project on Tomcat 8.0.15, MySql (with Jconnector), Servlet/Jsp. I need a secure login!!!

There is a login page. On successful login, if it is admin, servlet redirects to the admin page, if username is of a standardUser, the servlet redirects to the main page.

For now nothing works. The page is not redirected by servlet, on submit button press the error.html appears and shows response.getStatus() is 0!!! I tested(without login) servlet for username/password check against the DB and it works.

so Here is my code files: login.jsp:

<form id="loginForm" method="POST" action="j_security_check">
                        <input name="j_username" id="j_username" type="email" value="[e-mail]"></input>
                        <input name="j_password" id="j_password" type="password" value="test"></input>
                        <input id="loginSubmit" type="submit" value="Login"></input></form>

web.xml:

 <servlet>
        <servlet-name>LoginServlet</servlet-name>
        <servlet-class>ViViDSpectraDC.AuthServlet</servlet-class>
    </servlet>
    <servlet-mapping>
        <servlet-name>LoginServlet</servlet-name>
        <url-pattern>/j_servlet_check</url-pattern>
    </servlet-mapping>
<session-config>
        <session-timeout>
            30
        </session-timeout>
    </session-config>
    <welcome-file-list>
        <welcome-file>Login.jsp</welcome-file>
        <welcome-file>index.html</welcome-file>
    </welcome-file-list>
    <login-config>
        <auth-method>FORM</auth-method>
        <realm-name>MyDatabase</realm-name>
        <form-login-config>
            <form-login-page>/Login.jsp</form-login-page>
            <form-error-page>/Error.html</form-error-page>
        </form-login-config>
    </login-config>
    <security-role>
        <description>Web Site Administrator</description>
        <role-name>admin</role-name>
    </security-role>
    <security-role>
        <description>Stansard user</description>
        <role-name>user</role-name>
    </security-role>
    <security-constraint>
        <web-resource-collection>
           <web-resource-name>ViViDSpectraDC</web-resource-name>
           <url-pattern>/adminpages/*</url-pattern>
           <url-pattern>/userpages/*</url-pattern>
           <http-method>POST</http-method>
        </web-resource-collection>
        <auth-constraint>
           <role-name>admin</role-name>
        </auth-constraint>
    </security-constraint>
    <security-constraint>
        <web-resource-collection>
           <web-resource-name>ViViDSpectraDC</web-resource-name>
           <url-pattern>/userpages/*</url-pattern>
           <http-method>POST</http-method>
        </web-resource-collection>
        <auth-constraint>
           <role-name>user</role-name>
        </auth-constraint>
    </security-constraint>
    <resource-ref>
        <description>DB Connection</description>
        <res-ref-name>MyDatabase</res-ref-name>
        <res-type>javax.sql.DataSource</res-type>
        <res-auth>Container</res-auth>
    </resource-ref>
</web-app> <servlet>
        <servlet-name>LoginServlet</servlet-name>
        <servlet-class>ProjectP.Auth</servlet-class>
    </servlet>
    <servlet-mapping>
        <servlet-name>LoginServlet</servlet-name>
        <url-pattern>/j_servlet_check</url-pattern>
    </servlet-mapping>
<session-config>
        <session-timeout>
            30
        </session-timeout>
    </session-config>
    <welcome-file-list>
        <welcome-file>Login.jsp</welcome-file>
        <welcome-file>index.html</welcome-file>
    </welcome-file-list>
    <login-config>
        <auth-method>FORM</auth-method>
        <realm-name>MyDatabase</realm-name>
        <form-login-config>
            <form-login-page>/Login.jsp</form-login-page>
            <form-error-page>/Error.html</form-error-page>
        </form-login-config>
    </login-config>
    <security-role>
        <description>Web Site Administrator</description>
        <role-name>admin</role-name>
    </security-role>
    <security-role>
        <description>Stansard user</description>
        <role-name>user</role-name>
    </security-role>
    <security-constraint>
        <web-resource-collection>
           <web-resource-name>ProjectP</web-resource-name>
           <url-pattern>/adminpages/*</url-pattern>
           <url-pattern>/userpages/*</url-pattern>
           <http-method>POST</http-method>
        </web-resource-collection>
        <auth-constraint>
           <role-name>admin</role-name>
        </auth-constraint>
    </security-constraint>
    <security-constraint>
        <web-resource-collection>
           <web-resource-name>ProjectP</web-resource-name>
           <url-pattern>/userpages/*</url-pattern>
           <http-method>POST</http-method>
        </web-resource-collection>
        <auth-constraint>
           <role-name>user</role-name>
        </auth-constraint>
    </security-constraint>
    <resource-ref>
        <description>DB Connection</description>
        <res-ref-name>MyDatabase</res-ref-name>
        <res-type>javax.sql.DataSource</res-type>
        <res-auth>Container</res-auth>
    </resource-ref>
</web-app>

Context.xml:

<Context antiJARLocking="true" path="/ProjectP" allowCasualMultipartParsing="true" >
    <Realm className="org.apache.catalina.realm.JDBCRealm" driverName="com.mysql.jdbc.Driver"
               name="MyDatabase" type="javax.sql.DataSource"
               connectionURL="jdbc:mysql://localhost:3306/mydatabase" 
                   connectionName="root" connectionPassword="sa" 
                   userTable="administrators" userNameCol="username" userCredCol="password"
                   userRoleTable="userroles" roleNameCol="role"
                   auth="Container" maxTotal="100" maxIdle="30" maxWaitMillis="10000"/>  
</Context>

Login.java:

@WebServlet("/j_servlet_check/*")
@MultipartConfig
public class LoginServlet extends HttpServlet {
protected void doPost(HttpS .......
response.setContentType("text/html;charset=UTF-8"); //text/plain
if (checkLoginUser(request.getParameter("j_username"), password)) { //it works for sure, tested...
request.getSession().setAttribute( "username", username );
request.getRequestDispatcher("../admin/Administration.jsp").forward(request, response);

Is context.xml - realm needed?
Why error.html appears and shows response.getStatus() is 0?
So, how to create a secure login?
How j_security_check connects to my MySql database!? - maybe that' the problem error page shows after login...?

[Se Koan]

In context.xml

<?xml version="1.0" encoding="UTF-8"?> <Context antiJARLocking="true" path="/myDBname" allowCasualMultipartParsing="true" > <Realm className="org.apache.catalina.realm.CombinedRealm" > <Realm className="org.apache.catalina.realm.JDBCRealm" driverName="com.mysql.jdbc.Driver" name="myDBname" type="javax.sql.DataSource" connectionURL="jdbc:mysql://localhost:3306/mydbname" connectionName="root" connectionPassword="sasa" userTable="administrators" userNameCol="Email" userCredCol="Password" userRoleTable="administrators" roleNameCol="LoginRole" auth="Container" maxTotal="100" maxIdle="30" maxWaitMillis="10000"/> </Realm> </Context>

web.xml
<resource-ref> <description>DB Connection</description> <res-ref-name>myDBname</res-ref-name> <res-type>javax.sql.DataSource</res-type> <res-auth>Container</res-auth> </resource-ref> <login-config> <auth-method>FORM</auth-method> <realm-name>myDBname</realm-name> <form-login-config> <form-login-page>/pages/Login.jsp</form-login-page> <form-error-page>/pages/Error.jsp</form-error-page> </form-login-config> </login-config> <security-role> <description>Administrator</description> <role-name>admin</role-name> </security-role> <security-constraint> <web-resource-collection> <web-resource-name>myDBname</web-resource-name> <url-pattern>/pages/admin/*</url-pattern> <http-method>POST</http-method> <http-method>GET</http-method> <http-method>PUT</http-method> </web-resource-collection> <auth-constraint> <role-name>admin</role-name> </auth-constraint> </security-constraint> <welcome-file-list> <welcome-file>pages/home.jsp</welcome-file> </welcome-file-list>

Copied mysql-connector-java-5.1.23-bin.jar into C:\Program Files\Apache Software Foundation\Apache Tomcat 8.0.15\lib

I also use <%= request.getContextPath() %> in order to connect resources to pages

<link href="<%= request.getContextPath() %>/resources/styles/main.css" rel="stylesheet" type="text/css"/>