How do I create a global login so that when the user logs in with their username and password that information is retained?

Here is my connection class. Currently, I am using static final variables to send the username and password to the connection method.

Code:
/**
 * This is the Connection class 
 */

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;

public class DatabaseConnection {

	static final String JDBC_DRIVER = "com.mysql.jdbc.Driver";
	static final String DATABASE_URL = "jdbc:mysql://localhost:3306/db";
	static String DATABASE_NAME = "db";
	static final String USERNAME = "root";
	static String PASSWORD = "";
	
    	static Connection con;
		public static boolean login; //login flag
    	
    	//***Constructor***
    	public DatabaseConnection( )
    	{
    				
    		try
    		{
    		      Class.forName(JDBC_DRIVER).newInstance();
    		      //connect();
    	    }
    	    catch(Exception e)
    	    {
    	     	e.printStackTrace();
    	    }		
    	}
    	//***end of Constructor***
    	

    	//***connect***
    	//Menu Option 1
    	public static Connection getConnection(String username, String password)
    	{
    				
    		try {
    	Class.forName(JDBC_DRIVER);

    		} catch(java.lang.ClassNotFoundException e) {
    			System.err.print("ClassNotFoundException: ");
    			System.err.println(e.getMessage());
    		}

    		try {
    			con = DriverManager.getConnection(DATABASE_URL, USERNAME, PASSWORD);
    			System.out.println("*** Connected ***");
    			login = true; //login flag

    		} catch(SQLException ex) {
    			System.err.println("SQLException: " + ex.getMessage());
    			System.out.println("*** Incorrect Login Details ***");
        		login = false; //login flag
    		}
  
    		
    		return con;

    	}
    	
    	//Menu Option 9 - Disconnect
    	public void disconnect()
    	 {
    	  if (con != null)
    	    {
    	     try
    	     {
    	      con.close();
    	      System.out.println("You are now disconnected from the Database \n");
    	     }
    	     catch (Exception e) 
    	     {
    	    	 e.printStackTrace(); 
    	     }
    	    }
    	 }//***end of disconnect***


    		
    	}//end of class
Ideally, I want the User to run a query without having to log in all the time.

Code:
   	    public void insertTableCommand () throws SQLException, IOException
	    	{

			    if (c.login == true) //Successful
		        {
		    	
		    	 try
		    	 {
		    	
		    		 Connection con = c.getConnection(c.USERNAME, c.PASSWORD);
		    		 
			    	 // create java preparedstatement using a sql update query
			    	 String sql = "INSERT INTO test (Field1, Field2)" + 
			    	 "VALUES(?,?)";
					 PreparedStatement ps1 = con.prepareStatement(sql);
			    	 BufferedReader bf = new BufferedReader(new InputStreamReader(System.in));

			    	 System.out.println("Enter movie name:");
			    	 //set the preparedstatement parameters
			    	 String Field1 = bf.readLine();
			    	 ps1.setString(1, Field1);

			    	 System.out.println("Enter year:");
			    	 String Field2 = bf.readLine();
			    	 ps1.setString(2, Field2);

					 int count = ps1.executeUpdate(); // call executeUpdate to insert sql insert statement
					 System.out.println("Thank you - table updated.  " + count + " row(s) affected");

					 con.commit();//commit the changes to the DB
					 con.close();//close the statement
					 ps1.close();//close the connection
			    	 
					}
				  catch (SQLException s){
				  System.out.println("SQL statement is not executed!");
				  }
				  catch (Exception e){
				  e.printStackTrace();
				  }
		        }
			    else //Unsuccessful
		    	{
					System.out.println("You are not logged in.  Please select menu item 1 to login");
		    	}
			    
		   }//end of method

Thanks