jdbc - OJDBC code issue in Java Eclipse -

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i have made registration table reg1 , stored values every registered users html file. have made log-in page in html users can give username , see datas entered them. have made user "bbb" , want show username only.so made general java code follows:

    import java.io.ioexception;     import java.io.printwriter;     import java.sql.connection;     import java.sql.drivermanager;     import java.sql.preparedstatement;     import java.sql.resultset;     import java.sql.sqlexception;     import java.sql.statement;      import javax.servlet.servletexception;     import javax.servlet.http.httpservlet;     import javax.servlet.http.httpservletrequest;     import javax.servlet.http.httpservletresponse;      public class check extends httpservlet {     private static final long serialversionuid = 1l;      /**     * @see httpservlet#doget(httpservletrequest request, httpservletresponse response)     */         protected void doget(httpservletrequest request, httpservletresponse response) throws servletexception, ioexception {          // todo auto-generated method stub          string username=request.getparameter("username");          try{              class.forname("oracle.jdbc.driver.oracledriver");              string url="jdbc:oracle:thin:@localhost:1521:xe";              connection con=drivermanager.getconnection(url,"system","root");              statement stmt=con.createstatement();              resultset rs=stmt.executequery("select uname reg1");               while(rs.next())                     {                  string name=rs.getstring("uname");                 if(name==username)                 {                   response.setcontenttype("text/html");                 printwriter pw=response.getwriter();                 pw.println("your user name is:"+username);              //  system.out.println(""+name);                 }                        con.commit();                  }              stmt.close();     }                   catch (sqlexception e) {                     // todo auto-generated catch block                     e.printstacktrace();                 } catch (classnotfoundexception e) {                     // todo auto-generated catch block                     e.printstacktrace();                 }       }     }

it giving errors java.sql.sqlexception: closed statement: next

the table follows:

fname lname addr mail occu uname passwd aaa aaa aaaa aaa aaaa bbb cccc bkgkb jjv jhvjmh jjkg jvjv jvjvh bjbmb

please me resolving this!!

try removing con.commit line, there no need that.

you should add finally catch , close statement there.

and should use preparedstatement instead of statement.

about finally see here.


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