java - multithreading and JDBC -

i use java , oracle , want use 2 threads read records result set : first thread retrieve records , second read these records.but code obtained first record idea please?

    public class javaapplication13 {    public static  volatile boolean finished =false; public static void main(string[] args) throws ioexception, interruptedexception {       final pipedwriter writer=new pipedwriter();     final pipedreader reader = new pipedreader();     reader.connect(writer);      //thread2: afficher        final thread thread2=new thread("lire")     {         public void run(){             try{                 while(!finished)                 {                    int l=reader.read();                     system.out.println(l);                  }             }catch (exception e) {                  e.printstacktrace();}         }     };        //thread1:récupére de la base    final thread thread1=new thread("db"){         public void run(){             try{     class.forname("com.mysql.jdbc.driver"); connection conn=drivermanager.getconnection("jdbc:mysql://localhost:3306/stage","root", ""); statement s=conn.createstatement();      string sql = "select idetudiant etudiant"; resultset rs=s.executequery(sql);                while(rs.next()){             int k= rs.getint("idetudiant");              writer.write(k);              }                finished=true;             } catch (exception e) {                  e.printstacktrace();             }           }     };     thread2.start();    thread1.start();    thread2.join();    } 

}

there buffer between 2 threads; feature of pipes.

so happens thread1 puts lot of data pipe's buffer , sets finished true.

when enough data in pipe, thread2 start. @ time, finished true, thread read first item , quit.

solution: rid of variable. flush , close pipe writer in thread1 when it's done:

final thread thread1=new thread("db"){     public void run(){         try{             ...         } catch (exception e) {             e.printstacktrace();         }          writer.close(); // send eof other thread     } }; 

in thread2, read pipe reader until read() returns eof (-1):

final thread thread2=new thread("lire") {     public void run(){         try{             while(true)             {                  int l=reader.read();                 if(-1 == l) break; // eof                 system.out.println(l);              }         }catch (exception e) {              e.printstacktrace();}     } };