Write data from Database to File in Java -


i trying write data database text file.

the text file remains empty. tried deg. here code:

public void writetext() {      try     {         class.forname("com.mysql.jdbc.driver");     }     catch(exception e)     {         e.printstacktrace();     }     final string db_url ="jdbc:mysql://mis-sql.uhcl.edu/gattupalliv3940";     connection conn = null;     statement stat  = null;     resultset rs = null;     try     {         conn = drivermanager.getconnection(db_url,"gattupalliv3940","1552688");         stat = conn.createstatement();         rs = stat.executequery("select * student_2");         filewriter fw = new filewriter("data.txt");         bufferedwriter bw = new bufferedwriter(fw);         string line ="";         while(rs.next())         {             line = rs.getint(1)+"\t"+rs.getstring(2)+"\t"+rs.getdouble(3);             bw.write(line);             bw.newline();         }         bw.close();     }     catch(exception e)     {         e.printstacktrace();     }         {         try         {             conn.close();             rs.close();             stat.close();         }         catch(exception e)         {             e.printstacktrace();         }     } }

if aren't getting errors , file empty, thing can happening while(rs.next()) line must returning false first time through; meaning aren't getting database.

have stepped through code verify lines executing , ones not?

i suspect file isn't being written expect since aren't specifying directory. created simple test , file written out tomcat's directory @ ...\springsource\vfabric-tc-server-developer-2.6.4.release\spring-insight-instance\wtpwebapps\junk\data.txt (my project named junk). below code (without database stuff):

@requestmapping(value="/") public modelandview test(httpservletrequest request, httpservletresponse response) throws ioexception{      writetext(request.getrealpath("data.txt"));      return new modelandview("home"); }  public void writetext(string path) {     bufferedwriter bw = null;     try {         filewriter fw = new filewriter(path);         bw = new bufferedwriter(fw);         string line = "this test";         bw.write(line);         bw.newline();     }     catch(exception e) {         e.printstacktrace();     } {         if( bw != null ) {             try {                 bw.close();             } catch (ioexception e) {                 // ignore             }         }     } }

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