java - using map interface object to execute a query -

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i have following code me before making changes:

connection connremote = drivermanager.getconnection("jdbc:mysql://11.11.1.111:3306/test",mainuser,mainpass); string maindbsql = null; maindbsql = "select ip_vch table1 table_dt = 1";  // example have following values ip_vch 11.11.11.111,22.22.22.222,33.33.33.333 map<string,connection> connections = new hashmap<>(); devicestmt = connremote.createstatement(); devicers = devicestmt.executequery(maindbsql);  while(devicers.next()){  try{    final string ip_address = devicers.getstring("ip_vch");   system.out.println("value of ip_vch field:"+ip_address);   connections.put(ip_address,drivermanager.getconnection("jdbc:mysql://" + ip_address + ":3306/test",remoteuser,remotepass));   system.out.println("connection "+ip_address+" successfull");  }  catch(sqlexception ex1){   system.out.println(" inner while loop stack trace below:");   ex1.printstacktrace();  } }//end of devicers.next() while loop

now, want put check using sql query follows:

loadchecksql = "select count(*) table2";

however, if consider following code(slightly different above):

connection connremote = drivermanager.getconnection("jdbc:mysql://11.11.1.111:3306/test",mainuser,mainpass); string maindbsql = null; maindbsql = "select ip_vch table1 table_dt = 1";  loadchecksql = "select count(*) table2";// table2 exists in ip address in `ip_vch` field // example have following values ip_vch 11.11.11.111,22.22.22.222,33.33.33.333 map<string,connection> connections = new hashmap<>(); devicestmt = connremote.createstatement(); devicers = devicestmt.executequery(maindbsql);  while(devicers.next()){  try{    final string ip_address = devicers.getstring("ip_vch");   system.out.println("value of ip_vch field:"+ip_address);   connections.put(ip_address,drivermanager.getconnection("jdbc:mysql://" + ip_address + ":3306/test",remoteuser,remotepass));   system.out.println("connection "+ip_address+" successfull");  }  catch(sqlexception ex1){   system.out.println(" inner while loop stack trace below:");   ex1.printstacktrace();  } }//end of devicers.next() while loop

but connections object of map interface , hence wondering how can make loadchecksql work since have following can't use connections below in place of connremote:

loadcheckstmt = connremote.createstatement(); loadcheckrs = loadcheckstmt.executequery(loadchecksql);

i thinking put above 2 lines below following line in above code:

connections.put(ip_address,drivermanager.getconnection("jdbc:mysql://" + ip_address + ":3306/test",remoteuser,remotepass));

please advise


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