java - Will this cause memory leak? -

will code causes memory leak?

when garbage collector activated? when timer finishes? or gc called though timer still running?

public static swingworker sw;  t2 = new timer (300,this);      t2.start();  @override public void actionperformed(actionevent arg0) { try {     sw = new textareamainpanelworker();     sw.execute(); } catch (throwable e) {     e.printstacktrace(); }    } 

textareamainpanelworker class:

public class textareamainpanelworker extends swingworker<integer, integer> {  protected integer doinbackground() throws exception {     connectmysql.fetchmessage(mainpanel.jtep,mainpanel.sd,mainpanel.count);     return 1; }  protected void done() {     try     {         connectmysql.rodolfol(mainpanel.jtep, mainpanel.sd);     }     catch (exception e)     {         e.printstacktrace();     } } 

method query database:

public static void fetchmessage(jtextpane jtep,styleddocument sd,int count  ) {     try{      string query = "select members.username, message,color chat join members on chat.user_id = members.id message_id > "+count+" , user_id != 1";     ps = con.preparestatement(query);     rs = ps.executequery();     }catch(exception e){} }  public static void rodolfol(jtextpane jtep,styleddocument sd){     try {         while(rs.next())         {             try {                 final jlabel jp = new jlabel(rs.getstring("username")+ "\n");                 jp.setalignmenty(0.75f);                 final string usernamechat = rs.getstring("username");                 jp.addmouselistener(new mouselistener(){                      @override                     public void mouseclicked(mouseevent e) {}                      @override                     public void mouseentered(mouseevent e) {                         cursor c = cursor.getpredefinedcursor(cursor.hand_cursor);                         jp.setcursor(c);                     }                      @override                     public void mouseexited(mouseevent e) {                     }                      @override                     public void mousepressed(mouseevent e) {                         if(swingutilities.isrightmousebutton(e)){system.out.print("lawl");}                         if(e.getclickcount() == 2)new onetoonechat(usernamechat);                          jp.setforeground(color.blue);                     }                      @override                     public void mousereleased(mouseevent e) {                     jp.setforeground(color.black);                     }                 });                 jp.setfont(new font("arial",font.bold,16));                 jtep.insertcomponent(jp);                 styleconstants.setforeground(mainpanel.sas2, color.black);                 mainpanel.sd.insertstring(mainpanel.sd.getlength(), ": ", mainpanel.sas2);                 styleconstants.setforeground(mainpanel.sas,new color(integer.parseint(rs.getstring("color"))));                 sd.insertstring(sd.getlength(),rs.getstring("message")+ "\n", mainpanel.sas);              } catch (badlocationexception e1) {             }finally{             }             mainpanel.count++;}     } catch (sqlexception e) {     }finally{     if (rs != null) {             try {                 rs.close();             } catch (sqlexception sqlex) { }              rs = null;         }      if (ps != null) {             try {                 ps.close();             } catch (sqlexception sqlex) { }              ps = null;         }     } } 

when garbage collector activated? when timer finishes? or gc called though timer still running?

garbage collections happen @ time, feels like. generally, when application running low on memory. gc may run when timer still running putting application on pause (with parallel/throughput collector).

so have no control on when , gc kick in. may happen @ time, regardless of doing in code.