query not work properly every time!

[Mandar Khire]

I create java program with database mysql, connectivity hibernate.
By Java program i handle 90 or 900 or 9000 small Jpanel within Big Jpanel, handle means drag & drop. I save co-ordinates in db table.
I faced many test conditions & solved as many as possible with the help of this forum.
Now i got 3 different ways to do this kind of program.
Scenario:-
Now In this topic,
when in swing program in mousereleased event i call

public void mouseReleased(MouseEvent e) {
JPanel panel=(JPanel)e.getSource();
int x1=panel.getX();
int y1=panel.getY();
int x2=x1+40;
int y2=y1+50;
setLocation1(x1, y1);
getParent().getParent().repaint();
getParent().getParent().getParent().repaint();
getParent().getParent().getParent().getParent().repaint();
}

where setlocation1 is another function which used for send co-ordinates to function which check overlap or not with the help of sql query or set panel at calculated location(this i learn from one my old post in coderanch).

public void setLocation1(int x1, int y1){
if(x1 == 0 && y1 == 0){
x1 = 50;
y1 = 5;
x2=x1+40;
y2=y1+50;
}else{
// y1 = 5;
if(x2 == 0 && y2 == 0){
x2=x1+40;
y2=y1+50;
}
}
overlap_flag=true;
overlap_flag=checkoverlap(x1, y1, x2, y2);
if(overlap_flag==false){
---update in database by java code---
}else{
if(x,y present in data base == yes){
--set location at database x,y by java code---
}else{
---do calculation & set x,y for panel by java code---
}

where checkoverlap function written for call getoverlap fucntion to call sql query, & set flag.

public boolean checkoverlap(int x1,int y1,int x2,int y2){
overlap_flag=false;
overlap=dbintInterface.getoverlap(x1,x2,y1,y2);
if(overlap==null || overlap.size()==0){
overlap_flag=false;
}else{
overlap_flag=true;
}
return overlap_flag;
}

I write SQL query to check overlap of 2 rectangles with the help of Rectangle's 4 co-ordinate.

public List getoverlap(int x1, int x2, int y1, int y2) {
List resultList = null;
Session session = null;
try {
String siteName = Utility.getInstance().getSiteName();
session = HibernateUtil.getSessionFactory(siteName + ".cfg.xml").openSession();
session.beginTransaction();
String selectQuery = "from tablename mytable where ((" +
""+x1+" <= mytable.x1 and "+x2+" >= mytable.x1) and ( "+y1+" <= mytable.y1 and "+y2+">=mytable.y1))" +
" or (("+x1+" <= mytable.x2 and "+x2+" >= mytable.x2) and ("+y1+" <= mytable.y2 and "+y2+">=mytable.y2 ))" +
"or (("+x1+" <= mytable.x3 and "+x2+" >= mytable.x3) and ("+y1+" <= mytable.y3 and "+y2+">=mytable.y3 ))" +
"or (("+x1+" <= mytable.x4 and "+x2+" >= mytable.x4) and ("+y1+" <= mytable.y4 and "+y2+">=mytable.y4 ))" +
" order by mytable.panelno";
System.out.println(selectQuery);
Query q = session.createQuery(selectQuery);
resultList = q.list();
if(resultList!=null)
System.out.println("getoverlap size="+resultList.size()); //this give me how many panels overlaped due to drag panel over them, it should be greater than 0.
session.getTransaction().commit();
} catch (HibernateException he) {
he.printStackTrace();
} finally {
if (session != null) {
if (session.isOpen()) {
session.close();
}
}
}
return resultList;
}

now when i run program with 90 or 900 or 9000 panels, no problem for set all panels at calculated position at first time, in db also panels all co-ordinates save properly.
but when i try to drag panel & mouse released at overlap position on another panel, my above group of functions work fine & set dragged panel its original position means
it avoid overlap, but i do this for 10 times 20 times then it give trouble. overlap_flag should true whenever panel overlap. but it not get true due to something not work properly.
I write print statement which give me result list size, when overlap occurs it give no>0, but i can see in program overlap done but in console i see print statement give 0 means no overlap.
How all above functions work correctly for few times & for few times work wrongly & again work correctly?
Please somebody help me.