How to find out image size (in pixels) of jpg and gif files

Question

this seems to work, though i doubt that it would very time:
               Image img = Toolkit.getDefaultToolkit().getImage("car.jpg");
               int w = img.getWidth(null);
               int h = img.getHeight(null);
               while(w <= 0 || h <= 0)
                  try{Thread.sleep(10);}catch(InterruptedException ix){}
                  w = img.getWidth(null);
                  h = img.getHeight(null);
               JOptionPane.showMessageDialog
                  null,
                  filenames[i] + ": " + w + "x" + h,
                  "ImgSize",
                  JOptionPane.INFORMATION_MESSAGE
               );please suggest a better solution.
thanks

Answer 1

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We've a requirement that we need to find out the size of a java object at run time, is there a direct java API to get the size of a composite object in memory?
Here is my requirement: We are adding string objects (which is an xml string of considerable size) into a List. After reaching certain size limit (lets say 5MB) of the list i need to put this data into DB as a CLOB. So every time I add a string object to the list, I need to see if the total size of the list exceeds the limit and if yes, flush the results into DB.
I am not sure if java has a direct API for this, if not what is the beast way to do it, it s critical requirement for us.
It would be really great if someone could help us out.
>
Could you explain your actual requirement a little more fully.
1. Is each individual string a separate XML string? Or is it just a fragment? Why would you just concatenate them together into a CLOB? That won't produce valid XML and it won't let you easily separate the pieces again later. So provide a simple example showing some strings and how you need to manipulate them.
2. Are you using these xml strings in Java at all? Or are you just loading them into the database?
For example if you are just loading them into the database you don't need to create a list. Just create a CLOB in Java and append each string to the CLOB. Before you append each one you can check to see if the new string will put you over your length limit. If it will then you write the CLOB to the database, empty the CLOB and start appending again to the new clob instance.
If you explain what you are really trying to do we might be able to suggest some better ways to do it.