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Permission + Policy File + Java Applet

844235Sep 10 2011 — edited Sep 12 2011

Hi everyone,

I developped a small Java applet for testing purposes.
The aim of the applet is getting data from a MySql database and displayed it into a JLabel.
I use a MySql jdbc layer contained in a Jar file.

I tested the applet locally via Eclipse and it works fine.
Then, I packaged my ".class" files into a Jar file.
I uploaded the resulting Jar file to the server as well as the jdbc Jar file.

I tried to launch the applet located on the server from my web browser (IE9).
An error occured.
I analysed the results in the Java console.
The reason of the problem follows :
I miss a permission grant in my policy file.
The missing line is : permission java.util.PropertyPermission "file.encoding", "read";

For information, the policy file is located at : jre7|lib|security

I do no want to ask the users of my future applet to modify their policy file.
So, I am wondering if there is a way to consider a custom policy file when executing a Java applet.
The custom policy file would be located on the same server as the applet is.

Thanks in advance for your help.

This post has been answered by DrClap on Sep 12 2011

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843804

There is already a topic on this subject
http://forum.java.sun.com/thread.jsp?forum=57&thread=563889

Denis Krukovsky
http://dotuseful.sourceforge.net/

843804

I can't handel this classes. I didn't find out how to use them. Is there any other, maybe easier way to sort TreeNodes?

843804

Thanks for your feedback. What you need to do is
- create a Comparator for your nodes (I believe you know what it is?) or subclass org.dotuseful.ui.tree.SortedTreeNode and implement Comparable interface in it;
- substitute your TreeModel with org.dotuseful.ui.tree.AutomatedTreeModel;
- substitute your tree nodes with org.dotuseful.ui.tree.SortedTreeNode or its subclass, and optionally provide a Comparator for them.

Here is a sketch of a node class that you need

import org.dotuseful.ui.tree;
public class ABSortTreeNode extends SortedTreeNode implements Comparable
    public int compareTo(Object o) {
        MutableTreeNode node = (MutableTreeNode)o;
        return ((Comparable)getUserObject()).compareTo(node.getUserObject());
    }
}

So having this class, you only need to
- substitute your TreeModel with org.dotuseful.ui.tree.AutomatedTreeModel;
- substitute your tree nodes with ABSortTreeNode.

I believe this is pretty easy way to sort a tree. I would make my classes understandable for everyone, so please keep asking questions.

Denis Krukovsky
http://dotuseful.sourceforge.net/

843804

Hi,
The jtree nodes are sorted in jtree display.
But how to keep folders (non-leaf-nodes) and leaf-nodes sorted separately?
I�d like to have the leaf-nodes listed first under root and then all folders followed.
Any ideas? Do you have any samples related that?
Thank you for your help in advance.

843804

Hi,

Thank you for interest in dotuseful library. Good to have people who use our work.

I'm going to write an article about directory tree creation. Stay tuned on http://dotuseful.sourceforge.net/

For this time, what you need is to modify your Comparator or compareTo() method so your folders stay before your files.

Denis Krukovsky
http://dotuseful.sourceforge.net/

843805

This is not exactly what you are looking for but might give you an idea.

Hamed

/**
	 * @param root of tree
	 * @return sorted elements alphabetically
	 */
	public static DefaultMutableTreeNode sortTree(DefaultMutableTreeNode root) {
		for (int i = 0; i < root.getChildCount(); i++) {
			DefaultMutableTreeNode node = (DefaultMutableTreeNode) root
					.getChildAt(i);
			String nt = node.getUserObject().toString();
			for (int j=0; j<i; j++) {
				DefaultMutableTreeNode prevNode = (DefaultMutableTreeNode) root
				.getChildAt(j);
				String np = prevNode.getUserObject().toString();
				if (nt.compareToIgnoreCase(np)<0) {
					root.insert(node, j);
					root.insert(prevNode, i);
				}
			}
			if (node.getChildCount() > 0) {
				node = sortTree(node);
			}
		}
		return root;
	}

843805

This is not exactly what you are looking for but might give you an idea.

Thanks a lot for your code. It helped very much

843806

Thanks Hamed,

Well, I work in your code, and I post here.

  public static DefaultMutableTreeNode sortTree(DefaultMutableTreeNode root) {
        {
                 for (int i =0; i<root.getChildCount()-1; i++) {
                		DefaultMutableTreeNode node = (DefaultMutableTreeNode) root.getChildAt(i);
                        String nt = node.getUserObject().toString();

                        for (int j=i+1;j<=root.getChildCount()-1;j++)
                        {
                            	DefaultMutableTreeNode prevNode = (DefaultMutableTreeNode) root.getChildAt(j);
				                String np = prevNode.getUserObject().toString();

                            System.out.println(nt+" "+np);
                            if (nt.compareToIgnoreCase(np)>0) {

				                  	root.insert(node, j);
					                root.insert(prevNode, i);
				              }
                        }
                        if (node.getChildCount() > 0) {
				node = sortTree(node);
			}
                 }

                 return root;
        }
    }

and this code I used after include in jtree

  public  void jTreeSortingBegin()
    {
          dn = (DefaultMutableTreeNode)treeModel.getRoot();
          treeModel.reload();
          dn = sortTree(dn);
          treeModel.reload(dn);
    }

for exemple

  addObject(jTextField1.getText());
        jTreeSortingBegin();

843806

Thank you very much, Hamed, I only had to change your code a little, replacing

root.insert(prevNode, i);

with

break;

insert(prevNode) is not necessary as insert(node) will shift the rest of the nodes. Break is necessary to begin relocating the next child (in that case we'll be done with that one).

Edited by: Victor.E on May 27, 2009 2:38 AM

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#applet, #connection, #java-applet-development, #mysql, #server

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Java SE (Java Platform, Standard Edition)

Permission + Policy File + Java Applet

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