refreshing JEditorPane

I need to refresh the content of a JEditor Pane multiple times, I am using the following code for this purpose

Code :

---

java.net.URL Content =  file.toURI().toURL();
		    	if (Content != null) {
					tArea[i].setPage(Content);
					i++;		
					}

---

but it only loads "Content" to my JEditorPane for the first time and it doesn't work properly any more althogh when I check the "Content", it is refreshed.

My guess is the problem lies outside the code you posted. Where are you calling this code: from a loop? In the event dispatching thread?

I call it in a while loop which is in a method as a part of mouse listener class.

this is the loop

Code :

---

 
File file = new File("result.html");
while(r>0 & r<l & e>0){
 
		    	fos = new FileOutputStream(file);
		    	dos = new DataOutputStream(fos);
		    	dos.writeBytes(Results.substring(r, e));
		    	java.net.URL Content =  file.toURI().toURL();
		       	if (Content != null) {
					tArea[i].setPage(Content);
					i++;		
					}
 
		    	r = Results.indexOf("<a href=",e);
		    	e = Results.indexOf("Cached",r);
		    }

---

I am trying to write the content of "result.html" file on myjeditorpane

I solved the problem by clearing the stream description property but now I got this exception

Code :

---

Exception in thread "Thread-14" java.lang.NullPointerException
	at javax.swing.JEditorPane$PageLoader.run(Unknown Source)

---

what is the reason?

I have moved this thread to the correct forum -

AWT / Java Swing - Java Programming Forums

Hello nasi,

Can you please post the full version of your code? We can attempt to compile it and generate the error then..

it is multiple classes, I can't post all of it. the following is the code that generates this thread

Code :

---

while(r>0 & r<l & e>0){
 
		    	dos.writeBytes(Results.substring(r, e));
		    	java.net.URL Content =  file.toURI().toURL();
		    	tArea[i].setPage(Content);
 
				r = Results.indexOf("<a href=",e);
		    	e = Results.indexOf("Cached",r);
		    	i++;
		    }
		    for (int j=0; j<10; j++){
		    	Document doc = tArea[j].getDocument();
		    	doc.putProperty(Document.StreamDescriptionProperty, null);
		    }

---

I need to clear the stream description property to be able to reload my jeditorpane but it causes a NullPointerException.

This is similar to what I am doing and generates nullPointer thread. more over it doesn't write the Content to my JEditorPane (tArea) properly

Code :

---

package test;
 
import java.io.DataOutputStream;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.UnsupportedEncodingException;
import java.net.MalformedURLException;
import java.net.URL;
import java.net.URLConnection;
import java.net.URLEncoder;
 
import javax.swing.JEditorPane;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.text.Document;
 
 
public class test extends JFrame{
	/**
	 * 
	 */
 
	private String query="university" ;
	private String collection = " site:wikipedia.org";
	private String searchEngine = "http://www.google.com";
	private StringBuilder Results = new StringBuilder();
	private JEditorPane[] tArea = new JEditorPane[10];
	private File file ;
	private FileOutputStream fos;
	private DataOutputStream dos;
	private JPanel panel = new JPanel();
 
	public  test(){
 
		for (int y=0;y<10;y++){
			tArea[y]= new JEditorPane();
			panel.add(tArea[y]);
		}
 
		this.add(panel);
		URL url = null;
		try {
			url = new URL(searchEngine + "/search?hl=en&source=hp&q="+  URLEncoder.encode(query + collection, "UTF-8")+ "&meta=&aq=f&aqi=g10&aql=&oq=&gs_rfai=" );
		} catch (MalformedURLException e1) {
			// TODO Auto-generated catch block
			e1.printStackTrace();
		} catch (UnsupportedEncodingException e1) {
			// TODO Auto-generated catch block
			e1.printStackTrace();
		}
	    URLConnection Connection = null;
		try {
			Connection = (URLConnection)url.openConnection();
		} catch (IOException e1) {
			// TODO Auto-generated catch block
			e1.printStackTrace();
		}
	    Connection.setRequestProperty("User-Agent", "Mozilla 5.0");
		    InputStream inputStream = null;
			try {
				inputStream = Connection.getInputStream();
			} catch (IOException e1) {
				// TODO Auto-generated catch block
				e1.printStackTrace();
			}
 
		    int ch=0; 
		    Results.delete(0, Results.length());
 
	    try {
			while ((ch=inputStream.read()) > 0) {
			    	Results.append((char)ch);
			}
		} catch (IOException e1) {
			// TODO Auto-generated catch block
			e1.printStackTrace();
		}
	//    System.out.println(Results);
	   	int l = Results.lastIndexOf("<a href="/ last occurrence of <a href
	    int f = Results.indexOf("Search Results");//beginning of search results
	    int r = Results.indexOf("<a href=",f);//first <a href after f
	    int e = Results.indexOf("Cached",r);//first similar(end of results of one link) after r
	    int i=0;
 
 
	    while(r>0 & r<l & e>0){
	    	file = new File("result.html");
			try {
				fos = new FileOutputStream(file);
			} catch (FileNotFoundException e1) {
				// TODO Auto-generated catch block
				e1.printStackTrace();
			}
			dos = new DataOutputStream(fos);
			try {
				dos.flush();
			} catch (IOException e1) {
				// TODO Auto-generated catch block
				e1.printStackTrace();
			}
			try {
				dos.writeBytes(Results.substring(r, e));
			} catch (IOException e1) {
				// TODO Auto-generated catch block
				e1.printStackTrace();
			}	
			try {
				fos.close();
			} catch (IOException e1) {
				// TODO Auto-generated catch block
				e1.printStackTrace();
			}
		    try {
				dos.close();
			} catch (IOException e1) {
				// TODO Auto-generated catch block
				e1.printStackTrace();
			}
	    	java.net.URL Content = null;
			try {
				Content = file.toURI().toURL();
			} catch (MalformedURLException e1) {
				// TODO Auto-generated catch block
				e1.printStackTrace();
			}
	    	System.out.println(Results.substring(r, e));
	    	try {
				tArea[i].setPage(Content);
			} catch (IOException e1) {
				// TODO Auto-generated catch block
				e1.printStackTrace();
			}
	    	r = Results.indexOf("<a href=",e);
	    	e = Results.indexOf("Cached",r);
	    	i++;
	    	file.delete();
 
	    }
 
	    for (int j=0; j<10; j++){
	    	Document doc = tArea[j].getDocument();
	    	doc.putProperty(Document.StreamDescriptionProperty, null);
	    } 
 
 
 
	}
public static void main(String[] args) {
 
		JFrame frame= new test();
 
		frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		frame.pack();
		frame.setVisible(true);  
}
 
}

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no answer :(