Highlighting Text in JTextPane is SUPER SLOW!!

[Yohan Weerasinghe]

Hello all,

Please have a look at the following code. In there, I have made the code small as much as I can.

Form.java

package Normal;

import Keywords.JavaKeywords;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.FlowLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.io.*;
import java.util.ArrayList;
import java.util.List;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.swing.*;
import javax.swing.text.*;


public class Form extends JFrame
{
    private JTextPane textPane;
    private JPanel center,south, north;
    private FlowLayout flow;
    private JScrollPane scroll;
    private List<String> keywords, literals, others;

    
    private String  content;
    public String documentType;
    
    private Style style, style2, style3;
    
    private KeywordConnector java, html, sql, vb;
    
    private DefaultStyledDocument document;
    
   File location = null;
   
    
    private JButton button;
    
    public Form()
    {
        
        //Declaring the instance variables
        textPane = new JTextPane();
        textPane.setMinimumSize(new Dimension(100,100));
        
        button = new JButton("Save");
        button.addActionListener(new Action());
        
        document = (DefaultStyledDocument) textPane.getDocument();  
        document.setDocumentFilter(new HighlightFilter());
        
        keywords = new ArrayList(); 
        literals = new ArrayList();
        others = new ArrayList();

        documentType = ".txt";
                
        //Adding Styles
        style = document.addStyle("blue", null);  
        StyleConstants.setForeground(style, Color.BLUE);
        StyleConstants.setBold(style, true);
        
        style2 = document.addStyle("red", null);
        StyleConstants.setForeground(style2, Color.RED);
        StyleConstants.setBold(style2, true);
        
        style3 = document.addStyle("cyan", null);
        StyleConstants.setForeground(style3, Color.CYAN);
        StyleConstants.setBold(style3, true);
        
        
        
        //Creating the main window
        north = new JPanel();
        north.setLayout(new FlowLayout(FlowLayout.LEFT));
      
        
        center = new JPanel();
        flow = new FlowLayout();
        
        center.setLayout(flow);
        center.add(textPane);
        
        south = new JPanel();
        south.setLayout(new FlowLayout());
        south.add(button);
       
        
        scroll = new JScrollPane(textPane);
        
        getContentPane().add(north,"North");
        getContentPane().add(scroll,"Center");
        getContentPane().add(south,"South");
                
    }

    
    private class HighlightFilter extends DocumentFilter 
    {  
  
    @Override  
    public void insertString(FilterBypass fb, int offset, String string, AttributeSet attr)  
            throws BadLocationException {  
      if (string.isEmpty()) {  
        fb.insertString(offset, string, attr);  
      } else {  
        super.insertString(fb, offset, string, attr);  
        highlight();  
      }  
    }  
  
    @Override  
    public void remove(FilterBypass fb, int offset, int length)  
            throws BadLocationException {  
      if (length == 0) {  
        fb.remove(offset, length);  
      } else {  
        super.remove(fb, offset, length);  
        highlight();  
      }  
    }  
  
    @Override  
    public void replace(FilterBypass fb, int offset, int length, String text, AttributeSet attrs)  
            throws BadLocationException {  
      if (length == 0 && text.isEmpty()) {  
        fb.replace(offset, length, text, attrs);  
      } else {  
        super.replace(fb, offset, length, text, attrs);  
        highlight();  
      }  
    }  
    }
    
    private void highlight() 
    {  
          SwingUtilities.invokeLater(new Runnable() 
          {  
      
            @Override  
            public void run() {  
              try {  
                  
                if(documentType.endsWith(".sql"))
                {
                    content = document.getText(0, document.getLength()).toUpperCase();
                }
                else if(documentType.endsWith(".vb"))
                {
                    content = document.getText(0, document.getLength()).toLowerCase();
                }
                else
                {
                    content = document.getText(0, document.getLength());  
                }
                    int next = 0;  
                    for (String word : content.split("\\s")) {  
                    next = content.indexOf(word, next);  
                    int end = next + word.length();  
                  
                    if(documentType.endsWith(".java"))
                    {
                    document.setCharacterAttributes(next, end,  
                            textPane.getStyle(keywords.contains(word) ? "blue" : literals.contains(word)? "red":"default"),  
                            true);  
                    }
                    else if(documentType.endsWith(".sql"))
                    {
                        document.setCharacterAttributes(next, end,  
                            textPane.getStyle(keywords.contains(word) ? "blue" : "default"),  
                            true);
                    }
                    else if(documentType.endsWith(".vb"))
                    {
                        document.setCharacterAttributes(next, end,  
                            textPane.getStyle(keywords.contains(word) ? "blue" : literals.contains(word)? "red": others.contains(word)? "cyan":"default"),  
                            true);
                    }
                  
                 
                    next = end;  
                }  
              } catch (BadLocationException ex) {  
                ex.printStackTrace();  
              }  
            }  
          });  
        }
    
    public void saveFile() throws BadLocationException
    {
        String content = document.getText(0, document.getLength());
        System.out.println(content);
                
        JFileChooser fileChooser = new JFileChooser();
        fileChooser.setFileSelectionMode(JFileChooser.DIRECTORIES_ONLY);
        
        
        File folder = null;
        
        
        BufferedReader br = null;
        FileWriter fw = null;
        BufferedWriter bw = null;
        
        int returnValue = fileChooser.showSaveDialog(this);
        fileChooser.approveSelection();
        
        if(returnValue == JFileChooser.APPROVE_OPTION)
        {
            try
            {
                folder = fileChooser.getSelectedFile();
            
                location = new File(folder.getAbsolutePath());
                location.createNewFile();
            
            
                
                String data = "";
            
                br = new BufferedReader(new StringReader(content));
                fw = new FileWriter(location);
                bw = new BufferedWriter(fw);
            
                while((data = br.readLine())!=null)
                {
                    System.out.println(data);
                    bw.append(data);
                    bw.newLine();
                }
                bw.flush();
                bw.close();               
                documentType = fileChooser.getDescription(location);
                System.out.println(documentType);
                }
            catch(Exception e)
            {
                e.printStackTrace();
            }
            
            JOptionPane.showMessageDialog(null, "File Saved");
        }
        
        if(documentType.endsWith(".java"))
        {
            java = new JavaKeywords();        
            keywords = java.getKeywords();
            literals = java.getLiterals();
            highlight();
            System.out.println("Java File");
        }
        
                
    }
    
    private class Action implements ActionListener
    {
        public void actionPerformed(ActionEvent ae)
        {
            try {
                saveFile();
            } catch (BadLocationException ex) {
                Logger.getLogger(Form.class.getName()).log(Level.SEVERE, null, ex);
            }
        }
    }
   
   public static void main(String[] args) throws Exception { 
       try
            {
                UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
            }
            catch(Exception e)
            {
                JOptionPane.showMessageDialog(null, e);
            }
        SwingUtilities.invokeLater(new Runnable() 
        {  
            
            Form f;
          @Override  
          public void run() {  
           f = new Form();
           f.setVisible(true);
           f.setSize(800,600);
           f.setLocationRelativeTo(null);
           f.validate();
           f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
          }  
        });  
      } 
}

KeywordConnector.java

package Normal;
import java.util.List;

public interface KeywordConnector
{
    public List<String> getKeywords();
    public List<String> getLiterals();
    public List<String> getOthers();
}

JavaKeywords.java

package Keywords;

import Normal.KeywordConnector;
import java.util.ArrayList;
import java.util.List;
import keywords.Literals;

public class JavaKeywords implements KeywordConnector 
{
    private ArrayList list, literals;
    
    public JavaKeywords()
    {
        //Default Keywords
        list = new ArrayList();
        
        list.add("abstract");
        list.add("assert");        
        list.add("break");
        list.add("byte");
        list.add("case");
        list.add("catch");
        list.add("char");
        list.add("class");
        list.add("continue");
        list.add("default");
        list.add("do");
        list.add("double");
        list.add("else");
        list.add("enum");
        list.add("extends");
        list.add("final");
        list.add("finally");
        list.add("float");
        list.add("for");
        list.add("if");
        list.add("implements");
        list.add("import");
        list.add("instanceof");        
        list.add("interface");
        list.add("long");
        list.add("main");
        list.add("native");
        list.add("new");
        list.add("package");
        list.add("private");
        list.add("protected");
        list.add("public");
        list.add("return");
        list.add("short");
        list.add("static");
        list.add("strictfp");
        list.add("super");
        list.add("switch");
        list.add("synchronized");
        list.add("this");
        list.add("throw");
        list.add("throws");
        list.add("transient");
        list.add("try");
        list.add("void");
        list.add("volatile");
        list.add("while");
        
        //Literals
        String string = "String";
        
        literals = new ArrayList();
        literals.add(string);
        literals.add("bool");
        literals.add("int");
        literals.add("Double");
        literals.add("float");
        literals.add("char");
        literals.add("long");
        literals.add("byte");
        
    }

   
    @Override
    public ArrayList getKeywords()
    {
        return list;
    }

    @Override
    public List<String> getLiterals() 
    {
        return literals;
    }

    @Override
    public List getOthers() {
        throw new UnsupportedOperationException("Not supported yet.");
    }
    
}

Here, what happens is, when the user save the file as ".java", it starts highlighting the java keywords entered by the user.

But, do the following..

1.Copy and paste a code which is really big, something like 300 lines.
2.Save as .java

Now it will become slow, it takes some times to highlight the code. After that, type some keywords, you wont even be able to type, because it gets stuck. This only happens when the code is too big.

Please help me to get rid of this issue. Thanks

[Darryl Burke]

With a quick glance through your code, this jumps out as being woefully inefficient:

for (String word : content.split("\\s")) { 

First off, it's creating a large number of String objects which shortly become eligible for GC; then, it splits on a single whitespace rather than multiple whitespace with multiline (see the docs for java.util.regex.Pattern and/or a regex tutorial).

Take a look at the methods of javax.swing.text.Utilities; I would expect that using those methods in conjunction with Document#getText(...) would be more efficient than your present approach. But you also need to rethink your design to examine only the part of the Document that has been changed -- probably in the DocumentFilter. Examining the entire text is always going to be slow for large files.

[Yohan Weerasinghe]

Thanks for the reply. I really appreciate it.

Take a look at the methods of javax.swing.text.Utilities; I would expect that using those methods in conjunction with Document#getText(...) would be more efficient than your present approach

You mean we have to find the LAST word, INSERTED OR EDITED? I think that is a very good idea!! I worked on it, but I couldn't get the last word. How can I get it? Please help..

[Yohan Weerasinghe]

I tried to access the current row and the edited word, but it didn't work using the methods in Utilities, but it didn't work. Please help..

[Darryl Burke]

If you can make an SSCCE that shows the specific problem and does nothing else, I might take a look. Provided that can be done in a short enough code.

[Yohan Weerasinghe]

Darryl Burke wrote:If you can make an SSCCE that shows the specific problem and does nothing else, I might take a look. Provided that can be done in a short enough code.

Thanks a lot for the reply. OK, I have omitted most of my code, and reduced it to 163 lines. From line 123-126, you will see my failed attempt, in COMMENTS. Here is the code, it is changed, but it still uses the other class and interface which I have posted above, Below is my edited "Form.java" code.

package Normal;  
      
import Keywords.JavaKeywords;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.FlowLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.ArrayList;
import java.util.List;
import javax.swing.*;
import javax.swing.text.*;
      
    public class Form extends JEditorPane  
    {  
        private JTextPane textPane;  
        private JPanel south;
        private JScrollPane scroll;  
        private List<String> keywords, literals; 
        private String  content;  
        public String documentType;            
        private Style style, style2;           
        private KeywordConnector java;           
        private DefaultStyledDocument document;      
        int start, end, offset1,length1;     
        private JButton button;         
        JFrame frame;
        
                  
        public Form()  
        {  
            super();
              frame = new JFrame();
              
            //Declaring the instance variables  
            textPane = new JTextPane();  
            textPane.setMinimumSize(new Dimension(100,100));  
            
            button = new JButton("Save");  
            button.addActionListener(new Action()); 
              
            document = (DefaultStyledDocument) textPane.getDocument();    
            document.setDocumentFilter(new HighlightFilter());  
              
            keywords = new ArrayList();   
            literals = new ArrayList();   
            
            //Adding Styles  
            style = document.addStyle("blue", null);    
            StyleConstants.setForeground(style, Color.BLUE);                
            style2 = document.addStyle("red", null);  
            StyleConstants.setForeground(style2, Color.RED);            
            
            //Creating the main window 
            south = new JPanel();  
            south.setLayout(new FlowLayout());  
            south.add(button);                      
            scroll = new JScrollPane(textPane);  
            
            frame.getContentPane().add(scroll,"Center");  
            frame.getContentPane().add(south,"South");              
            frame.setVisible(true);
            frame.setSize(800,600);
            frame.validate();
            frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);                      
        } 
          
        private class HighlightFilter extends DocumentFilter   
        {    
            
        public void insertString(FilterBypass fb, int offset, String string, AttributeSet attr)    
                throws BadLocationException {    
          if (string.isEmpty()) {    
            fb.insertString(offset, string, attr);        
            
            
          } else {    
            super.insertString(fb, offset, string, attr);    
             offset1 = offset;
            length1 = string.length()+offset;
            
            System.out.println("Offset: "+offset1+" Length: "+length1);
            highlight();    
          }    
        }    
        
        public void remove(FilterBypass fb, int offset, int length)    
                throws BadLocationException {    
          if (length == 0) {    
            fb.remove(offset, length);    
          } else {    
            super.remove(fb, offset, length);    
            offset1 = offset;
            length1 = length;
             System.out.println("Offset: "+offset1+" Length: "+length1);
            highlight();    
          }    
        }    
            
        public void replace(FilterBypass fb, int offset, int length, String text, AttributeSet attrs)    
                throws BadLocationException {    
          if (length == 0 && text.isEmpty()) {    
            fb.replace(offset, length, text, attrs);    
          } else {    
            super.replace(fb, offset, length, text, attrs);    
             offset1 = offset;
            length1 = length;
             System.out.println("Offset: "+offset1+" Length: "+length1);
             highlight();  
          }  } }  
          
        private void highlight()   
        {    
              SwingUtilities.invokeLater(new Runnable()   
              {    
                  int next=0; int end=0;
            
                @Override    
                public void run() {    
                  try {    
                        content = document.getText(offset1, document.getLength()); 
                        
                         /* int start= Utilities.getRowStart(Form.this,Math.max(0,offset1-1));
                                int end=Utilities.getWordStart(Form.this, offset1()+document.getLength());
                                System.out.println(e);
                                String text=doc.getText(start, end-start);*/
                        
                    for (String word : content.split("\\s")) {    
                    next = content.indexOf(word, next);    
                     end = next + word.length();    
                    
                     document.setCharacterAttributes(next, end,    
                     textPane.getStyle(keywords.contains(word) ? "blue" : literals.contains(word)? "red":"default"),true);    
                     next = end;    
                }    
              } catch (BadLocationException ex) {    
                ex.printStackTrace();    
              }    
            }    
          });    
            }  
          
        private class Action implements ActionListener  
        {  
            public void actionPerformed(ActionEvent ae)  
            {                 
                java = new JavaKeywords();          
                keywords = java.getKeywords();  
                literals = java.getLiterals();  
                highlight();  
            }  
        }  
        
       public static void main(String[] args) throws Exception {   
            SwingUtilities.invokeLater(new Runnable()   
            {    
              @Override    
              public void run() {    
               Form f = new Form();  
              }    
            });    
          }   
    }  

please help...........

[Darryl Burke]

I'm a little tied up with something else (and shall be for most of the coming week) but this is precisely what I have been advising against:

content = document.getText(offset1, document.getLength());

Without having tried it, I feel you can use the methods of the Utilities class so that you examine only the complete words around the offset.

I rather think you need to also pass the length of the inserted string, for an insertion. Then use getPreviousWord(...) for the offset, and getNextWord(...) for the offset+string.length() and examine and highlight only within that range. Why search through a whole lot of stuff that hasn't just changed?

[Yohan Weerasinghe]

Darryl Burke wrote:I'm a little tied up with something else (and shall be for most of the coming week)

OK, Now I feel bit sad But I really appreciate you helped me even when you are very busy with your work. Thanks a lot for that..


I am on my way to check your suggestions. Unfortunately, we have heavy rains here and I have to wait until this rain is over to turn on my computer

[Yohan Weerasinghe]

Hi,

Thanks a lot for the help!! It worked!!! Here is my code

   package Normal;  
      
import Keywords.JavaKeywords;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.FlowLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.ArrayList;
import java.util.List;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.swing.*;
import javax.swing.text.*;
      
    public class Form extends JEditorPane  
    {  
        private JTextPane textPane;  
        private JPanel south;
        private JScrollPane scroll;  
        private List<String> keywords, literals; 
        private String  content;  
        public String documentType;            
        private Style style, style2;           
        private KeywordConnector java;           
        private DefaultStyledDocument document;      
        int start, end, offset1,length1;     
        private JButton button;         
        JFrame frame;
        
                  
        public Form()  
        {  
            super();
              frame = new JFrame();
              
            //Declaring the instance variables  
            textPane = new JTextPane();  
            textPane.setMinimumSize(new Dimension(100,100));  
            
            button = new JButton("Save");  
            button.addActionListener(new Action()); 
              
            document = (DefaultStyledDocument) textPane.getDocument();    
            document.setDocumentFilter(new HighlightFilter());  
              
            keywords = new ArrayList();   
            literals = new ArrayList();   
            
            //Adding Styles  
            style = document.addStyle("blue", null);    
            StyleConstants.setForeground(style, Color.BLUE);                
            style2 = document.addStyle("red", null);  
            StyleConstants.setForeground(style2, Color.RED);            
            
            //Creating the main window 
            south = new JPanel();  
            south.setLayout(new FlowLayout());  
            south.add(button);                      
            scroll = new JScrollPane(textPane);  
            
            frame.getContentPane().add(scroll,"Center");  
            frame.getContentPane().add(south,"South");              
            frame.setVisible(true);
            frame.setSize(800,600);
            frame.validate();
            frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);                      
        } 
          
        private class HighlightFilter extends DocumentFilter   
        {    
            
        public void insertString(FilterBypass fb, int offset, String string, AttributeSet attr)    
                throws BadLocationException {    
          if (string.isEmpty()) {    
            fb.insertString(offset, string, attr);        
            
            
          } else {    
            super.insertString(fb, offset, string, attr);    
             offset1 = offset;
            length1 = string.length()+offset;
            System.out.println(string.length());
            
            System.out.println("Offset: "+offset1+" Length: "+length1);
            highlight();    
          }    
        }    
        
        public void remove(FilterBypass fb, int offset, int length)    
                throws BadLocationException {    
          if (length == 0) {    
            fb.remove(offset, length);    
          } else {    
            super.remove(fb, offset, length);    
            offset1 = offset;
            length1 = length;
             System.out.println("Offset: "+offset1+" Length: "+length1);
            highlight();    
          }    
        }    
            
        public void replace(FilterBypass fb, int offset, int length, String text, AttributeSet attrs)    
                throws BadLocationException {    
          if (length == 0 && text.isEmpty()) {    
            fb.replace(offset, length, text, attrs);    
          } else {    
            super.replace(fb, offset, length, text, attrs);    
             offset1 = offset;
            length1 = length;
             System.out.println("Offset: "+offset1+" Length: "+length1);
             highlight();  
          }  } }  
          
        private void highlight()   
        {    
              SwingUtilities.invokeLater(new Runnable()   
              {    
                  int next=0; int end=0;
            
                @Override    
                public void run() {    
                  try {    
                        //content = document.getText(0, document.getLength()); 
                        
                        int preWord =Utilities.getPreviousWord(textPane, offset1);
                        
                        if(preWord<0)
                        {
                            preWord=preWord*-1;
                        }
                        System.out.println("Previous Word: "+preWord);
                        
                        int wordEnd = Utilities.getWordEnd(textPane, offset1);
                      
                        System.out.println("Word End: "+wordEnd);
                        
                       System.out.println("The Text: "+document.getText(preWord,wordEnd-preWord));
                       
                       content = document.getText(preWord,(wordEnd-preWord)-1);
                       
                       System.out.println("Length: "+(wordEnd-preWord));
                       
                    for (String word : content.split("\\s")) {    
                    next = content.indexOf(word, next);    
                     end = next + word.length();    
                    
                     document.setCharacterAttributes(preWord, word.length(),    
                     textPane.getStyle(keywords.contains(word) ? "blue" : literals.contains(word)? "red":"default"),true);    
                     next = end;    
                }    
              } catch (BadLocationException ex) {    
                ex.printStackTrace();    
              }    
            }    
          });    
            }  
          
        private class Action implements ActionListener  
        {  
            public void actionPerformed(ActionEvent ae)  
            {                 
                java = new JavaKeywords();          
                keywords = java.getKeywords();  
                literals = java.getLiterals();  
                
                
                int next=0; int end=0;
            try {
                content = document.getText(0, document.getLength());
            } catch (BadLocationException ex) {
                Logger.getLogger(Form.class.getName()).log(Level.SEVERE, null, ex);
            }
                
                for (String word : content.split("\\s")) {    
                    next = content.indexOf(word, next);    
                     end = next + word.length();    
                    
                     document.setCharacterAttributes(next, end,    
                     textPane.getStyle(keywords.contains(word) ? "blue" : literals.contains(word)? "red":"default"),true);    
                     next = end;    
                }    
            }  
        }  
        
       public static void main(String[] args) throws Exception {   
            SwingUtilities.invokeLater(new Runnable()   
            {    
              @Override    
              public void run() {    
               Form f = new Form();  
              }    
            });    
          }   
    }   

Anyway, I had to use getWordEnd() instead of getNextWord() because getNextWord() is keep on throwing exceptions.

Thanks again for the help! I really appreciate it!!!