ShowHTMLViews.java Source code

Introduction

Here is the source code for ShowHTMLViews.java

Source

/*
Core SWING Advanced Programming 
By Kim Topley
ISBN: 0 13 083292 8       
Publisher: Prentice Hall  
*/

import java.beans.PropertyChangeEvent;
import java.beans.PropertyChangeListener;
import java.io.PrintStream;
import java.util.Enumeration;

import javax.swing.JEditorPane;
import javax.swing.JFrame;
import javax.swing.JScrollPane;
import javax.swing.UIManager;
import javax.swing.text.AttributeSet;
import javax.swing.text.BadLocationException;
import javax.swing.text.Document;
import javax.swing.text.Element;
import javax.swing.text.JTextComponent;
import javax.swing.text.View;

public class ShowHTMLViews {
    public static void main(String[] args) {
        try {
            UIManager.setLookAndFeel("com.sun.java.swing.plaf.windows.WindowsLookAndFeel");
        } catch (Exception evt) {
        }

        try {
            JFrame f = new JFrame("HTML Document View Structure");
            final JEditorPane ep = new JEditorPane(args[0]);
            ep.setEditable(false);
            f.getContentPane().add(new JScrollPane(ep));
            f.setSize(400, 300);
            f.setVisible(true);

            ep.addPropertyChangeListener(new PropertyChangeListener() {
                public void propertyChange(PropertyChangeEvent evt) {
                    if (evt.getPropertyName().equals("page")) {
                        System.out.println("Document:\n");
                        HTMLDocDisplay.displayModel(ep, System.out);
                        System.out.println("\n\nViews:\n");
                        HTMLViewDisplayer.displayViews(ep, System.out);
                    }
                }
            });
        } catch (Exception e) {
            System.out.println(e);
            System.exit(1);
        }
    }
}

class HTMLDocDisplay {
    public static void displayAttributes(AttributeSet a, int indent, PrintStream out) {
        if (a == null)
            return;

        a = a.copyAttributes();
        Enumeration x = a.getAttributeNames();
        for (int i = 0; i < indent; i++) {
            out.print("  ");
        }
        if (x != null) {
            out.println("ATTRIBUTES:");
            while (x.hasMoreElements()) {

                for (int i = 0; i < indent; i++) {
                    out.print("  ");
                }
                Object attr = x.nextElement();
                out.println(
                        " (" + attr + ", " + a.getAttribute(attr) + ")" + " [" + getShortClassName(attr.getClass())
                                + "/" + getShortClassName(a.getAttribute(attr).getClass()) + "] ");
            }
        } else {
            out.println("No attributes");
        }
        if (a.getResolveParent() != null) {
            displayAttributes(a.getResolveParent().copyAttributes(), indent + 1, out);
        }
    }

    public static void displayModel(JTextComponent comp, PrintStream out) {
        Document doc = comp.getDocument();
        Element e = doc.getDefaultRootElement();
        displayElement(doc, e, 0, out);
    }

    public static void displayElement(Document doc, Element e, int indent, PrintStream out) {
        for (int i = 0; i < indent; i++) {
            out.print("  ");
        }
        out.println("===== Element Class: " + getShortClassName(e.getClass()));
        for (int i = 0; i < indent; i++) {
            out.print("  ");
        }
        int startOffset = e.getStartOffset();
        int endOffset = e.getEndOffset();
        out.println("Offsets [" + startOffset + ", " + endOffset + "]");
        AttributeSet a = e.getAttributes();
        Enumeration x = a.getAttributeNames();
        for (int i = 0; i < indent; i++) {
            out.print("  ");
        }
        out.println("ATTRIBUTES:");
        while (x.hasMoreElements()) {
            for (int i = 0; i < indent; i++) {
                out.print("  ");
            }
            Object attr = x.nextElement();
            out.println(" (" + attr + ", " + a.getAttribute(attr) + ")" + " [" + getShortClassName(attr.getClass())
                    + "/" + getShortClassName(a.getAttribute(attr).getClass()) + "] ");
        }

        // Display the text for a leaf element
        if (e.isLeaf()) {
            try {
                String str = doc.getText(startOffset, endOffset - startOffset);
                if (str.length() > 40) {
                    str = str.substring(0, 40);
                }
                if (str.length() > 0) {
                    for (int i = 0; i < indent; i++) {
                        out.print("  ");
                    }
                    out.println("[" + str + "]");
                }
            } catch (BadLocationException ex) {
            }
        }

        // Display child elements
        int count = e.getElementCount();
        for (int i = 0; i < count; i++) {
            displayElement(doc, e.getElement(i), indent + 1, out);
        }
    }

    public static String getShortClassName(Class clazz) {
        String className = clazz.getName();
        return className.substring(className.lastIndexOf(".") + 1);
    }
}

class HTMLViewDisplayer {
    public static void displayViews(JTextComponent comp, PrintStream out) {
        View rootView = comp.getUI().getRootView(comp);
        displayView(rootView, 0, comp.getDocument(), out);
    }

    public static void displayView(View view, int indent, Document doc, PrintStream out) {
        String name = view.getClass().getName();
        for (int i = 0; i < indent; i++) {
            out.print("  ");
        }

        int start = view.getStartOffset();
        int end = view.getEndOffset();
        out.println(name + "; offsets [" + start + ", " + end + "]");
        for (int i = 0; i < indent; i++) {
            out.print("  ");
        }
        HTMLDocDisplay.displayAttributes(view.getAttributes(), indent, out);
        int viewCount = view.getViewCount();
        if (viewCount == 0) {
            int length = Math.min(32, end - start);
            try {
                String txt = doc.getText(start, length);
                for (int i = 0; i < indent + 1; i++) {
                    out.print("  ");
                }
                out.println("[" + txt + "]");
            } catch (BadLocationException e) {
            }
        } else {
            for (int i = 0; i < viewCount; i++) {
                displayView(view.getView(i), indent + 1, doc, out);
            }
        }
        out.println("");
    }
}