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Java binary compatibility issue: sun.font.FontManager class became interface

I am using the Lobo - Java Web Browser library, and it gives me an exception which after some research I determined could be due to the library having been complied against an older version of Java.

The code is as follows:

import java.io.IOException;
import org.lobobrowser.html.UserAgentContext;
import org.lobobrowser.html.parser.DocumentBuilderImpl;
import org.lobobrowser.html.parser.InputSourceImpl;
import org.lobobrowser.html.test.SimpleUserAgentContext;
import org.xml.sax.SAXException;

public class Cobratest
{
    public static void main(String[] args) throws SAXException, IOException
    {
        UserAgentContext uAgent = new SimpleUserAgentContext();
        DocumentBuilderImpl docBuild = new DocumentBuilderImpl(uAgent);
        docBuild.parse(new InputSourceImpl("http://dic.amdz.com/"));
    }
}

and the stack trace is:

 Exception in thread "main" java.lang.IncompatibleClassChangeError: Found interface sun.font.FontManager, but class was expected
    at org.lobobrowser.util.gui.FontFactory.createFont(FontFactory.java:210)
    at org.lobobrowser.util.gui.FontFactory.createFont_Impl(FontFactory.java:180)
    at org.lobobrowser.util.gui.FontFactory.createFont(FontFactory.java:127)
    at org.lobobrowser.util.gui.FontFactory.getFont(FontFactory.java:98)
    at org.lobobrowser.html.style.StyleSheetRenderState.<clinit>(StyleSheetRenderState.java:43)
    at org.lobobrowser.html.domimpl.NodeImpl.<clinit>(NodeImpl.java:39)
    at org.lobobrowser.html.parser.DocumentBuilderImpl.createDocument(DocumentBuilderImpl.java:143)
    at org.lobobrowser.html.parser.DocumentBuilderImpl.parse(DocumentBuilderImpl.java:97)

when I examined org.lobobrowser.util.gui.FontFactory.createFont I found out there is an interface called FontManager which changed from the previous version of Java. In this FontFactory class, they used a class of this interface which is no longer available. How can I fix this problem?

the interface FontManager:

package sun.font;

import java.awt.Font;
import java.awt.FontFormatException;
import java.io.File;

public interface FontManager {

    public static final int NO_FALLBACK = 0;
    public static final int PHYSICAL_FALLBACK = 1;
    public static final int LOGICAL_FALLBACK = 2;

    public boolean registerFont(Font font);

    public void deRegisterBadFont(Font2D font2d);

    public Font2D findFont2D(String string, int i, int i1);

    public Font2D createFont2D(File file, int i, boolean bln, CreatedFontTracker cft) throws FontFormatException;

    public boolean usingPerAppContextComposites();

    public Font2DHandle getNewComposite(String string, int i, Font2DHandle fdh);

    public void preferLocaleFonts();

    public void preferProportionalFonts();
}

and the class used in the library which is not available:

   return FontManager.getCompositeFontUIResource(new Font(name, style, size));
like image 401
lonesome Avatar asked Feb 12 '12 04:02

lonesome


2 Answers

I think 'sun.font.FontManager'was removed with Java7, so if you must use it (I'd recommend against it and look for another package instead) you could try running it with java6.

like image 123
Peter Svensson Avatar answered Nov 18 '22 13:11

Peter Svensson


The LoboBrowser project has been superseded by LoboEvolution, but there's a patch that's mentioned for the obsolete LoboBrowser implementation.

Update FontFactory.java to import a public method and revise the createFont method as follows:

import static javax.swing.text.StyleContext.*;

private Font createFont(String name, int style, int size) {
  return getDefaultStyleContext().getFont(name, style, size);
}
like image 28
alfonx Avatar answered Nov 18 '22 13:11

alfonx