Bug 53010 Editor preferences do not take effect on open editors
I-20040224 Go to the Java > Editor > Syntax preference page. Change the keyword color to red. Press Ok. At this point, we use to see the preview update. Not on this build (problem #1). Press Ok, and close the pref dialog. The java editor that was already open did not update. I had to close it and reopen it for the colors to take effect (problem #2)
org.eclipse.jdt.ui/ui/org/eclipse/jdt/ui/text/JavaSourceViewerConfiguration.java
int tabWidth= CodeFormatterUtil.getTabWidth();
		boolean useSpaces= getNewPreferenceStore().getBoolean(SPACES_FOR_TABS);
		
		for (int i= 0; i <= tabWidth; i++) {
		    StringBuffer prefix= new StringBuffer();
			if (useSpaces) {
			    for (int j= 0; j + i < tabWidth; j++)
			    	prefix.append(' ');
		    	
				if (i != 0)
		    		prefix.append('\t');				
			} else {    
			    for (int j= 0; j < i; j++)
			    	prefix.append(' ');
		    	
				if (i != tabWidth)
		    		prefix.append('\t');
			}
			
			vector.add(prefix.toString());
		}
		vector.add(""); 
		
		return (String[]) vector.toArray(new String[vector.size()]);
	}
	/*
	 * @see SourceViewerConfiguration#getTabWidth(ISourceViewer)
	 */