Bug 54658 Bug in Code Formatter > Line Wrapping
Code Formatter > Line Wrapping: The preview is not shown correctly from the beginning. The "Set line width for preview window" number has to be reset to another OR even THE SAME value to correct the display.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/preferences/formatter/LineWrappingTabPage.java
/**
     * Represents a line wrapping category. All members are final.
     */
	private final static class Category {
		public final String key;
		public final String name;
		public final String previewText;
		public final List children;
		
		public int index;
		public Category(String key, String previewText, String name) {
			this.key= key;
			this.name= name;
			this.previewText= previewText != null ? createPreviewHeader(name) + previewText : null; 
			children= new ArrayList();
		}
		
		public Category(String name) {
		    this(null, null, name);
		}
		
		public String toString() {
			return name;
		}
	}
	
	private final static String PREF_CATEGORY_INDEX= JavaUI.ID_PLUGIN + "formatter_page.line_wrapping_tab_page.last_category_index";  
	
	
	private final class CategoryListener implements ISelectionChangedListener, IDoubleClickListener {