Bug 6969 NPE in code formatter preference page
20011206 Open the code formatter preference page Go to the style tab Go to the number of spaces... field Backspace until the field is empty NPE
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/preferences/CodeFormatterPreferencePage.java
private static final String PREF_NEWLINE_OPENING_BRACES= "org.eclipse.jdt.core.formatter.newline.openingBrace";
	private static final String PREF_NEWLINE_CONTROL_STATEMENT= "org.eclipse.jdt.core.formatter.newline.controlStatement";
	private static final String PREF_NEWLINE_CLEAR_ALL= "org.eclipse.jdt.core.formatter.newline.clearAll";
	private static final String PREF_NEWLINE_ELSE_IF= "org.eclipse.jdt.core.formatter.newline.elseIf";
	private static final String PREF_NEWLINE_EMPTY_BLOCK= "org.eclipse.jdt.core.formatter.newline.emptyBlock";
	private static final String PREF_LINE_SPLIT= "org.eclipse.jdt.core.formatter.lineSplit";	
	private static final String PREF_STYLE_COMPACT_ASSIGNEMENT= "org.eclipse.jdt.core.formatter.style.assignment";	
	private static final String PREF_TAB_CHAR= "org.eclipse.jdt.core.formatter.tabulation.char";	
	private static final String PREF_TAB_SIZE= "org.eclipse.jdt.core.formatter.tabulation.size";
	
	private static final String INSERT= "insert";
	private static final String DO_NOT_INSERT= "do not insert";
	
	private static final String COMPACT= "compact";
	private static final String NORMAL= "normal";
	
	private static final String TAB= "tab";
	private static final String SPACE= "space";
	
	private static final String CLEAR_ALL= "clear all";
	private static final String PRESERVE_ONE= "preserve one";
	
	private static String[] getAllKeys() {
		return new String[] {
			PREF_NEWLINE_OPENING_BRACES, PREF_NEWLINE_CONTROL_STATEMENT, PREF_NEWLINE_CLEAR_ALL,
			PREF_NEWLINE_ELSE_IF, PREF_NEWLINE_EMPTY_BLOCK, PREF_LINE_SPLIT,