public boolean validate(IDocument document, int offset, DocumentEvent event) { return false;}
public boolean validate(IDocument document, int offset, DocumentEvent event) {  String insert= getDisplayString(); if (insert == null) return false;  int start= offset - insert.length(); if (start >= 0 && offset <= document.getLength()) { try { String content= document.get(start, offset - start); while (content.length() > 0) { if (insert.startsWith(content)) return true; else content= content.substring(1); } } catch (BadLocationException e) { JavaPlugin.log(e);  } } return false; }
		public boolean validate(IDocument document, int offset, DocumentEvent event) { return false;}