if (fSelectedType == null) return SearchMessages.getString("ImplementOccurrencesFinder.invalidTarget");
	public String initialize(CompilationUnit root, int offset, int length) {		ASTNode node= NodeFinder.perform(root, offset, length);		if (!(node instanceof Name))			return SearchMessages.getString("ImplementOccurrencesFinder.invalidTarget");  //$NON-NLS-1$		fSelectedName= ASTNodes.getTopMostName((Name)node);		ASTNode parent= fSelectedName.getParent();		if (!(parent instanceof SimpleType))			return SearchMessages.getString("ImplementOccurrencesFinder.invalidTarget");  //$NON-NLS-1$		ASTNode typeDeclaration= parent.getParent();		if (!(typeDeclaration instanceof TypeDeclaration))			return SearchMessages.getString("ImplementOccurrencesFinder.invalidTarget");  //$NON-NLS-1$				fSelectedType= fSelectedName.resolveTypeBinding();		fStart= typeDeclaration;		return null;	}