求教大神，如何让Annotation的成员成为非必填

@Documented@Target(ElementType.TYPE)@Retention(RetentionPolicy.RUNTIME)public @interface Table {	String name();	String primaryKey();	}@Documented@Target(ElementType.FIELD)@Retention(RetentionPolicy.RUNTIME)public @interface Column {	String name();	boolean notNull();	boolean unique();	String check();	public String defaultValue();	String collate();}@Table(name = "", primaryKey = "")public class Task {		@Column(check = "", collate = "", defaultValue = "", name = "", notNull = false, unique = false)	private String createTime;		@Column(check = "", collate = "", defaultValue = "", name = "", notNull = false, unique = false)	private String name;		}

我不希望Column的所有成员都显示出来。