通過JPA注解獲取某個類的主鍵字段

public String getPkColumn(String className) {
    String pkColumn = null;
    try {
        Class clazz = Class.forName(className);
        Field[] fields = clazz.getDeclaredFields();
        for (Field field : fields) {
            if(field.getAnnotation(Id.class) != null){
                Annotation annotation = field.getAnnotation(Column.class);
                pkColumn = ((Column)annotation).name();
                break;
            }
        }
    } catch (ClassNotFoundException e) {
        e.printStackTrace();
    } finally {
        return pkColumn;
    }
}