public Predicate getPredicateAnd(T entity, Root<T> root, CriteriaBuilder cb) throws IntrospectionException        , InvocationTargetException, IllegalAccessException {    try {        //通过反射获取类型Class<?> c = entity.getClass();        //获取类的字段Field[] fields = c.getDeclaredFields();        List<Predicate> predicateList = new ArrayList();        for (Field field : fields) {            PropertyDescriptor pd = new PropertyDescriptor(field.getName(), c);            //获得get方法Method getMethod = pd.getReadMethod();            //执行get方法返回一个ObjectObject fieldVal = getMethod.invoke(entity);            if (fieldVal != null && !fieldVal.equals(0)) {                Path<String> path = root.get(field.getName());                Predicate p = cb.equal(path, fieldVal);                predicateList.add(p);            }        }        return cb.and(predicateList.toArray(new Predicate[]{}));    } catch (Exception e) {        log.error(e.getMessage());    }    return null;}

public T findOne(final T entity) {        return getSpecDao().findOne(new Specification<T>() {            @Override            public Predicate toPredicate(Root<T> root, CriteriaQuery<?> query, CriteriaBuilder cb) {                      try {                    query.where( getPredicateAnd(entity, root, cb));                } catch (InvocationTargetException e) {                    e.printStackTrace();                } catch (IllegalAccessException e) {                    e.printStackTrace();                } catch (IntrospectionException e) {                    e.printStackTrace();                }                return null;            }        });    }