// PageRequest的构造又会涉及到Sort及其内部类Direction和Order

// org.springframework.data.domain.Sort

// org.springframework.data.domain.Sort.Direction

// org.springframework.data.domain.Sort.Order

//---------------------------------------------

//排序的构造方法及其使用示列

//---------------------------------------------

/**

* Creates a new Sort instance using the given Orders.

*

* @param orders must not be  null.

*/

public Sort(Order... orders);

/*使用示列*/

// new Sort(new Order(Direction.DESC, "id"));

/**

* Creates a new Sort instance.

*

* @param orders must not be  null or contain  null.

*/

public Sort(List<Order> orders);

/*使用示列*/

// new Sort(Arrays.asList(new Order(Direction.DESC,"name"),new Order(Direction.ASC,"age")));

/**

* Creates a new Sort instance. Order defaults to Direction#ASC.

*

* @param properties must not be  null or contain  null or empty strings

*/

public Sort(String... properties);

/*使用示列*/

// new Sort("name","age");

/**

* Creates a new Sort instance.

*

* @param direction defaults to  Sort#DEFAULT_DIRECTION (for  null cases, too)

* @param properties must not be  null, empty or contain  null or empty strings.

*/

public Sort(Direction direction, String... properties);

/*使用示列*/

// new Sort(Direction.DESC,"name","age");

/**

* Creates a new Sort} instance.

*

* @param direction defaults to  Sort#DEFAULT_DIRECTION (for  null cases, too)

* @param properties must not be  null or contain  null or empty strings.

*/

public Sort(Direction direction, List<String> properties);

/*使用示列*/

// new Sort(Direction.DESC, Arrays.asList("name","age"));

//---------------------------------------------

// PageRequest的构造方法

//---------------------------------------------

/**

* Creates a new PageRequest. Pages are zero indexed, thus providing 0 for page will return the first

* page.

*

* @param page zero-based page index.

* @param size the size of the page to be returned.

*/

public PageRequest(int page, int size) {

    this(page, size, null);

}

/**

* Creates a new PageRequest with sort parameters applied.

*

* @param page zero-based page index.

* @param size the size of the page to be returned.

* @param direction the direction of the Sort to be specified, can be null.

* @param properties the properties to sort by, must not be null or empty.

*/

public PageRequest(int page, int size, Direction direction, String... properties) {

    this(page, size, new Sort(direction, properties));

}

/**

* Creates a new PageRequest with sort parameters applied.

*

* @param page zero-based page index.

* @param size the size of the page to be returned.

* @param sort can be null.

*/

public PageRequest(int page, int size, Sort sort) {

    super(page, size);

    this.sort = sort;

}