How to display query results by page in Struts

Messagelist. do-> messagelist. jsp

Use messagelist. do? Start = 0 to display the first page

Parameter description:

List: Information list

Start: start position

Page: Number of information displayed on each page

Previous: Start position of the previous page

Next: Start position of the next page

The perform in MessageListAction is written as follows:

Bytes ------------------------------------------------------------------------------------

Int start = Integer. parseInt (request. getParameter ("start "));

System. out. println ("Start:" + start );

Int page = 4;

// Create a message list

Message [] list = new Message [16];

For (int I = 0; I <list. length; I ++ ){

List [I] = new Message (I, "message" + I );

}

Request. setAttribute ("list", list );

Request. setAttribute ("start", new Integer (start ));

Request. setAttribute ("page", new Integer (page ));

// If there is a previous page, set the previous variable

Int previous = start-page;

If (previous> = 0 ){

Request. setAttribute ("previous", new Integer (previous ));

System. out. println ("previous:" + previous );

}

// If there is a next page, set the next variable

Int next = start + page;

If (next <list. length ){

Request. setAttribute ("next", new Integer (next ));

System. out. println ("next:" + next );

}

Return (mapping. findForward ("success "));

Bytes ------------------------------------------------------------------------------------

The content in messagelist. jsp is as follows:

Bytes ------------------------------------------------------------------------------------

<Logic: iterate id = "message" name = "list" offset = "start" length = "page">

<Br>

ParamId = "id" paramName = "message" paramProperty = "id"

Page = "/messagedetail. do">

<Bean: write name = "message" property = "name"/>

</Html: link>

</Logic: iterate>

<Logic: present name = "previous">

<Br>

ParamId = "start" paramName = "previous"

Page = "/messagelist. do">

Previous Page

</Html: link>

</Logic: present>

<Logic: present name = "next">

<Br>

ParamId = "start" paramName = "next"

Page = "/messagelist. do">

Next Page

</Html: link>

</Logic: present>

Bytes ------------------------------------------------------------------------------------

This example illustrates the usage of logic: iterate in pages.

Every time messagelist. do processes all messages, the performance can be optimized.

For example, store the message array in the session.