1. Define the iterator tag processing class:
| The code is as follows: |
Copy code |
Package mckee;
Import java. io. IOException;
Import java. util. Collection;
Import javax. servlet. jsp. JspException;
Import javax. servlet. jsp. tagext. SimpleTagSupport;
Public class IteratorTag extends SimpleTagSupport
{
// Specify the set
Private String collection;
// Specify the set element
Private String item;
// Getter and setter
Public String getCollection (){
Return collection;
}
Public void setCollection (String collection ){
This. collection = collection;
}
Public String getItem (){
Return item;
}
Public void setItem (String item ){
This. item = item;
}
Public void doTag () throws JspException, IOException
{
// Obtain the set
Collection itemList = (Collection) getJspContext (). getAttribute (collection );
// Traverse the set
For (Object s: itemList)
{
// Set the set element to the page range
GetJspContext (). setAttribute (item, s );
// Output Tag body
GetJspBody (). invoke (null );
}
}
} |
2. Create a tld file
| The code is as follows: |
Copy code |
<? Xml version = "1.0" encoding = "UTF-8"?>
<Taglib xmlns = "http://java.sun.com/xml/ns/j2ee"
Xmlns: xsi = "http://www.w3.org/2001/XMLSchema-instance"
Xsi: schemaLocation = "http://java.sun.com/xml/ns/j2ee http://java.sun.com/xml/ns/j2ee/web-jsptaglibrary_2_0.xsd"
Version = "2.0">
<Tlib-version> 1.0 </tlib-version>
<Short-name> mytag </short-name>
<Uri>/mytag </uri> <! -- This is very important. The jsp page locates the tag library based on the uri -->
<Tag>
<Name> iterator </name> <! -- Define the tag name -->
<Tag-class> mckee. IteratorTag </tag-class> <! -- Define tag processing class -->
<Body-content> scriptless </body-content> <! -- Define the TAG Body -->
<! -- Configure the tag attributes of collection and item -->
<Attribute>
<Name> collection </name>
<Required> true </required>
<Fragment> true </fragment>
</Attribute>
<Attribute>
<Name> item </name>
<Required> true </required>
<Fragment> true </fragment>
</Attribute>
</Tag>
</Taglib>
|
2. Create a tld file
| The code is as follows: |
Copy code |
<? Xml version = "1.0" encoding = "UTF-8"?>
<Taglib xmlns = "http://java.sun.com/xml/ns/j2ee"
Xmlns: xsi = "http://www.w3.org/2001/XMLSchema-instance"
Xsi: schemaLocation = "http://java.sun.com/xml/ns/j2ee http://java.sun.com/xml/ns/j2ee/web-jsptaglibrary_2_0.xsd"
Version = "2.0">
<Tlib-version> 1.0 </tlib-version>
<Short-name> mytag </short-name>
<Uri>/mytag </uri> <! -- This is very important. The jsp page locates the tag library based on the uri -->
<Tag>
<Name> iterator </name> <! -- Define the tag name -->
<Tag-class> mckee. IteratorTag </tag-class> <! -- Define tag processing class -->
<Body-content> scriptless </body-content> <! -- Define the TAG Body -->
<! -- Configure the tag attributes of collection and item -->
<Attribute>
<Name> collection </name>
<Required> true </required>
<Fragment> true </fragment>
</Attribute>
<Attribute>
<Name> item </name>
<Required> true </required>
<Fragment> true </fragment>
</Attribute>
</Tag>
</Taglib>
|
3. Test tags on the jsp page
| The code is as follows: |
Copy code |
<% @ Page language = "java" contentType = "text/html; charset = UTF-8" pageEncoding = "UTF-8" %>
<% @ Page import = "java. util. *" %>
<% @ Taglib uri = "/mytag" prefix = "mytag" %>
<! DOCTYPE html PUBLIC "-// W3C // dtd html 4.01 Transitional // EN" "http://www.w3.org/TR/html4/loose.dtd">
<Html>
<Head>
<Meta http-equiv = "Content-Type" content = "text/html; charset = UTF-8">
<Title> powered by http://www.111cn.net </title>
</Head>
<Body>
<%
List <String> arr = new ArrayList <String> ();
Arr. add ("java tutorial ");
Arr. add ("http://www.111cn.net ");
PageContext. setAttribute ("arr", arr );
%>
<Mytag: iterator collection = "arr" item = "item">
$ {Pagination. item} <br>
</Mytag: iterator>
</Body>
</Html>
|
