Datasheet

want to use a validator as a mechanism to check a condition that is more complicated than simply “pre-

sent” or “not present.” If either of these conditions is false, then the

LuceneValidator will throw a

ValidatorException.

Now that we have managed the major logical parts of the

LucenePortlet, we will review the presenta-

tion aspects of the portlet. The following code shows

search_view.jsp, which presents a user interface

for searching:

<%@ page import=”javax.portlet.PortletURL” %>

<%@ taglib uri=”http://java.sun.com/portlet” prefix=”portlet” %>

<portlet:defineObjects/>

<tr>

<th>SEARCH</th>

</tr>

<tr>

<td>

<FORM action=”<portlet:actionURL />” method=”POST”>

</FORM>

</td>

</tr>

</table>

In this JSP, we see the first use of the Portlet Tag Library. These tags provide access to the portlet from

within a JSP. The most interesting use here is the

actionURL tag, which is the proper way of creating

links within a portlet application. Creating them as was traditionally done in Web applications, by

appending parameters to an HTTP query string, is not correct, as it may omit portal-specific references

that should be included in the URL.

Logically, we now need a page to view the results of our search. The following code provides a search

results page:

<%@ page import=”java.util.*,org.apache.lucene.search.*,java.text.*” %>

<%@ page import=”org.apache.lucene.document.*” %>

<jsp:useBean id=”hits” scope=”request” type=”org.apache.lucene.search.Hits”/>

String shaded = “silver”;

DecimalFormat form = new DecimalFormat(“#”);

<p>

<i><b><%=hits.length()%></b></i> Documents match your request.

<p>

for (int i = 0; i < 25; i++) {

Document doc = hits.doc(i);

if (i % 2 == 0) {

shaded = “silver”;

The Java Portlet API (JSR 168)

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