mirror of https://github.com/apache/lucene.git
341 lines
16 KiB
HTML
341 lines
16 KiB
HTML
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
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<!-- Content Stylesheet for Site -->
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<!-- start the processing -->
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<!-- ====================================================================== -->
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<!-- Main Page Section -->
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<!-- ====================================================================== -->
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<html>
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<head>
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<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1"/>
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<meta name="author" value="Andrew C. Oliver">
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<meta name="email" value="acoliver@apache.org">
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<title>Jakarta Lucene - Jakarta Lucene - Basic Demo Sources Walkthrough</title>
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</head>
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<body bgcolor="#ffffff" text="#000000" link="#525D76">
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<table border="0" width="100%" cellspacing="0">
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<!-- TOP IMAGE -->
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<tr>
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<td align="left">
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<a href="http://jakarta.apache.org"><img src="http://jakarta.apache.org/images/jakarta-logo.gif" border="0"/></a>
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</td>
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<td align="right">
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<a href="http://jakarta.apache.org/lucene/"><img src="./images/lucene_green_300.gif" alt="Jakarta Lucene" border="0"/></a>
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</td>
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</tr>
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</table>
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<table border="0" width="100%" cellspacing="4">
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<tr><td colspan="2">
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<hr noshade="" size="1"/>
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</td></tr>
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<tr>
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<!-- LEFT SIDE NAVIGATION -->
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<td width="20%" valign="top" nowrap="true">
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<p><strong>About</strong></p>
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<ul>
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<li> <a href="./index.html">Overview</a>
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</li>
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<li> <a href="./powered.html">Powered by Lucene</a>
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</li>
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<li> <a href="./whoweare.html">Who We Are</a>
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</li>
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<li> <a href="http://jakarta.apache.org/site/mail.html">Mailing Lists</a>
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</li>
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</ul>
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<p><strong>Resources</strong></p>
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<ul>
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<li> <a href="http://lucene.sourceforge.net/cgi-bin/faq/faqmanager.cgi">FAQ (Official)</a>
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</li>
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<li> <a href="http://www.jguru.com/faq/Lucene">JGuru FAQ</a>
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</li>
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<li> <a href="./gettingstarted.html">Getting Started</a>
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</li>
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<li> <a href="http://jakarta.apache.org/site/bugs.html">Bugs</a>
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</li>
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<li> <a href="http://nagoya.apache.org/bugzilla/buglist.cgi?bug_status=NEW&bug_status=ASSIGNED&bug_status=REOPENED&email1=&emailtype1=substring&emailassigned_to1=1&email2=&emailtype2=substring&emailreporter2=1&bugidtype=include&bug_id=&changedin=&votes=&chfieldfrom=&chfieldto=Now&chfieldvalue=&product=Lucene&short_desc=&short_desc_type=allwordssubstr&long_desc=&long_desc_type=allwordssubstr&bug_file_loc=&bug_file_loc_type=allwordssubstr&keywords=&keywords_type=anywords&field0-0-0=noop&type0-0-0=noop&value0-0-0=&cmdtype=doit&order=%27Importance%27">Lucene Bugs</a>
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</li>
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<li> <a href="./queryparsersyntax.html">Query Syntax</a>
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</li>
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<li> <a href="./api/index.html">Javadoc</a>
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</li>
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<li> <a href="./contributions.html">Contributions</a>
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</li>
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<li> <a href="./lucenesandbox.html">Lucene Sandbox</a>
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</li>
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<li> <a href="./resources.html">Articles</a>
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</li>
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</ul>
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<p><strong>Plans</strong></p>
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<ul>
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<li> <a href="./luceneplan.html">Application Extensions</a>
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</li>
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</ul>
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<p><strong>Download</strong></p>
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<ul>
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<li> <a href="http://jakarta.apache.org/site/binindex.html">Binaries</a>
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</li>
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<li> <a href="http://jakarta.apache.org/site/sourceindex.html">Source Code</a>
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</li>
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<li> <a href="http://jakarta.apache.org/site/cvsindex.html">CVS Repositories</a>
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</li>
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</ul>
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<p><strong>Jakarta</strong></p>
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<ul>
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<li> <a href="http://jakarta.apache.org/site/getinvolved.html">Get Involved</a>
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</li>
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<li> <a href="http://jakarta.apache.org/site/acknowledgements.html">Acknowledgements</a>
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</li>
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<li> <a href="http://jakarta.apache.org/site/contact.html">Contact</a>
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</li>
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<li> <a href="http://jakarta.apache.org/site/legal.html">Legal</a>
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</li>
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</ul>
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</td>
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<td width="80%" align="left" valign="top">
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<table border="0" cellspacing="0" cellpadding="2" width="100%">
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<tr><td bgcolor="#525D76">
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<font color="#ffffff" face="arial,helvetica,sanserif">
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<a name="About the Code"><strong>About the Code</strong></a>
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</font>
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</td></tr>
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<tr><td>
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<blockquote>
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<p>
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In this section we walk through the sources behind the basic Lucene Web Application demo.
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Where to find it, its parts, and their function. This section is intended for Java developers
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wishing to understand how to use Jakarta Lucene in their applications or for those involved
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in deploying web applications based on Lucene.
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</p>
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</blockquote>
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</p>
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</td></tr>
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<tr><td><br/></td></tr>
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</table>
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<table border="0" cellspacing="0" cellpadding="2" width="100%">
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<tr><td bgcolor="#525D76">
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<font color="#ffffff" face="arial,helvetica,sanserif">
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<a name="Location of the source (developers/deployers)"><strong>Location of the source (developers/deployers)</strong></a>
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</font>
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</td></tr>
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<tr><td>
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<blockquote>
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<p>
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Relative the directory created when you extracted Lucene or retreived it from CVS, you
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should see a directory called "src" which in turn contains a directory called "jsp".
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This is the root for all of the Lucene web demo.
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</p>
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<p>
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Within this directory you should see the index.jsp class. Bring this up in vi or your
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editor of choice.
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</p>
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</blockquote>
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</p>
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</td></tr>
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<tr><td><br/></td></tr>
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</table>
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<table border="0" cellspacing="0" cellpadding="2" width="100%">
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<tr><td bgcolor="#525D76">
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<font color="#ffffff" face="arial,helvetica,sanserif">
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<a name="index.jsp (developers/deployers)"><strong>index.jsp (developers/deployers)</strong></a>
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</font>
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</td></tr>
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<tr><td>
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<blockquote>
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<p>
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This jsp page is pretty boring by itself. All it does is include a header, display a form and
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include a footer. If you look at the form, it has two fields: query (where you enter your
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search criteria) and maxresults where you specify the number of results per page. If you look
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at the form tag, you'll notice it uses the get method as opposed to the post. While this is
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considered deprecated functionality by the latest w3c specs, its unlikely to go away due to the
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usefulness of being able to bookmark things like searches. By the structure of this JSP it should
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be easy to customize it without even editing this particular file. You could simply change the
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header and footer. Let's look at the header.jsp (located in the same directory) next.
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</p>
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</blockquote>
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</p>
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</td></tr>
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<tr><td><br/></td></tr>
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</table>
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<table border="0" cellspacing="0" cellpadding="2" width="100%">
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<tr><td bgcolor="#525D76">
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<font color="#ffffff" face="arial,helvetica,sanserif">
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<a name="header.jsp (developers/deployers)"><strong>header.jsp (developers/deployers)</strong></a>
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</font>
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</td></tr>
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<tr><td>
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<blockquote>
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<p>
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The header is also very simple by itself. The only thing it does is include the configuration.jsp
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(which you looked at in the last section of this guide) and set the title and a brief header. This
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would be a good place to put your own custom HTML to "pretty" things up a bit. We won't cover the
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footer because all it does is display the footer and close your tags. Let's look at the results.jsp,
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the meat of this application next.
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</p>
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</blockquote>
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</p>
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</td></tr>
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<tr><td><br/></td></tr>
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</table>
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<table border="0" cellspacing="0" cellpadding="2" width="100%">
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<tr><td bgcolor="#525D76">
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<font color="#ffffff" face="arial,helvetica,sanserif">
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<a name="results.jsp (developers)"><strong>results.jsp (developers)</strong></a>
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</font>
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</td></tr>
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<tr><td>
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<blockquote>
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<p>
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The results.jsp had a lot more functionality. Much of it is for paging the search results we'll not
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cover this as its commented well enough. It does not peform any optimizations such as caching results,
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etc. as that would make this a more complex example. The first thing in this page is the actual imports
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for the Lucene classes and Lucene demo classes. These classes are loaded from the jars included in the
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WEB-INF/lib directory in the final war file.
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</p>
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<p>
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You'll notice that this file includes the same header and footer as the "index.jsp". From there the jsp
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constructs an IndexSearcher with the "indexLocation" that was specified in the "configuration.jsp". If there
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is an error of any kind in opening the index, it is diplayed ot the user and a boolean flag is set to tell
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the rest of the sections of the jsp not to continue.
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</p>
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<p>
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From there, this jsp attempts to get the search criteria, the start index (used for paging) and the maximum
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number of results per page. If the maximum results per page is not set or not valid then it and the
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start index are set to default values. If only the start index is invalid it is set to a default value. If
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the criteria isn't provided then a servlet error is thrown (it is assumed that this is the result of url tampering
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or some form of browser malfunction).
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</p>
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<p>
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The jsp moves on to construct a StandardAnalyzer just as in the simple demo, to analyze the search critieria, it
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is passed to the QueryParser along with the criteria to construct a Query object. You'll also notice the
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string literal "contents" included. This is to specify the search should include the the contents and not
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the title, url or some other field in the indexed documents. If there is any error in constructing a Query
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object an error is displayed to the user.
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</p>
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<p>
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In the next section of the jsp the IndexSearcher is asked to search given the query object. the results are
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returned in a collection called "hits". If the length property of the hits collection is 0 then an error
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is displayed to the user and the error flag is set.
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</p>
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<p>
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Finally the jsp iterates through the hits collection and displayed properties of the "Document" objects we talked
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about in the first walkthrough. These objects contain "known" fields specific to their indexer (in this case
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"IndexHTML" constructs a document with "url", "title" and "contents"). You'll notice that these results are paged
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but the search is repeated every time. This is an area where optimization could improve performance for large
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result sets.
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</p>
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</blockquote>
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</p>
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</td></tr>
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<tr><td><br/></td></tr>
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</table>
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<table border="0" cellspacing="0" cellpadding="2" width="100%">
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<tr><td bgcolor="#525D76">
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<font color="#ffffff" face="arial,helvetica,sanserif">
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<a name="More sources (developers)"><strong>More sources (developers)</strong></a>
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</font>
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</td></tr>
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<tr><td>
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<blockquote>
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<p>
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There are additional sources used by the web app that were not specifically covered by either walkthrough. For
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example the HTML parser, the IndexHTML class and HTMLDocument class. These are very similar to the classes
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covered in the first example, however they have properties sepecific to parsing and indexing HTML. This is
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beyond our scope; however, by now you should feel like you're "getting started" with Lucene.
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</p>
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</blockquote>
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</p>
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</td></tr>
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<tr><td><br/></td></tr>
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</table>
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<table border="0" cellspacing="0" cellpadding="2" width="100%">
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<tr><td bgcolor="#525D76">
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<font color="#ffffff" face="arial,helvetica,sanserif">
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<a name="Where to go from here? (Everyone!)"><strong>Where to go from here? (Everyone!)</strong></a>
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</font>
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</td></tr>
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<tr><td>
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<blockquote>
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<p>
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There are a number of things this demo doesn't do or doesn't do quite right. For instance, you may
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have noticed that documents in the root context are unreachable (unless you reconfigure Tomcat to
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support that context or redirect to it), anywhere where the directory doesn't quite match the context mapping,
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you'll have a broken link in your results. If you want to index non-local files or have some other
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needs this isn't supported, plus there may be security issues with running the indexing application from
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your webapps directory. There are a number of things left for you the implementor or developer to do.
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</p>
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<p>
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In time some of these things may be added to Lucene as features (if you've got a good idea we'd love to hear it!),
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but for now: this is where you begin and the search engine/indexer ends. Lastly, one would assume you'd
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want to follow the above advice and customize the application to look a little more fancy than black on
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white with "Lucene Template" at the top. We'll see you on the Lucene Users' or Developers' mailing lists!
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</p>
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</blockquote>
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</p>
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</td></tr>
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<tr><td><br/></td></tr>
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</table>
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<table border="0" cellspacing="0" cellpadding="2" width="100%">
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<tr><td bgcolor="#525D76">
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<font color="#ffffff" face="arial,helvetica,sanserif">
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<a name="When to contact the Author"><strong>When to contact the Author</strong></a>
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</font>
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</td></tr>
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<tr><td>
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<blockquote>
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<p>
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Please resist the urge to contact the authors of this document (without bribes of fame and fortune attached). First
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contact the <a href="http://jakarta.apache.org/site/mail.html">mailing lists</a>. That being said feedback,
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and modifications to this document and samples are ever so greatly appreciatedThey are just best sent to the
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lists so that everyone can share in them. Certainly you'll get the most help there as well.
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Thanks for understanding.
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</p>
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</blockquote>
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</p>
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</td></tr>
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<tr><td><br/></td></tr>
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</table>
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</td>
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</tr>
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<!-- FOOTER -->
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<tr><td colspan="2">
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<hr noshade="" size="1"/>
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</td></tr>
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<tr><td colspan="2">
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<div align="center"><font color="#525D76" size="-1"><em>
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Copyright © 1999-2002, Apache Software Foundation
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</em></font></div>
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</td></tr>
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</table>
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</body>
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</html>
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<!-- end the processing -->
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