mirror of https://github.com/apache/lucene.git
LUCENE-4007: move demo to overview, so we can fix all broken links / outdated stuff
git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1328756 13f79535-47bb-0310-9956-ffa450edef68
This commit is contained in:
Robert Muir
parent
0c8cbf2d14
commit
51b99daad0
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@ -15,12 +15,204 @@
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limitations under the License.
|
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-->
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<html>
|
||||
<head>
|
||||
<title>
|
||||
demo
|
||||
</title>
|
||||
</head>
|
||||
<body>
|
||||
demo
|
||||
</body>
|
||||
<head>
|
||||
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
|
||||
<title>Apache Lucene - Building and Installing the Basic Demo</title>
|
||||
</head>
|
||||
<body>
|
||||
<h1>Apache Lucene - Building and Installing the Basic Demo</h1>
|
||||
<div id="minitoc-area">
|
||||
<ul class="minitoc">
|
||||
<li><a href="#About%20this%20Document">About this Document</a></li>
|
||||
<li><a href="#About%20the%20Demo">About the Demo</a></li>
|
||||
<li><a href="#Setting%20your%20CLASSPATH">Setting your CLASSPATH</a></li>
|
||||
<li><a href="#Indexing%20Files">Indexing Files</a></li>
|
||||
<li><a href="#About%20the%20code">About the code</a></li>
|
||||
<li><a href="#Location%20of%20the%20source">Location of the source</a></li>
|
||||
<li><a href="#IndexFiles">IndexFiles</a></li>
|
||||
<li><a href="#Searching%20Files">Searching Files</a></li>
|
||||
</ul>
|
||||
</div>
|
||||
<a name="N10013" id="N10013"></a><a name="About this Document"></a>
|
||||
<h2 class="boxed">About this Document</h2>
|
||||
<div class="section">
|
||||
<p>This document is intended as a "getting started" guide to using and running
|
||||
the Lucene demos. It walks you through some basic installation and
|
||||
configuration.</p>
|
||||
</div>
|
||||
<a name="N1001C" id="N1001C"></a><a name="About the Demo"></a>
|
||||
<h2 class="boxed">About the Demo</h2>
|
||||
<div class="section">
|
||||
<p>The Lucene command-line demo code consists of an application that
|
||||
demonstrates various functionalities of Lucene and how you can add Lucene to
|
||||
your applications.</p>
|
||||
</div>
|
||||
<a name="N10025" id="N10025"></a><a name="Setting your CLASSPATH"></a>
|
||||
<h2 class="boxed">Setting your CLASSPATH</h2>
|
||||
<div class="section">
|
||||
<p>First, you should <a href=
|
||||
"http://www.apache.org/dyn/closer.cgi/lucene/java/">download</a> the latest
|
||||
Lucene distribution and then extract it to a working directory.</p>
|
||||
<p>You need three JARs: the Lucene JAR, the common analysis JAR, and the Lucene
|
||||
demo JAR. You should see the Lucene JAR file in the core/ directory you created
|
||||
when you extracted the archive -- it should be named something like
|
||||
<span class="codefrag">lucene-core-{version}.jar</span>. You should also see
|
||||
files called <span class=
|
||||
"codefrag">lucene-analyzers-common-{version}.jar</span> and <span class=
|
||||
"codefrag">lucene-demo-{version}.jar</span> under analysis/common/ and demo/,
|
||||
respectively.</p>
|
||||
<p>Put all three of these files in your Java CLASSPATH.</p>
|
||||
</div>
|
||||
<a name="N10041" id="N10041"></a><a name="Indexing Files"></a>
|
||||
<h2 class="boxed">Indexing Files</h2>
|
||||
<div class="section">
|
||||
<p>Once you've gotten this far you're probably itching to go. Let's <b>build an
|
||||
index!</b> Assuming you've set your CLASSPATH correctly, just type:</p>
|
||||
<pre>
|
||||
java org.apache.lucene.demo.IndexFiles -docs {path-to-lucene}/src
|
||||
</pre>
|
||||
This will produce a subdirectory called <span class="codefrag">index</span>
|
||||
which will contain an index of all of the Lucene source code.
|
||||
<p>To <b>search the index</b> type:</p>
|
||||
<pre>
|
||||
java org.apache.lucene.demo.SearchFiles
|
||||
</pre>
|
||||
You'll be prompted for a query. Type in a swear word and press the enter key.
|
||||
You'll see that the Lucene developers are very well mannered and get no
|
||||
results. Now try entering the word "string". That should return a whole bunch
|
||||
of documents. The results will page at every tenth result and ask you whether
|
||||
you want more results.</div>
|
||||
<a name="N10013" id="N10013"></a><a name="About the Code"></a>
|
||||
<h2 class="boxed">About the Code</h2>
|
||||
<div class="section">
|
||||
<p>In this section we walk through the sources behind the command-line Lucene
|
||||
demo: where to find them, their parts and their function. This section is
|
||||
intended for Java developers wishing to understand how to use Lucene in their
|
||||
applications.</p>
|
||||
</div>
|
||||
<a name="N1001C" id="N1001C"></a><a name="Location of the source"></a>
|
||||
<h2 class="boxed">Location of the source</h2>
|
||||
<div class="section">
|
||||
<p>NOTE: to examine the sources, you need to download and extract a source
|
||||
checkout of Lucene: (lucene-{version}-src.zip).</p>
|
||||
<p>Relative to the directory created when you extracted Lucene, you should see
|
||||
a directory called <span class="codefrag">lucene/demo/</span>. This is the root
|
||||
for the Lucene demo. Under this directory is <span class=
|
||||
"codefrag">src/java/org/apache/lucene/demo/</span>. This is where all the Java
|
||||
sources for the demo live.</p>
|
||||
<p>Within this directory you should see the <span class=
|
||||
"codefrag">IndexFiles.java</span> class we executed earlier. Bring it up in
|
||||
<span class="codefrag">vi</span> or your editor of choice and let's take a look
|
||||
at it.</p>
|
||||
</div>
|
||||
<a name="N10037" id="N10037"></a><a name="IndexFiles" id="IndexFiles"></a>
|
||||
<h2 class="boxed">IndexFiles</h2>
|
||||
<div class="section">
|
||||
<p>As we discussed in the previous walk-through, the <a href=
|
||||
"api/demo/org/apache/lucene/demo/IndexFiles.html">IndexFiles</a> class creates
|
||||
a Lucene Index. Let's take a look at how it does this.</p>
|
||||
<p>The <span class="codefrag">main()</span> method parses the command-line
|
||||
parameters, then in preparation for instantiating <a href=
|
||||
"api/core/org/apache/lucene/index/IndexWriter.html">IndexWriter</a>, opens a
|
||||
<a href="api/core/org/apache/lucene/store/Directory.html">Directory</a> and
|
||||
instantiates <a href=
|
||||
"api/analyzers-common/org/apache/lucene/analysis/standard/StandardAnalyzer.html">
|
||||
StandardAnalyzer</a> and <a href=
|
||||
"api/core/org/apache/lucene/index/IndexWriterConfig.html">IndexWriterConfig</a>.</p>
|
||||
<p>The value of the <span class="codefrag">-index</span> command-line parameter
|
||||
is the name of the filesystem directory where all index information should be
|
||||
stored. If <span class="codefrag">IndexFiles</span> is invoked with a relative
|
||||
path given in the <span class="codefrag">-index</span> command-line parameter,
|
||||
or if the <span class="codefrag">-index</span> command-line parameter is not
|
||||
given, causing the default relative index path "<span class=
|
||||
"codefrag">index</span>" to be used, the index path will be created as a
|
||||
subdirectory of the current working directory (if it does not already exist).
|
||||
On some platforms, the index path may be created in a different directory (such
|
||||
as the user's home directory).</p>
|
||||
<p>The <span class="codefrag">-docs</span> command-line parameter value is the
|
||||
location of the directory containing files to be indexed.</p>
|
||||
<p>The <span class="codefrag">-update</span> command-line parameter tells
|
||||
<span class="codefrag">IndexFiles</span> not to delete the index if it already
|
||||
exists. When <span class="codefrag">-update</span> is not given, <span class=
|
||||
"codefrag">IndexFiles</span> will first wipe the slate clean before indexing
|
||||
any documents.</p>
|
||||
<p>Lucene <a href=
|
||||
"api/core/org/apache/lucene/store/Directory.html">Directory</a>s are used by
|
||||
the <span class="codefrag">IndexWriter</span> to store information in the
|
||||
index. In addition to the <a href=
|
||||
"api/core/org/apache/lucene/store/FSDirectory.html">FSDirectory</a>
|
||||
implementation we are using, there are several other <span class=
|
||||
"codefrag">Directory</span> subclasses that can write to RAM, to databases,
|
||||
etc.</p>
|
||||
<p>Lucene <a href=
|
||||
"api/core/org/apache/lucene/analysis/Analyzer.html">Analyzer</a>s are
|
||||
processing pipelines that break up text into indexed tokens, a.k.a. terms, and
|
||||
optionally perform other operations on these tokens, e.g. downcasing, synonym
|
||||
insertion, filtering out unwanted tokens, etc. The <span class=
|
||||
"codefrag">Analyzer</span> we are using is <span class=
|
||||
"codefrag">StandardAnalyzer</span>, which creates tokens using the Word Break
|
||||
rules from the Unicode Text Segmentation algorithm specified in <a href=
|
||||
"http://unicode.org/reports/tr29/">Unicode Standard Annex #29</a>; converts
|
||||
tokens to lowercase; and then filters out stopwords. Stopwords are common
|
||||
language words such as articles (a, an, the, etc.) and other tokens that may
|
||||
have less value for searching. It should be noted that there are different
|
||||
rules for every language, and you should use the proper analyzer for each.
|
||||
Lucene currently provides Analyzers for a number of different languages (see
|
||||
the javadocs under <a href=
|
||||
"api/analyzers-common/org/apache/lucene/analysis/">lucene/analysis/common/src/java/org/apache/lucene/analysis</a>).</p>
|
||||
<p>The <span class="codefrag">IndexWriterConfig</span> instance holds all
|
||||
configuration for <span class="codefrag">IndexWriter</span>. For example, we
|
||||
set the <span class="codefrag">OpenMode</span> to use here based on the value
|
||||
of the <span class="codefrag">-update</span> command-line parameter.</p>
|
||||
<p>Looking further down in the file, after <span class=
|
||||
"codefrag">IndexWriter</span> is instantiated, you should see the <span class=
|
||||
"codefrag">indexDocs()</span> code. This recursive function crawls the
|
||||
directories and creates <a href=
|
||||
"api/core/org/apache/lucene/document/Document.html">Document</a> objects. The
|
||||
<span class="codefrag">Document</span> is simply a data object to represent the
|
||||
text content from the file as well as its creation time and location. These
|
||||
instances are added to the <span class="codefrag">IndexWriter</span>. If the
|
||||
<span class="codefrag">-update</span> command-line parameter is given, the
|
||||
<span class="codefrag">IndexWriter</span> <span class=
|
||||
"codefrag">OpenMode</span> will be set to <span class=
|
||||
"codefrag">OpenMode.CREATE_OR_APPEND</span>, and rather than adding documents
|
||||
to the index, the <span class="codefrag">IndexWriter</span> will
|
||||
<strong>update</strong> them in the index by attempting to find an
|
||||
already-indexed document with the same identifier (in our case, the file path
|
||||
serves as the identifier); deleting it from the index if it exists; and then
|
||||
adding the new document to the index.</p>
|
||||
</div>
|
||||
<a name="N100DB" id="N100DB"></a><a name="Searching Files"></a>
|
||||
<h2 class="boxed">Searching Files</h2>
|
||||
<div class="section">
|
||||
<p>The <a href=
|
||||
"api/demo/org/apache/lucene/demo/SearchFiles.html">SearchFiles</a> class is
|
||||
quite simple. It primarily collaborates with an <a href=
|
||||
"api/core/org/apache/lucene/search/IndexSearcher.html">IndexSearcher</a>,
|
||||
<a href=
|
||||
"api/analyzers-common/org/apache/lucene/analysis/standard/StandardAnalyzer.html">
|
||||
StandardAnalyzer</a> (which is used in the <a href=
|
||||
"api/demo/org/apache/lucene/demo/IndexFiles.html">IndexFiles</a> class as well)
|
||||
and a <a href=
|
||||
"api/core/org/apache/lucene/queryParser/QueryParser.html">QueryParser</a>. The
|
||||
query parser is constructed with an analyzer used to interpret your query text
|
||||
in the same way the documents are interpreted: finding word boundaries,
|
||||
downcasing, and removing useless words like 'a', 'an' and 'the'. The <a href=
|
||||
"api/core/org/apache/lucene/search/Query.html">Query</a> object contains the
|
||||
results from the <a href=
|
||||
"api/core/org/apache/lucene/queryParser/QueryParser.html">QueryParser</a> which
|
||||
is passed to the searcher. Note that it's also possible to programmatically
|
||||
construct a rich <a href=
|
||||
"api/core/org/apache/lucene/search/Query.html">Query</a> object without using
|
||||
the query parser. The query parser just enables decoding the <a href=
|
||||
"queryparsersyntax.html">Lucene query syntax</a> into the corresponding
|
||||
<a href="api/core/org/apache/lucene/search/Query.html">Query</a> object.</p>
|
||||
<p><span class="codefrag">SearchFiles</span> uses the <span class=
|
||||
"codefrag">IndexSearcher.search(query,n)</span> method that returns <a href=
|
||||
"api/core/org/apache/lucene/search/TopDocs.html">TopDocs</a> with max
|
||||
<span class="codefrag">n</span> hits. The results are printed in pages, sorted
|
||||
by score (i.e. relevance).</p>
|
||||
</div>
|
||||
</body>
|
||||
</html>
|
||||
|
||||
|
|
|
|||
|
|
@ -1,72 +0,0 @@
|
|||
<html>
|
||||
<head>
|
||||
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
|
||||
<title>Apache Lucene - Building and Installing the Basic Demo</title>
|
||||
</head>
|
||||
<body>
|
||||
<h1>Apache Lucene - Building and Installing the Basic Demo</h1>
|
||||
<div id="minitoc-area">
|
||||
<ul class="minitoc">
|
||||
<li><a href="#About%20this%20Document">About this Document</a></li>
|
||||
<li><a href="#About%20the%20Demo">About the Demo</a></li>
|
||||
<li><a href="#Setting%20your%20CLASSPATH">Setting your CLASSPATH</a></li>
|
||||
<li><a href="#Indexing%20Files">Indexing Files</a></li>
|
||||
<li><a href="#About%20the%20code...">About the code...</a></li>
|
||||
</ul>
|
||||
</div>
|
||||
<a name="N10013" id="N10013"></a><a name="About this Document"></a>
|
||||
<h2 class="boxed">About this Document</h2>
|
||||
<div class="section">
|
||||
<p>This document is intended as a "getting started" guide to using and running
|
||||
the Lucene demos. It walks you through some basic installation and
|
||||
configuration.</p>
|
||||
</div>
|
||||
<a name="N1001C" id="N1001C"></a><a name="About the Demo"></a>
|
||||
<h2 class="boxed">About the Demo</h2>
|
||||
<div class="section">
|
||||
<p>The Lucene command-line demo code consists of an application that
|
||||
demonstrates various functionalities of Lucene and how you can add Lucene to
|
||||
your applications.</p>
|
||||
</div>
|
||||
<a name="N10025" id="N10025"></a><a name="Setting your CLASSPATH"></a>
|
||||
<h2 class="boxed">Setting your CLASSPATH</h2>
|
||||
<div class="section">
|
||||
<p>First, you should <a href=
|
||||
"http://www.apache.org/dyn/closer.cgi/lucene/java/">download</a> the latest
|
||||
Lucene distribution and then extract it to a working directory.</p>
|
||||
<p>You need three JARs: the Lucene JAR, the common analysis JAR, and the Lucene
|
||||
demo JAR. You should see the Lucene JAR file in the core/ directory you created
|
||||
when you extracted the archive -- it should be named something like
|
||||
<span class="codefrag">lucene-core-{version}.jar</span>. You should also see
|
||||
files called <span class=
|
||||
"codefrag">lucene-analyzers-common-{version}.jar</span> and <span class=
|
||||
"codefrag">lucene-demo-{version}.jar</span> under analysis/common/ and demo/,
|
||||
respectively.</p>
|
||||
<p>Put all three of these files in your Java CLASSPATH.</p>
|
||||
</div>
|
||||
<a name="N10041" id="N10041"></a><a name="Indexing Files"></a>
|
||||
<h2 class="boxed">Indexing Files</h2>
|
||||
<div class="section">
|
||||
<p>Once you've gotten this far you're probably itching to go. Let's <b>build an
|
||||
index!</b> Assuming you've set your CLASSPATH correctly, just type:</p>
|
||||
<pre>
|
||||
java org.apache.lucene.demo.IndexFiles -docs {path-to-lucene}/src
|
||||
</pre>
|
||||
This will produce a subdirectory called <span class="codefrag">index</span>
|
||||
which will contain an index of all of the Lucene source code.
|
||||
<p>To <b>search the index</b> type:</p>
|
||||
<pre>
|
||||
java org.apache.lucene.demo.SearchFiles
|
||||
</pre>
|
||||
You'll be prompted for a query. Type in a swear word and press the enter key.
|
||||
You'll see that the Lucene developers are very well mannered and get no
|
||||
results. Now try entering the word "string". That should return a whole bunch
|
||||
of documents. The results will page at every tenth result and ask you whether
|
||||
you want more results.</div>
|
||||
<a name="N1005C" id="N1005C"></a><a name="About the code..."></a>
|
||||
<h2 class="boxed">About the code...</h2>
|
||||
<div class="section">
|
||||
<p><a href="demo2.html">read on>>></a></p>
|
||||
</div>
|
||||
</body>
|
||||
</html>
|
||||
|
|
@ -1,148 +0,0 @@
|
|||
<html>
|
||||
<head>
|
||||
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
|
||||
<title>Apache Lucene - Basic Demo Sources Walk-through</title>
|
||||
</head>
|
||||
<body>
|
||||
<h1>Apache Lucene - Basic Demo Sources Walk-through</h1>
|
||||
<div id="minitoc-area">
|
||||
<ul class="minitoc">
|
||||
<li><a href="#About%20the%20Code">About the Code</a></li>
|
||||
<li><a href="#Location%20of%20the%20source">Location of the source</a></li>
|
||||
<li><a href="#IndexFiles">IndexFiles</a></li>
|
||||
<li><a href="#Searching%20Files">Searching Files</a></li>
|
||||
</ul>
|
||||
</div>
|
||||
<a name="N10013" id="N10013"></a><a name="About the Code"></a>
|
||||
<h2 class="boxed">About the Code</h2>
|
||||
<div class="section">
|
||||
<p>In this section we walk through the sources behind the command-line Lucene
|
||||
demo: where to find them, their parts and their function. This section is
|
||||
intended for Java developers wishing to understand how to use Lucene in their
|
||||
applications.</p>
|
||||
</div>
|
||||
<a name="N1001C" id="N1001C"></a><a name="Location of the source"></a>
|
||||
<h2 class="boxed">Location of the source</h2>
|
||||
<div class="section">
|
||||
<p>NOTE: to examine the sources, you need to download and extract a source
|
||||
checkout of Lucene: (lucene-{version}-src.zip).</p>
|
||||
<p>Relative to the directory created when you extracted Lucene, you should see
|
||||
a directory called <span class="codefrag">lucene/demo/</span>. This is the root
|
||||
for the Lucene demo. Under this directory is <span class=
|
||||
"codefrag">src/java/org/apache/lucene/demo/</span>. This is where all the Java
|
||||
sources for the demo live.</p>
|
||||
<p>Within this directory you should see the <span class=
|
||||
"codefrag">IndexFiles.java</span> class we executed earlier. Bring it up in
|
||||
<span class="codefrag">vi</span> or your editor of choice and let's take a look
|
||||
at it.</p>
|
||||
</div>
|
||||
<a name="N10037" id="N10037"></a><a name="IndexFiles" id="IndexFiles"></a>
|
||||
<h2 class="boxed">IndexFiles</h2>
|
||||
<div class="section">
|
||||
<p>As we discussed in the previous walk-through, the <a href=
|
||||
"api/demo/org/apache/lucene/demo/IndexFiles.html">IndexFiles</a> class creates
|
||||
a Lucene Index. Let's take a look at how it does this.</p>
|
||||
<p>The <span class="codefrag">main()</span> method parses the command-line
|
||||
parameters, then in preparation for instantiating <a href=
|
||||
"api/core/org/apache/lucene/index/IndexWriter.html">IndexWriter</a>, opens a
|
||||
<a href="api/core/org/apache/lucene/store/Directory.html">Directory</a> and
|
||||
instantiates <a href=
|
||||
"api/analyzers-common/org/apache/lucene/analysis/standard/StandardAnalyzer.html">
|
||||
StandardAnalyzer</a> and <a href=
|
||||
"api/core/org/apache/lucene/index/IndexWriterConfig.html">IndexWriterConfig</a>.</p>
|
||||
<p>The value of the <span class="codefrag">-index</span> command-line parameter
|
||||
is the name of the filesystem directory where all index information should be
|
||||
stored. If <span class="codefrag">IndexFiles</span> is invoked with a relative
|
||||
path given in the <span class="codefrag">-index</span> command-line parameter,
|
||||
or if the <span class="codefrag">-index</span> command-line parameter is not
|
||||
given, causing the default relative index path "<span class=
|
||||
"codefrag">index</span>" to be used, the index path will be created as a
|
||||
subdirectory of the current working directory (if it does not already exist).
|
||||
On some platforms, the index path may be created in a different directory (such
|
||||
as the user's home directory).</p>
|
||||
<p>The <span class="codefrag">-docs</span> command-line parameter value is the
|
||||
location of the directory containing files to be indexed.</p>
|
||||
<p>The <span class="codefrag">-update</span> command-line parameter tells
|
||||
<span class="codefrag">IndexFiles</span> not to delete the index if it already
|
||||
exists. When <span class="codefrag">-update</span> is not given, <span class=
|
||||
"codefrag">IndexFiles</span> will first wipe the slate clean before indexing
|
||||
any documents.</p>
|
||||
<p>Lucene <a href=
|
||||
"api/core/org/apache/lucene/store/Directory.html">Directory</a>s are used by
|
||||
the <span class="codefrag">IndexWriter</span> to store information in the
|
||||
index. In addition to the <a href=
|
||||
"api/core/org/apache/lucene/store/FSDirectory.html">FSDirectory</a>
|
||||
implementation we are using, there are several other <span class=
|
||||
"codefrag">Directory</span> subclasses that can write to RAM, to databases,
|
||||
etc.</p>
|
||||
<p>Lucene <a href=
|
||||
"api/core/org/apache/lucene/analysis/Analyzer.html">Analyzer</a>s are
|
||||
processing pipelines that break up text into indexed tokens, a.k.a. terms, and
|
||||
optionally perform other operations on these tokens, e.g. downcasing, synonym
|
||||
insertion, filtering out unwanted tokens, etc. The <span class=
|
||||
"codefrag">Analyzer</span> we are using is <span class=
|
||||
"codefrag">StandardAnalyzer</span>, which creates tokens using the Word Break
|
||||
rules from the Unicode Text Segmentation algorithm specified in <a href=
|
||||
"http://unicode.org/reports/tr29/">Unicode Standard Annex #29</a>; converts
|
||||
tokens to lowercase; and then filters out stopwords. Stopwords are common
|
||||
language words such as articles (a, an, the, etc.) and other tokens that may
|
||||
have less value for searching. It should be noted that there are different
|
||||
rules for every language, and you should use the proper analyzer for each.
|
||||
Lucene currently provides Analyzers for a number of different languages (see
|
||||
the javadocs under <a href=
|
||||
"api/analyzers-common/org/apache/lucene/analysis/">lucene/analysis/common/src/java/org/apache/lucene/analysis</a>).</p>
|
||||
<p>The <span class="codefrag">IndexWriterConfig</span> instance holds all
|
||||
configuration for <span class="codefrag">IndexWriter</span>. For example, we
|
||||
set the <span class="codefrag">OpenMode</span> to use here based on the value
|
||||
of the <span class="codefrag">-update</span> command-line parameter.</p>
|
||||
<p>Looking further down in the file, after <span class=
|
||||
"codefrag">IndexWriter</span> is instantiated, you should see the <span class=
|
||||
"codefrag">indexDocs()</span> code. This recursive function crawls the
|
||||
directories and creates <a href=
|
||||
"api/core/org/apache/lucene/document/Document.html">Document</a> objects. The
|
||||
<span class="codefrag">Document</span> is simply a data object to represent the
|
||||
text content from the file as well as its creation time and location. These
|
||||
instances are added to the <span class="codefrag">IndexWriter</span>. If the
|
||||
<span class="codefrag">-update</span> command-line parameter is given, the
|
||||
<span class="codefrag">IndexWriter</span> <span class=
|
||||
"codefrag">OpenMode</span> will be set to <span class=
|
||||
"codefrag">OpenMode.CREATE_OR_APPEND</span>, and rather than adding documents
|
||||
to the index, the <span class="codefrag">IndexWriter</span> will
|
||||
<strong>update</strong> them in the index by attempting to find an
|
||||
already-indexed document with the same identifier (in our case, the file path
|
||||
serves as the identifier); deleting it from the index if it exists; and then
|
||||
adding the new document to the index.</p>
|
||||
</div>
|
||||
<a name="N100DB" id="N100DB"></a><a name="Searching Files"></a>
|
||||
<h2 class="boxed">Searching Files</h2>
|
||||
<div class="section">
|
||||
<p>The <a href=
|
||||
"api/demo/org/apache/lucene/demo/SearchFiles.html">SearchFiles</a> class is
|
||||
quite simple. It primarily collaborates with an <a href=
|
||||
"api/core/org/apache/lucene/search/IndexSearcher.html">IndexSearcher</a>,
|
||||
<a href=
|
||||
"api/analyzers-common/org/apache/lucene/analysis/standard/StandardAnalyzer.html">
|
||||
StandardAnalyzer</a> (which is used in the <a href=
|
||||
"api/demo/org/apache/lucene/demo/IndexFiles.html">IndexFiles</a> class as well)
|
||||
and a <a href=
|
||||
"api/core/org/apache/lucene/queryParser/QueryParser.html">QueryParser</a>. The
|
||||
query parser is constructed with an analyzer used to interpret your query text
|
||||
in the same way the documents are interpreted: finding word boundaries,
|
||||
downcasing, and removing useless words like 'a', 'an' and 'the'. The <a href=
|
||||
"api/core/org/apache/lucene/search/Query.html">Query</a> object contains the
|
||||
results from the <a href=
|
||||
"api/core/org/apache/lucene/queryParser/QueryParser.html">QueryParser</a> which
|
||||
is passed to the searcher. Note that it's also possible to programmatically
|
||||
construct a rich <a href=
|
||||
"api/core/org/apache/lucene/search/Query.html">Query</a> object without using
|
||||
the query parser. The query parser just enables decoding the <a href=
|
||||
"queryparsersyntax.html">Lucene query syntax</a> into the corresponding
|
||||
<a href="api/core/org/apache/lucene/search/Query.html">Query</a> object.</p>
|
||||
<p><span class="codefrag">SearchFiles</span> uses the <span class=
|
||||
"codefrag">IndexSearcher.search(query,n)</span> method that returns <a href=
|
||||
"api/core/org/apache/lucene/search/TopDocs.html">TopDocs</a> with max
|
||||
<span class="codefrag">n</span> hits. The results are printed in pages, sorted
|
||||
by score (i.e. relevance).</p>
|
||||
</div>
|
||||
</body>
|
||||
</html>
|
||||
|
|
@ -54,13 +54,9 @@
|
|||
<p>Each section listed below builds on one another. More advanced users may
|
||||
wish to skip sections.</p>
|
||||
<ul>
|
||||
<li><a href="demo.html">About the command-line Lucene demo and its usage</a>.
|
||||
<li><a href="demo/overview-summary.html#overview_description">About the command-line Lucene demo, its usage, and sources</a>.
|
||||
This section is intended for anyone who wants to use the command-line Lucene
|
||||
demo.</li>
|
||||
<li><a href="demo2.html">About the sources and implementation for the
|
||||
command-line Lucene demo</a>. This section walks through the implementation
|
||||
details (sources) of the command-line Lucene demo. This section is intended for
|
||||
developers.</li>
|
||||
demo, and provides a walk through the source code.</li>
|
||||
</ul>
|
||||
<h2>Javadocs</h2>
|
||||
<xsl:call-template name="modules"/>
|
||||
|
|
|
|||
Loading…
Reference in New Issue