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      <h1 class="project-name title-font">JavaParser</h1>
      <h2 class="project-tagline">Process Java code programmatically</h2>
    </section>

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        <li class="selected"><a href="index.html">Home</a></li>
        <li><a href="gettingstarted.html">Getting started</a>
        <li><a href="about.html">About</a>
        <li><a href="contributing.html">Contributing</a>
          <li><a href="presentations.html">Presentations</a>
        <li class="last"><a href="https://github.com/javaparser">on GitHub</a>  
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<p>
Our goal is to build a <b>simple</b> and <b>lightweight</b> set of tools
to generate, analyze, and process Java code.
</p>
<p>
All of this is offered under a business friendly <a href="#license">license</a>.
</p>

<p>
JavaParser is used in dozens of open-source and commercial projects.
Show your love adding one star more or spreading the word.
</p>

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      <h2 class="area-title">What you can do with JavaParser</h2>

<p>JavaParser is a set of tools to:
  <ul>
    <li><a href="#parse">parse</a>
    <li><a href="#analyze">analyze</a>
    <li><a href="#transform">transform</a>
    <li><a href="#generate">generate</a> 
  </ul>
  Java code.
</p>

<div class="box">
  <a href="https://leanpub.com/javaparservisited"><img src="images/javaparser-book.jpg" height="300px"/></a>
  <h2>Want to learn JavaParser?</h2>
    <p>
    We <b>are writing</b> <a href="https://leanpub.com/javaparservisited">a book</a> on JavaParser and we need <a href="https://github.com/javaparser/javaparser-visited/issues/new">your feedback</a>!
    </p>
    <p>
    Help us understanding what is not clear, what should we add, share examples and ideas with us.
    You can also contact us <a href="https://gitter.im/javaparser/javaparserbook">on gitter</a> or on the <a href="https://github.com/javaparser/javaparser-visited/issues/new">book repository</a>.
    </p>
    <p>
    It would be great if you could help us spread the word:
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Tweet!</a></p>
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<p>In the rest of the page we will look on different features of JavaParser. You may also be interested
in checking out some <a href="presentations.html">presentations</a> we gave about JavaParser.</p>

<a name="parse"></a>
<h3 class="subarea-title">Parsing Java code</h3>

<p>Using JavaParser you can get an Abstract Syntax Tree (AST) from Java code.
The AST is a structure representing your Java code in a way that it is easy to process:
</p>

<div class="highlight highlight-text-java"><pre class="prettyprint lang-java">
CompilationUnit compilationUnit = JavaParser.parse("class A { }");
Optional&lt;ClassOrInterfaceDeclaration> classA = compilationUnit.getClassByName("A");
</pre></div>

<a name="analyze"></a>
<h3 class="subarea-title">Analyze Java code</h3>

<p>Suppose you want to look for fields which are public and not static.
This is pretty easy using JavaParser:</p>

<div class="highlight highlight-text-java"><pre class="prettyprint lang-java">
compilationUnit.findAll(FieldDeclaration.class).stream()
        .filter(f -> f.isPublic() && !f.isStatic())
        .forEach(f -> System.out.println("Check field at line " +
            f.getRange().map(r -> r.begin.line).orElse(-1)));
</pre></div>

<a name="transform"></a>
<h3 class="subarea-title">Transform Java code</h3>

<p>Maybe you want to ensure all abstract classes have a name starting with <i>Abstract</i>:</p>

<div class="highlight highlight-text-java"><pre class="prettyprint lang-java">
compilationUnit.findAll(ClassOrInterfaceDeclaration.class).stream()
        .filter(c -> !c.isInterface()
                && c.isAbstract()
                && !c.getNameAsString().startsWith("Abstract"))
        .forEach(c -> {
            String oldName = c.getNameAsString();
            String newName = "Abstract" + oldName;
            System.out.println("Renaming class " + oldName + " into " + newName);
            c.setName(newName);
        });
</pre></div>

<a name="generate"></a>
<h3 class="subarea-title">Generate Java code</h3>

<div class="highlight highlight-text-java"><pre class="prettyprint lang-java">
CompilationUnit compilationUnit = new CompilationUnit();
ClassOrInterfaceDeclaration myClass = compilationUnit
        .addClass("MyClass")
        .setPublic(true);
myClass.addField(int.class, "A_CONSTANT", PUBLIC, STATIC);
myClass.addField(String.class, "name", PRIVATE);
String code = myClass.toString();
</pre></div>        

<h2 class="area-title">Components of JavaParser</h2>

JavaParser is both the name of the set of tools and of the main component: the parser.

In addition to JavaParser there is another component in the set of tools: <a href="https://github.com/javaparser/javasymbolsolver">JavaSymbolSolver</a>.

<p>The parser is extra lightweight (no dependencies at all!) and can give you super fast an AST for your Java code. Sometimes an AST is not enough because you want:</p>
<br>
<ul>
<li>Understand to which element a certain name refer: a field? A variable?
<li>You need to know the type of a complex expression
<li>You want to get a list of all the interfaces implemented (also indirectly) by a certain class
</ul>

JavaSymbolSolver does the extra work to answer this questions for you. 

<h2>
<a id="license" class="anchor" href="#license" aria-hidden="true"><span aria-hidden="true" class="octicon octicon-link"></span></a>License</h2>

<p>JavaParser is available either under the terms of the LGPL License or the Apache License. You as the user are entitled to choose the terms under which adopt JavaParser.</p>

<p>For details about the LGPL License please refer to LICENSE.LGPL.</p>

<p>For details about the Apache License please refer to LICENSE.APACHE.</p>

      <footer class="site-footer">
        <span class=""><a href="https://github.com/javaparser">JavaParser</a> is maintained by Open-Source enthusiasts.</span>

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