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diff --git a/docs/manual/introduction.html b/docs/manual/introduction.html index cdab330..3f18114 100644 --- a/docs/manual/introduction.html +++ b/docs/manual/introduction.html @@ -1,10 +1,21 @@ -<!doctype html PUBLIC "-//W3C//DTD HTML 3.2 Final//EN"> +<!doctype html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> <head> <meta http-equiv="content-type" content="text/html; charset=iso-8859-1"> <meta http-equiv="content-style-type" content="text/css"> <link rel="stylesheet" type="text/css" href="style.css"> <title>ProGuard Introduction</title> +<script type="text/javascript" language="JavaScript"> +<!-- +if (window.self==window.top) + window.top.location.replace("../index.html#"+window.location.pathname+window.location.hash); +else { + var hash="#"+window.location.pathname.replace(window.top.location.pathname.replace("index.html", ""), ""); + if (window.top.location.hash!=hash) + window.top.location.hash=hash; +} +//--> +</script> </head> <body> @@ -17,8 +28,7 @@ bytecode of the methods. The obfuscation step renames the remaining classes, fields, and methods using short meaningless names. These first steps make the code base smaller, more efficient, and harder to reverse-engineer. The final preverification step adds preverification information to the classes, which is -required for Java Micro Edition or which improves the start-up time for Java -6. +required for Java Micro Edition and for Java 6 and higher. <p> Each of these steps is optional. For instance, ProGuard can also be used to just list dead code in an application, or to preverify class files for @@ -62,13 +72,13 @@ efficient use in Java 6. </table> <p> -ProGuard typically reads the <b>input jars</b> (or wars, ears, zips, or -directories). It then shrinks, optimizes, obfuscates, and preverifies them. -Optionally, multiple optimization passes can be performed, each typically -followed by another shrinking step. ProGuard writes the processed results to -one or more <b>output jars</b> (or wars, ears, zips, or directories). The -input may contain resource files, whose names and contents can optionally be -updated to reflect the obfuscated class names. +ProGuard first reads the <b>input jars</b> (or wars, ears, zips, or +directories). It then subsequently shrinks, optimizes, obfuscates, and +preverifies them. You can optionally let ProGuard perform multiple +optimization passes. ProGuard writes the processed results to one or +more <b>output jars</b> (or wars, ears, zips, or directories). The input may +contain resource files, whose names and contents can optionally be updated to +reflect the obfuscated class names. <p> ProGuard requires the <b>library jars</b> (or wars, ears, zips, or directories) of the input jars to be specified. These are essentially the @@ -76,63 +86,69 @@ libraries that you would need for compiling the code. ProGuard uses them to reconstruct the class dependencies that are necessary for proper processing. The library jars themselves always remain unchanged. You should still put them in the class path of your final application. -<p> + +<h3>Entry points</h3> + In order to determine which code has to be preserved and which code can be discarded or obfuscated, you have to specify one or more <i>entry points</i> to your code. These entry points are typically classes with main methods, applets, -midlets, etc. +midlets, activities, etc. <ul> <li>In the <b>shrinking step</b>, ProGuard starts from these seeds and recursively determines which classes and class members are used. All other - classes and class members are discarded. + classes and class members are discarded.</li> <li>In the <b>optimization step</b>, ProGuard further optimizes the code. Among other optimizations, classes and methods that are not entry points can be made private, static, or final, unused parameters can be removed, - and some methods may be inlined. + and some methods may be inlined.</li> <li>In the <b>obfuscation step</b>, ProGuard renames classes and class members that are not entry points. In this entire process, keeping the entry - points ensures that they can still be accessed by their original names. + points ensures that they can still be accessed by their original names.</li> <li>The <b>preverification step</b> is the only step that doesn't have to know - the entry points. + the entry points.</li> </ul> <p> The <a href="usage.html">Usage section</a> of this manual describes the necessary <a href="usage.html#keepoptions"><code>-keep</code> options</a> and the <a href="examples.html">Examples section</a> provides plenty of examples. -<h3>Introspection</h3> - -Introspection presents particular problems for any automatic processing of -code. In ProGuard, classes or class members in your code that are created or -invoked dynamically (that is, by name) have to be specified as entry points -too. For example, <code>Class.forName()</code> constructs may refer to any -class at run-time. It is generally impossible to foresee which classes have to -be preserved (with their original names), since the class names might be read -from a configuration file, for instance. You therefore have to specify them in -your ProGuard configuration, with the same simple <code>-keep</code> options. +<h3>Reflection</h3> + +Reflection and introspection present particular problems for any automatic +processing of code. In ProGuard, classes or class members in your code that +are created or invoked dynamically (that is, by name) have to be specified as +entry points too. For example, <code>Class.forName()</code> constructs may +refer to any class at run-time. It is generally impossible to compute which +classes have to be preserved (with their original names), since the class +names might be read from a configuration file, for instance. You therefore +have to specify them in your ProGuard configuration, with the same +simple <code>-keep</code> options. <p> However, ProGuard will already detect and handle the following cases for you: <ul> -<li><code>Class.forName("SomeClass")</code> -<li><code>SomeClass.class</code> -<li><code>SomeClass.class.getField("someField")</code> -<li><code>SomeClass.class.getDeclaredField("someField")</code> -<li><code>SomeClass.class.getMethod("someMethod", new Class[] {})</code> -<li><code>SomeClass.class.getMethod("someMethod", new Class[] { A.class })</code> -<li><code>SomeClass.class.getMethod("someMethod", new Class[] { A.class, B.class })</code> -<li><code>SomeClass.class.getDeclaredMethod("someMethod", new Class[] {})</code> -<li><code>SomeClass.class.getDeclaredMethod("someMethod", new Class[] { A.class })</code> -<li><code>SomeClass.class.getDeclaredMethod("someMethod", new Class[] { A.class, B.class })</code> +<li><code>Class.forName("SomeClass")</code></li> +<li><code>SomeClass.class</code></li> +<li><code>SomeClass.class.getField("someField")</code></li> +<li><code>SomeClass.class.getDeclaredField("someField")</code></li> +<li><code>SomeClass.class.getMethod("someMethod", new Class[] {})</code></li> +<li><code>SomeClass.class.getMethod("someMethod", new Class[] { A.class })</code></li> +<li><code>SomeClass.class.getMethod("someMethod", new Class[] { A.class, B.class })</code></li> +<li><code>SomeClass.class.getDeclaredMethod("someMethod", new Class[] {})</code></li> +<li><code>SomeClass.class.getDeclaredMethod("someMethod", new Class[] { A.class })</code></li> +<li><code>SomeClass.class.getDeclaredMethod("someMethod", new Class[] { A.class, B.class })</code></li> +<li><code>AtomicIntegerFieldUpdater.newUpdater(SomeClass.class, "someField")</code></li> +<li><code>AtomicLongFieldUpdater.newUpdater(SomeClass.class, "someField")</code></li> +<li><code>AtomicReferenceFieldUpdater.newUpdater(SomeClass.class, SomeType.class, "someField")</code></li> </ul> The names of the classes and class members may of course be different, but the constructs should be literally the same for ProGuard to recognize them. The referenced classes and class members are preserved in the shrinking phase, and -the string arguments are properly replaced in the obfuscation phase. +the string arguments are properly updated in the obfuscation phase. <p> Furthermore, ProGuard will offer some suggestions if keeping some classes or class members appears necessary. For example, ProGuard will note constructs @@ -142,15 +158,15 @@ and/or its implementations may need to be preserved. You can then adapt your configuration accordingly. <p> For proper results, you should at least be somewhat familiar with the code -that you are processing. Obfuscating code that performs a lot of introspection +that you are processing. Obfuscating code that performs a lot of reflection may require trial and error, especially without the necessary information about the internals of the code. -<p> -<hr> +<hr /> +<noscript><div><a target="_top" href="../index.html" class="button">Show menu</a></div></noscript> <address> -Copyright © 2002-2009 -<a href="http://www.graphics.cornell.edu/~eric/">Eric Lafortune</a>. +Copyright © 2002-2013 +<a target="other" href="http://www.lafortune.eu/">Eric Lafortune</a>. </address> </body> </html> |