1<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" 2 "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"> 3 4<html> 5 6<head> 7 8<title>Dalvik Libraries</title> 9 10<link rel=stylesheet href="dex-format.css"> 11<link href="prettify.css" type="text/css" rel="stylesheet" /> 12<script type="text/javascript" src="prettify.js"></script> 13 14<style> 15ul.code li { 16 font-family: monospace; 17} 18</style> 19 20</head> 21 22<body onload="prettyPrint()"> 23 24<h1 class="title">Dalvik Libraries</h1> 25 26<p>The Dalvik Libraries, also known as the <i>Android core libraries</i>, 27implement general purpose APIs used by code written in the Java programming 28language. While the libraries themselves don't depend on Android, they do form 29the foundation of the Android framework. Android applications use the Dalvik 30libraries both directly and indirectly for data structures, networking, 31concurrency, I/O, and more.</p> 32 33<p>The Dalvik libraries break down into two categories:</p> 34 35<ul> 36 <li><a href="#vm-specific">Dalvik VM-specific libraries</a></li> 37 <li><a href="#interop">Java programming language interoperability 38 libraries</a></li> 39</ul> 40 41<p>Any system claiming to be Android-compatible must implement these libraries. 42Unless otherwise noted, both the signatures and the behavior of such a system 43need to conform to the Android 1.0 reference implementation. Both types of 44conformance will be checked by the upcoming Android Compatibility Test Suite 45(CTS).</p> 46 47<a name="vm-specific"/><h2>Dalvik VM-specific libraries</h2> 48 49<p>The VM-specific libraries enable requesting or modifying VM-specific 50information. Code that uses these classes is only portable across Dalvik-based 51systems. The VM-specific Dalvik packages include:</p> 52 53<ul class="code"> 54 <li>dalvik.annotation</li> 55 <li>dalvik.bytecode</li> 56 <li>dalvik.system</li> 57</ul> 58 59<a name="interop"/><h2>Java programming language interoperability libraries</h2> 60 61<p>This category of library provides a familiar environment for programmers 62writing code in the Java programming language. Much of the implementation of 63this code comes from <a href="http://harmony.apache.org/">Apache Harmony</a>. 64Sometimes, we have to change the Harmony code to make it more suitable for the 65memory and CPU-constrained environments targeted by Dalvik. We delineate 66Dalvik-specific changes like so: 67 68<pre class="prettyprint"> 69 private static final long serialVersionUID = 8683452581122892189L; 70 71// BEGIN android-added 72 /** zero-element array */ 73 private static final Object[] emptyArray = new Object[0]; 74// END android-added 75 76 private transient int firstIndex; 77</pre> 78 79<p>If you change existing Harmony code instead of just inserting new code, use 80<code>android-changed</code> instead of <code>android-added</code>. These 81markers help us keep track of our own changes when we pull down updates from 82Harmony.</p> 83 84<p>Packages in this category include:</p> 85 86<ul class="code"> 87 <li>java.io</li> 88 <li>java.lang</li> 89 <li>java.lang.annotation</li> 90 <li>java.lang.ref</li> 91 <li>java.lang.reflect</li> 92 <li>java.math</li> 93 <li>java.net</li> 94 <li>java.nio</li> 95 <li>java.nio.channels</li> 96 <li>java.nio.channels.spi</li> 97 <li>java.nio.charset</li> 98 <li>java.nio.charset.spi</li> 99 <li>java.security</li> 100 <li>java.security.acl</li> 101 <li>java.security.cert</li> 102 <li>java.security.interfaces</li> 103 <li>java.security.spec</li> 104 <li>java.sql</li> 105 <li>java.text</li> 106 <li>java.util</li> 107 <li>java.util.concurrent</li> 108 <li>java.util.concurrent.atomic</li> 109 <li>java.util.concurrent.locks</li> 110 <li>java.util.jar</li> 111 <li>java.util.logging</li> 112 <li>java.util.prefs</li> 113 <li>java.util.regex</li> 114 <li>java.util.zip</li> 115 <li>javax.crypto</li> 116 <li>javax.crypto.interfaces</li> 117 <li>javax.crypto.spec</li> 118 <li>javax.net</li> 119 <li>javax.net.ssl</li> 120 <li>javax.security.auth</li> 121 <li>javax.security.auth.callback</li> 122 <li>javax.security.auth.login</li> 123 <li>javax.security.auth.x500</li> 124 <li>javax.security.cert</li> 125 <li>javax.sql</li> 126 <li>javax.xml</li> 127 <li>javax.xml.parsers</li> 128 <li>org.w3c.dom</li> 129 <li>org.xml.sax</li> 130 <li>org.xml.sax.ext</li> 131 <li>org.xml.sax.helpers</li> 132</ul> 133 134<p>We only provide the core functionality of <code>XMLParser</code> and 135<code>DocumentBuilder</code> in the XML packages. Some methods dealing with XML 136schema were left out because we don't provide the corresponding packages.</p> 137 138<p>In addition to the aforementioned packages, we plan to support the following 139packages some time in the future. We currently have an unfinished 140implementation of 2D drawing and image processing.</p> 141 142<ul class="code"> 143 <li>java.awt</li> 144 <li>java.awt.color</li> 145 <li>java.awt.event</li> 146 <li>java.awt.font</li> 147 <li>java.awt.geom</li> 148 <li>java.awt.im</li> 149 <li>java.awt.im.spi</li> 150 <li>java.awt.image</li> 151 <li>java.awt.image.renderable</li> 152 <li>javax.imageio</li> 153 <li>javax.imageio.event</li> 154 <li>javax.imageio.metadata</li> 155 <li>javax.imageio.plugins.bmp</li> 156 <li>javax.imageio.plugins.jpeg</li> 157 <li>javax.imageio.spi</li> 158 <li>javax.imageio.stream</li> 159</ul> 160 161<p style="margin-top: 50px">Copyright © 2008 The Android Open Source 162Project</p> 163 164</body> 165</html> 166
