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<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"><html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en"><head><meta http-equiv="content-type" content="text/html; charset=ISO-8859-1" /><title>Base64 xref</title><link type="text/css" rel="stylesheet" href="../../../../../stylesheet.css" /></head><body><div id="overview"><a href="../../../../../../apidocs/com/sun/syndication/io/impl/Base64.html">View Javadoc</a></div><pre><a name="1" href="#1">1</a> <strong>package</strong> <a href="../../../../../com/sun/syndication/io/impl/package-summary.html">com.sun.syndication.io.impl</a>;<a name="2" href="#2">2</a> <a name="3" href="#3">3</a> <em class="comment">/*</em><a name="4" href="#4">4</a> <em class="comment"> * Copyright 2004 Sun Microsystems, Inc.</em><a name="5" href="#5">5</a> <em class="comment"> *</em><a name="6" href="#6">6</a> <em class="comment"> * Licensed under the Apache License, Version 2.0 (the "License");</em><a name="7" href="#7">7</a> <em class="comment"> * you may not use this file except in compliance with the License.</em><a name="8" href="#8">8</a> <em class="comment"> * You may obtain a copy of the License at</em><a name="9" href="#9">9</a> <em class="comment"> *</em><a name="10" href="#10">10</a> <em class="comment"> * <a href="http://www.apache.org/licenses/LICENSE-2.0" target="alexandria_uri">http://www.apache.org/licenses/LICENSE-2.0</a></em><a name="11" href="#11">11</a> <em class="comment"> *</em><a name="12" href="#12">12</a> <em class="comment"> * Unless required by applicable law or agreed to in writing, software</em><a name="13" href="#13">13</a> <em class="comment"> * distributed under the License is distributed on an "AS IS" BASIS,</em><a name="14" href="#14">14</a> <em class="comment"> * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.</em><a name="15" href="#15">15</a> <em class="comment"> * See the License for the specific language governing permissions and</em><a name="16" href="#16">16</a> <em class="comment"> * limitations under the License.</em><a name="17" href="#17">17</a> <em class="comment"> *</em><a name="18" href="#18">18</a> <em class="comment"> */</em><a name="19" href="#19">19</a> <a name="20" href="#20">20</a> <em>/**<em>*</em></em><a name="21" href="#21">21</a> <em> * Encodes/decodes byte arrays and Strings into/from a base 64 String.</em><a name="22" href="#22">22</a> <em> * <p></em><a name="23" href="#23">23</a> <em> * @author Alejandro Abdelnur</em><a name="24" href="#24">24</a> <em> *</em><a name="25" href="#25">25</a> <em> */</em><a name="26" href="#26">26</a> <strong>public</strong> <strong>class</strong> Base64 {<a name="27" href="#27">27</a> <a name="28" href="#28">28</a> <em>/**<em>*</em></em><a name="29" href="#29">29</a> <em> * Encodes a String into a base 64 String. The resulting encoding is chunked at 76 bytes.</em><a name="30" href="#30">30</a> <em> * <p></em><a name="31" href="#31">31</a> <em> * @param s String to encode.</em><a name="32" href="#32">32</a> <em> * @return encoded string.</em><a name="33" href="#33">33</a> <em> *</em><a name="34" href="#34">34</a> <em> */</em><a name="35" href="#35">35</a> <strong>public</strong> <strong>static</strong> String encode(String s) {<a name="36" href="#36">36</a> byte[] sBytes = s.getBytes();<a name="37" href="#37">37</a> sBytes = encode(sBytes);<a name="38" href="#38">38</a> s = <strong>new</strong> String(sBytes);<a name="39" href="#39">39</a> <strong>return</strong> s;<a name="40" href="#40">40</a> }<a name="41" href="#41">41</a> <a name="42" href="#42">42</a> <em>/**<em>*</em></em><a name="43" href="#43">43</a> <em> * Decodes a base 64 String into a String.</em><a name="44" href="#44">44</a> <em> * <p></em><a name="45" href="#45">45</a> <em> * @param s String to decode.</em><a name="46" href="#46">46</a> <em> * @return encoded string.</em><a name="47" href="#47">47</a> <em> * @throws java.lang.IllegalArgumentException thrown if the given byte array was not valid com.sun.syndication.io.impl.Base64 encoding.</em><a name="48" href="#48">48</a> <em> *</em><a name="49" href="#49">49</a> <em> */</em><a name="50" href="#50">50</a> <strong>public</strong> <strong>static</strong> String decode(String s) throws IllegalArgumentException {<a name="51" href="#51">51</a> byte[] sBytes = s.getBytes();<a name="52" href="#52">52</a> sBytes = decode(sBytes);<a name="53" href="#53">53</a> s = <strong>new</strong> String(sBytes);<a name="54" href="#54">54</a> <strong>return</strong> s;<a name="55" href="#55">55</a> }<a name="56" href="#56">56</a> <a name="57" href="#57">57</a> <a name="58" href="#58">58</a> <strong>private</strong> <strong>static</strong> <strong>final</strong> byte[] ALPHASET =<a name="59" href="#59">59</a> <span class="string">"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/="</span>.getBytes();<a name="60" href="#60">60</a> <a name="61" href="#61">61</a> <strong>private</strong> <strong>static</strong> <strong>final</strong> <strong>int</strong> I6O2 = 255 - 3;<a name="62" href="#62">62</a> <strong>private</strong> <strong>static</strong> <strong>final</strong> <strong>int</strong> O6I2 = 3;<a name="63" href="#63">63</a> <strong>private</strong> <strong>static</strong> <strong>final</strong> <strong>int</strong> I4O4 = 255 - 15;<a name="64" href="#64">64</a> <strong>private</strong> <strong>static</strong> <strong>final</strong> <strong>int</strong> O4I4 = 15;<a name="65" href="#65">65</a> <strong>private</strong> <strong>static</strong> <strong>final</strong> <strong>int</strong> I2O6 = 255 - 63;<a name="66" href="#66">66</a> <strong>private</strong> <strong>static</strong> <strong>final</strong> <strong>int</strong> O2I6 = 63;<a name="67" href="#67">67</a> <a name="68" href="#68">68</a> <em>/**<em>*</em></em><a name="69" href="#69">69</a> <em> * Encodes a byte array into a base 64 byte array.</em><a name="70" href="#70">70</a> <em> * <p></em><a name="71" href="#71">71</a> <em> * @param dData byte array to encode.</em><a name="72" href="#72">72</a> <em> * @return encoded byte array.</em><a name="73" href="#73">73</a> <em> *</em><a name="74" href="#74">74</a> <em> */</em><a name="75" href="#75">75</a> <strong>public</strong> <strong>static</strong> byte[] encode(byte[] dData) {<a name="76" href="#76">76</a> <strong>if</strong> (dData==<strong>null</strong>) {<a name="77" href="#77">77</a> <strong>throw</strong> <strong>new</strong> IllegalArgumentException(<span class="string">"Cannot encode null"</span>);<a name="78" href="#78">78</a> }<a name="79" href="#79">79</a> byte[] eData = <strong>new</strong> byte[((dData.length+2)/3)*4];<a name="80" href="#80">80</a> <a name="81" href="#81">81</a> <strong>int</strong> eIndex = 0;<a name="82" href="#82">82</a> <strong>for</strong> (<strong>int</strong> i = 0; i<dData.length; i += 3) {<a name="83" href="#83">83</a> <strong>int</strong> d1;<a name="84" href="#84">84</a> <strong>int</strong> d2=0;<a name="85" href="#85">85</a> <strong>int</strong> d3=0;<a name="86" href="#86">86</a> <strong>int</strong> e1;<a name="87" href="#87">87</a> <strong>int</strong> e2;<a name="88" href="#88">88</a> <strong>int</strong> e3;<a name="89" href="#89">89</a> <strong>int</strong> e4;<a name="90" href="#90">90</a> <strong>int</strong> pad=0;<a name="91" href="#91">91</a> <a name="92" href="#92">92</a> d1 = dData[i];<a name="93" href="#93">93</a> <strong>if</strong> ((i+1)<dData.length) {<a name="94" href="#94">94</a> d2 = dData[i+1];<a name="95" href="#95">95</a> <strong>if</strong> ((i+2)<dData.length) {<a name="96" href="#96">96</a> d3 = dData[i+2];<a name="97" href="#97">97</a> }<a name="98" href="#98">98</a> <strong>else</strong> {⌨️ 快捷键说明
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