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<FONT color="green">001</FONT>    /**<a name="line.1"></a>
<FONT color="green">002</FONT>     * Licensed to the Apache Software Foundation (ASF) under one<a name="line.2"></a>
<FONT color="green">003</FONT>     * or more contributor license agreements.  See the NOTICE file<a name="line.3"></a>
<FONT color="green">004</FONT>     * distributed with this work for additional information<a name="line.4"></a>
<FONT color="green">005</FONT>     * regarding copyright ownership.  The ASF licenses this file<a name="line.5"></a>
<FONT color="green">006</FONT>     * to you under the Apache License, Version 2.0 (the<a name="line.6"></a>
<FONT color="green">007</FONT>     * "License"); you may not use this file except in compliance<a name="line.7"></a>
<FONT color="green">008</FONT>     * with the License.  You may obtain a copy of the License at<a name="line.8"></a>
<FONT color="green">009</FONT>     *<a name="line.9"></a>
<FONT color="green">010</FONT>     *     http://www.apache.org/licenses/LICENSE-2.0<a name="line.10"></a>
<FONT color="green">011</FONT>     *<a name="line.11"></a>
<FONT color="green">012</FONT>     * Unless required by applicable law or agreed to in writing, software<a name="line.12"></a>
<FONT color="green">013</FONT>     * distributed under the License is distributed on an "AS IS" BASIS,<a name="line.13"></a>
<FONT color="green">014</FONT>     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.<a name="line.14"></a>
<FONT color="green">015</FONT>     * See the License for the specific language governing permissions and<a name="line.15"></a>
<FONT color="green">016</FONT>     * limitations under the License.<a name="line.16"></a>
<FONT color="green">017</FONT>     */<a name="line.17"></a>
<FONT color="green">018</FONT>    <a name="line.18"></a>
<FONT color="green">019</FONT>    package org.apache.hadoop.lib.util;<a name="line.19"></a>
<FONT color="green">020</FONT>    <a name="line.20"></a>
<FONT color="green">021</FONT>    import org.apache.hadoop.conf.Configuration;<a name="line.21"></a>
<FONT color="green">022</FONT>    import org.w3c.dom.DOMException;<a name="line.22"></a>
<FONT color="green">023</FONT>    import org.w3c.dom.Document;<a name="line.23"></a>
<FONT color="green">024</FONT>    import org.w3c.dom.Element;<a name="line.24"></a>
<FONT color="green">025</FONT>    import org.w3c.dom.Node;<a name="line.25"></a>
<FONT color="green">026</FONT>    import org.w3c.dom.NodeList;<a name="line.26"></a>
<FONT color="green">027</FONT>    import org.w3c.dom.Text;<a name="line.27"></a>
<FONT color="green">028</FONT>    import org.xml.sax.SAXException;<a name="line.28"></a>
<FONT color="green">029</FONT>    <a name="line.29"></a>
<FONT color="green">030</FONT>    import javax.xml.parsers.DocumentBuilder;<a name="line.30"></a>
<FONT color="green">031</FONT>    import javax.xml.parsers.DocumentBuilderFactory;<a name="line.31"></a>
<FONT color="green">032</FONT>    import javax.xml.parsers.ParserConfigurationException;<a name="line.32"></a>
<FONT color="green">033</FONT>    import java.io.IOException;<a name="line.33"></a>
<FONT color="green">034</FONT>    import java.io.InputStream;<a name="line.34"></a>
<FONT color="green">035</FONT>    import java.util.Map;<a name="line.35"></a>
<FONT color="green">036</FONT>    <a name="line.36"></a>
<FONT color="green">037</FONT>    /**<a name="line.37"></a>
<FONT color="green">038</FONT>     * Configuration utilities.<a name="line.38"></a>
<FONT color="green">039</FONT>     */<a name="line.39"></a>
<FONT color="green">040</FONT>    public abstract class ConfigurationUtils {<a name="line.40"></a>
<FONT color="green">041</FONT>    <a name="line.41"></a>
<FONT color="green">042</FONT>      /**<a name="line.42"></a>
<FONT color="green">043</FONT>       * Copy configuration key/value pairs from one configuration to another if a property exists in the target, it gets<a name="line.43"></a>
<FONT color="green">044</FONT>       * replaced.<a name="line.44"></a>
<FONT color="green">045</FONT>       *<a name="line.45"></a>
<FONT color="green">046</FONT>       * @param source source configuration.<a name="line.46"></a>
<FONT color="green">047</FONT>       * @param target target configuration.<a name="line.47"></a>
<FONT color="green">048</FONT>       */<a name="line.48"></a>
<FONT color="green">049</FONT>      public static void copy(Configuration source, Configuration target) {<a name="line.49"></a>
<FONT color="green">050</FONT>        Check.notNull(source, "source");<a name="line.50"></a>
<FONT color="green">051</FONT>        Check.notNull(target, "target");<a name="line.51"></a>
<FONT color="green">052</FONT>        for (Map.Entry&lt;String, String&gt; entry : source) {<a name="line.52"></a>
<FONT color="green">053</FONT>          target.set(entry.getKey(), entry.getValue());<a name="line.53"></a>
<FONT color="green">054</FONT>        }<a name="line.54"></a>
<FONT color="green">055</FONT>      }<a name="line.55"></a>
<FONT color="green">056</FONT>    <a name="line.56"></a>
<FONT color="green">057</FONT>      /**<a name="line.57"></a>
<FONT color="green">058</FONT>       * Injects configuration key/value pairs from one configuration to another if the key does not exist in the target<a name="line.58"></a>
<FONT color="green">059</FONT>       * configuration.<a name="line.59"></a>
<FONT color="green">060</FONT>       *<a name="line.60"></a>
<FONT color="green">061</FONT>       * @param source source configuration.<a name="line.61"></a>
<FONT color="green">062</FONT>       * @param target target configuration.<a name="line.62"></a>
<FONT color="green">063</FONT>       */<a name="line.63"></a>
<FONT color="green">064</FONT>      public static void injectDefaults(Configuration source, Configuration target) {<a name="line.64"></a>
<FONT color="green">065</FONT>        Check.notNull(source, "source");<a name="line.65"></a>
<FONT color="green">066</FONT>        Check.notNull(target, "target");<a name="line.66"></a>
<FONT color="green">067</FONT>        for (Map.Entry&lt;String, String&gt; entry : source) {<a name="line.67"></a>
<FONT color="green">068</FONT>          if (target.get(entry.getKey()) == null) {<a name="line.68"></a>
<FONT color="green">069</FONT>            target.set(entry.getKey(), entry.getValue());<a name="line.69"></a>
<FONT color="green">070</FONT>          }<a name="line.70"></a>
<FONT color="green">071</FONT>        }<a name="line.71"></a>
<FONT color="green">072</FONT>      }<a name="line.72"></a>
<FONT color="green">073</FONT>    <a name="line.73"></a>
<FONT color="green">074</FONT>      /**<a name="line.74"></a>
<FONT color="green">075</FONT>       * Returns a new ConfigurationUtils instance with all inline values resolved.<a name="line.75"></a>
<FONT color="green">076</FONT>       *<a name="line.76"></a>
<FONT color="green">077</FONT>       * @return a new ConfigurationUtils instance with all inline values resolved.<a name="line.77"></a>
<FONT color="green">078</FONT>       */<a name="line.78"></a>
<FONT color="green">079</FONT>      public static Configuration resolve(Configuration conf) {<a name="line.79"></a>
<FONT color="green">080</FONT>        Configuration resolved = new Configuration(false);<a name="line.80"></a>
<FONT color="green">081</FONT>        for (Map.Entry&lt;String, String&gt; entry : conf) {<a name="line.81"></a>
<FONT color="green">082</FONT>          resolved.set(entry.getKey(), conf.get(entry.getKey()));<a name="line.82"></a>
<FONT color="green">083</FONT>        }<a name="line.83"></a>
<FONT color="green">084</FONT>        return resolved;<a name="line.84"></a>
<FONT color="green">085</FONT>      }<a name="line.85"></a>
<FONT color="green">086</FONT>    <a name="line.86"></a>
<FONT color="green">087</FONT>      // Canibalized from FileSystemAccess &lt;code&gt;Configuration.loadResource()&lt;/code&gt;.<a name="line.87"></a>
<FONT color="green">088</FONT>    <a name="line.88"></a>
<FONT color="green">089</FONT>      /**<a name="line.89"></a>
<FONT color="green">090</FONT>       * Create a configuration from an InputStream.<a name="line.90"></a>
<FONT color="green">091</FONT>       * &lt;p/&gt;<a name="line.91"></a>
<FONT color="green">092</FONT>       * ERROR canibalized from &lt;code&gt;Configuration.loadResource()&lt;/code&gt;.<a name="line.92"></a>
<FONT color="green">093</FONT>       *<a name="line.93"></a>
<FONT color="green">094</FONT>       * @param is inputstream to read the configuration from.<a name="line.94"></a>
<FONT color="green">095</FONT>       *<a name="line.95"></a>
<FONT color="green">096</FONT>       * @throws IOException thrown if the configuration could not be read.<a name="line.96"></a>
<FONT color="green">097</FONT>       */<a name="line.97"></a>
<FONT color="green">098</FONT>      public static void load(Configuration conf, InputStream is) throws IOException {<a name="line.98"></a>
<FONT color="green">099</FONT>        try {<a name="line.99"></a>
<FONT color="green">100</FONT>          DocumentBuilderFactory docBuilderFactory = DocumentBuilderFactory.newInstance();<a name="line.100"></a>
<FONT color="green">101</FONT>          // ignore all comments inside the xml file<a name="line.101"></a>
<FONT color="green">102</FONT>          docBuilderFactory.setIgnoringComments(true);<a name="line.102"></a>
<FONT color="green">103</FONT>          DocumentBuilder builder = docBuilderFactory.newDocumentBuilder();<a name="line.103"></a>
<FONT color="green">104</FONT>          Document doc = builder.parse(is);<a name="line.104"></a>
<FONT color="green">105</FONT>          parseDocument(conf, doc);<a name="line.105"></a>
<FONT color="green">106</FONT>        } catch (SAXException e) {<a name="line.106"></a>
<FONT color="green">107</FONT>          throw new IOException(e);<a name="line.107"></a>
<FONT color="green">108</FONT>        } catch (ParserConfigurationException e) {<a name="line.108"></a>
<FONT color="green">109</FONT>          throw new IOException(e);<a name="line.109"></a>
<FONT color="green">110</FONT>        }<a name="line.110"></a>
<FONT color="green">111</FONT>      }<a name="line.111"></a>
<FONT color="green">112</FONT>    <a name="line.112"></a>
<FONT color="green">113</FONT>      // Canibalized from FileSystemAccess &lt;code&gt;Configuration.loadResource()&lt;/code&gt;.<a name="line.113"></a>
<FONT color="green">114</FONT>      private static void parseDocument(Configuration conf, Document doc) throws IOException {<a name="line.114"></a>
<FONT color="green">115</FONT>        try {<a name="line.115"></a>
<FONT color="green">116</FONT>          Element root = doc.getDocumentElement();<a name="line.116"></a>
<FONT color="green">117</FONT>          if (!"configuration".equals(root.getTagName())) {<a name="line.117"></a>
<FONT color="green">118</FONT>            throw new IOException("bad conf file: top-level element not &lt;configuration&gt;");<a name="line.118"></a>
<FONT color="green">119</FONT>          }<a name="line.119"></a>
<FONT color="green">120</FONT>          NodeList props = root.getChildNodes();<a name="line.120"></a>
<FONT color="green">121</FONT>          for (int i = 0; i &lt; props.getLength(); i++) {<a name="line.121"></a>
<FONT color="green">122</FONT>            Node propNode = props.item(i);<a name="line.122"></a>
<FONT color="green">123</FONT>            if (!(propNode instanceof Element)) {<a name="line.123"></a>
<FONT color="green">124</FONT>              continue;<a name="line.124"></a>
<FONT color="green">125</FONT>            }<a name="line.125"></a>
<FONT color="green">126</FONT>            Element prop = (Element) propNode;<a name="line.126"></a>
<FONT color="green">127</FONT>            if (!"property".equals(prop.getTagName())) {<a name="line.127"></a>
<FONT color="green">128</FONT>              throw new IOException("bad conf file: element not &lt;property&gt;");<a name="line.128"></a>
<FONT color="green">129</FONT>            }<a name="line.129"></a>
<FONT color="green">130</FONT>            NodeList fields = prop.getChildNodes();<a name="line.130"></a>
<FONT color="green">131</FONT>            String attr = null;<a name="line.131"></a>
<FONT color="green">132</FONT>            String value = null;<a name="line.132"></a>
<FONT color="green">133</FONT>            for (int j = 0; j &lt; fields.getLength(); j++) {<a name="line.133"></a>
<FONT color="green">134</FONT>              Node fieldNode = fields.item(j);<a name="line.134"></a>
<FONT color="green">135</FONT>              if (!(fieldNode instanceof Element)) {<a name="line.135"></a>
<FONT color="green">136</FONT>                continue;<a name="line.136"></a>
<FONT color="green">137</FONT>              }<a name="line.137"></a>
<FONT color="green">138</FONT>              Element field = (Element) fieldNode;<a name="line.138"></a>
<FONT color="green">139</FONT>              if ("name".equals(field.getTagName()) &amp;&amp; field.hasChildNodes()) {<a name="line.139"></a>
<FONT color="green">140</FONT>                attr = ((Text) field.getFirstChild()).getData().trim();<a name="line.140"></a>
<FONT color="green">141</FONT>              }<a name="line.141"></a>
<FONT color="green">142</FONT>              if ("value".equals(field.getTagName()) &amp;&amp; field.hasChildNodes()) {<a name="line.142"></a>
<FONT color="green">143</FONT>                value = ((Text) field.getFirstChild()).getData();<a name="line.143"></a>
<FONT color="green">144</FONT>              }<a name="line.144"></a>
<FONT color="green">145</FONT>            }<a name="line.145"></a>
<FONT color="green">146</FONT>    <a name="line.146"></a>
<FONT color="green">147</FONT>            if (attr != null &amp;&amp; value != null) {<a name="line.147"></a>
<FONT color="green">148</FONT>              conf.set(attr, value);<a name="line.148"></a>
<FONT color="green">149</FONT>            }<a name="line.149"></a>
<FONT color="green">150</FONT>          }<a name="line.150"></a>
<FONT color="green">151</FONT>    <a name="line.151"></a>
<FONT color="green">152</FONT>        } catch (DOMException e) {<a name="line.152"></a>
<FONT color="green">153</FONT>          throw new IOException(e);<a name="line.153"></a>
<FONT color="green">154</FONT>        }<a name="line.154"></a>
<FONT color="green">155</FONT>      }<a name="line.155"></a>
<FONT color="green">156</FONT>    <a name="line.156"></a>
<FONT color="green">157</FONT>    }<a name="line.157"></a>




























































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