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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 java.text.MessageFormat;<a name="line.21"></a>
<FONT color="green">022</FONT>    import java.util.List;<a name="line.22"></a>
<FONT color="green">023</FONT>    import java.util.regex.Pattern;<a name="line.23"></a>
<FONT color="green">024</FONT>    <a name="line.24"></a>
<FONT color="green">025</FONT>    /**<a name="line.25"></a>
<FONT color="green">026</FONT>     * Utility methods to check preconditions.<a name="line.26"></a>
<FONT color="green">027</FONT>     * &lt;p/&gt;<a name="line.27"></a>
<FONT color="green">028</FONT>     * Commonly used for method arguments preconditions.<a name="line.28"></a>
<FONT color="green">029</FONT>     */<a name="line.29"></a>
<FONT color="green">030</FONT>    public class Check {<a name="line.30"></a>
<FONT color="green">031</FONT>    <a name="line.31"></a>
<FONT color="green">032</FONT>      /**<a name="line.32"></a>
<FONT color="green">033</FONT>       * Verifies a variable is not NULL.<a name="line.33"></a>
<FONT color="green">034</FONT>       *<a name="line.34"></a>
<FONT color="green">035</FONT>       * @param obj the variable to check.<a name="line.35"></a>
<FONT color="green">036</FONT>       * @param name the name to use in the exception message.<a name="line.36"></a>
<FONT color="green">037</FONT>       *<a name="line.37"></a>
<FONT color="green">038</FONT>       * @return the variable.<a name="line.38"></a>
<FONT color="green">039</FONT>       *<a name="line.39"></a>
<FONT color="green">040</FONT>       * @throws IllegalArgumentException if the variable is NULL.<a name="line.40"></a>
<FONT color="green">041</FONT>       */<a name="line.41"></a>
<FONT color="green">042</FONT>      public static &lt;T&gt; T notNull(T obj, String name) {<a name="line.42"></a>
<FONT color="green">043</FONT>        if (obj == null) {<a name="line.43"></a>
<FONT color="green">044</FONT>          throw new IllegalArgumentException(name + " cannot be null");<a name="line.44"></a>
<FONT color="green">045</FONT>        }<a name="line.45"></a>
<FONT color="green">046</FONT>        return obj;<a name="line.46"></a>
<FONT color="green">047</FONT>      }<a name="line.47"></a>
<FONT color="green">048</FONT>    <a name="line.48"></a>
<FONT color="green">049</FONT>      /**<a name="line.49"></a>
<FONT color="green">050</FONT>       * Verifies a list does not have any NULL elements.<a name="line.50"></a>
<FONT color="green">051</FONT>       *<a name="line.51"></a>
<FONT color="green">052</FONT>       * @param list the list to check.<a name="line.52"></a>
<FONT color="green">053</FONT>       * @param name the name to use in the exception message.<a name="line.53"></a>
<FONT color="green">054</FONT>       *<a name="line.54"></a>
<FONT color="green">055</FONT>       * @return the list.<a name="line.55"></a>
<FONT color="green">056</FONT>       *<a name="line.56"></a>
<FONT color="green">057</FONT>       * @throws IllegalArgumentException if the list has NULL elements.<a name="line.57"></a>
<FONT color="green">058</FONT>       */<a name="line.58"></a>
<FONT color="green">059</FONT>      public static &lt;T&gt; List&lt;T&gt; notNullElements(List&lt;T&gt; list, String name) {<a name="line.59"></a>
<FONT color="green">060</FONT>        notNull(list, name);<a name="line.60"></a>
<FONT color="green">061</FONT>        for (int i = 0; i &lt; list.size(); i++) {<a name="line.61"></a>
<FONT color="green">062</FONT>          notNull(list.get(i), MessageFormat.format("list [{0}] element [{1}]", name, i));<a name="line.62"></a>
<FONT color="green">063</FONT>        }<a name="line.63"></a>
<FONT color="green">064</FONT>        return list;<a name="line.64"></a>
<FONT color="green">065</FONT>      }<a name="line.65"></a>
<FONT color="green">066</FONT>    <a name="line.66"></a>
<FONT color="green">067</FONT>      /**<a name="line.67"></a>
<FONT color="green">068</FONT>       * Verifies a string is not NULL and not emtpy<a name="line.68"></a>
<FONT color="green">069</FONT>       *<a name="line.69"></a>
<FONT color="green">070</FONT>       * @param str the variable to check.<a name="line.70"></a>
<FONT color="green">071</FONT>       * @param name the name to use in the exception message.<a name="line.71"></a>
<FONT color="green">072</FONT>       *<a name="line.72"></a>
<FONT color="green">073</FONT>       * @return the variable.<a name="line.73"></a>
<FONT color="green">074</FONT>       *<a name="line.74"></a>
<FONT color="green">075</FONT>       * @throws IllegalArgumentException if the variable is NULL or empty.<a name="line.75"></a>
<FONT color="green">076</FONT>       */<a name="line.76"></a>
<FONT color="green">077</FONT>      public static String notEmpty(String str, String name) {<a name="line.77"></a>
<FONT color="green">078</FONT>        if (str == null) {<a name="line.78"></a>
<FONT color="green">079</FONT>          throw new IllegalArgumentException(name + " cannot be null");<a name="line.79"></a>
<FONT color="green">080</FONT>        }<a name="line.80"></a>
<FONT color="green">081</FONT>        if (str.length() == 0) {<a name="line.81"></a>
<FONT color="green">082</FONT>          throw new IllegalArgumentException(name + " cannot be empty");<a name="line.82"></a>
<FONT color="green">083</FONT>        }<a name="line.83"></a>
<FONT color="green">084</FONT>        return str;<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>      /**<a name="line.87"></a>
<FONT color="green">088</FONT>       * Verifies a string list is not NULL and not emtpy<a name="line.88"></a>
<FONT color="green">089</FONT>       *<a name="line.89"></a>
<FONT color="green">090</FONT>       * @param list the list to check.<a name="line.90"></a>
<FONT color="green">091</FONT>       * @param name the name to use in the exception message.<a name="line.91"></a>
<FONT color="green">092</FONT>       *<a name="line.92"></a>
<FONT color="green">093</FONT>       * @return the variable.<a name="line.93"></a>
<FONT color="green">094</FONT>       *<a name="line.94"></a>
<FONT color="green">095</FONT>       * @throws IllegalArgumentException if the string list has NULL or empty<a name="line.95"></a>
<FONT color="green">096</FONT>       * elements.<a name="line.96"></a>
<FONT color="green">097</FONT>       */<a name="line.97"></a>
<FONT color="green">098</FONT>      public static List&lt;String&gt; notEmptyElements(List&lt;String&gt; list, String name) {<a name="line.98"></a>
<FONT color="green">099</FONT>        notNull(list, name);<a name="line.99"></a>
<FONT color="green">100</FONT>        for (int i = 0; i &lt; list.size(); i++) {<a name="line.100"></a>
<FONT color="green">101</FONT>          notEmpty(list.get(i), MessageFormat.format("list [{0}] element [{1}]", name, i));<a name="line.101"></a>
<FONT color="green">102</FONT>        }<a name="line.102"></a>
<FONT color="green">103</FONT>        return list;<a name="line.103"></a>
<FONT color="green">104</FONT>      }<a name="line.104"></a>
<FONT color="green">105</FONT>    <a name="line.105"></a>
<FONT color="green">106</FONT>      private static final String IDENTIFIER_PATTERN_STR = "[a-zA-z_][a-zA-Z0-9_\\-]*";<a name="line.106"></a>
<FONT color="green">107</FONT>    <a name="line.107"></a>
<FONT color="green">108</FONT>      private static final Pattern IDENTIFIER_PATTERN = Pattern.compile("^" + IDENTIFIER_PATTERN_STR + "$");<a name="line.108"></a>
<FONT color="green">109</FONT>    <a name="line.109"></a>
<FONT color="green">110</FONT>      /**<a name="line.110"></a>
<FONT color="green">111</FONT>       * Verifies a value is a valid identifier,<a name="line.111"></a>
<FONT color="green">112</FONT>       * &lt;code&gt;[a-zA-z_][a-zA-Z0-9_\-]*&lt;/code&gt;, up to a maximum length.<a name="line.112"></a>
<FONT color="green">113</FONT>       *<a name="line.113"></a>
<FONT color="green">114</FONT>       * @param value string to check if it is a valid identifier.<a name="line.114"></a>
<FONT color="green">115</FONT>       * @param maxLen maximun length.<a name="line.115"></a>
<FONT color="green">116</FONT>       * @param name the name to use in the exception message.<a name="line.116"></a>
<FONT color="green">117</FONT>       *<a name="line.117"></a>
<FONT color="green">118</FONT>       * @return the value.<a name="line.118"></a>
<FONT color="green">119</FONT>       *<a name="line.119"></a>
<FONT color="green">120</FONT>       * @throws IllegalArgumentException if the string is not a valid identifier.<a name="line.120"></a>
<FONT color="green">121</FONT>       */<a name="line.121"></a>
<FONT color="green">122</FONT>      public static String validIdentifier(String value, int maxLen, String name) {<a name="line.122"></a>
<FONT color="green">123</FONT>        Check.notEmpty(value, name);<a name="line.123"></a>
<FONT color="green">124</FONT>        if (value.length() &gt; maxLen) {<a name="line.124"></a>
<FONT color="green">125</FONT>          throw new IllegalArgumentException(<a name="line.125"></a>
<FONT color="green">126</FONT>            MessageFormat.format("[{0}] = [{1}] exceeds max len [{2}]", name, value, maxLen));<a name="line.126"></a>
<FONT color="green">127</FONT>        }<a name="line.127"></a>
<FONT color="green">128</FONT>        if (!IDENTIFIER_PATTERN.matcher(value).find()) {<a name="line.128"></a>
<FONT color="green">129</FONT>          throw new IllegalArgumentException(<a name="line.129"></a>
<FONT color="green">130</FONT>            MessageFormat.format("[{0}] = [{1}] must be '{2}'", name, value, IDENTIFIER_PATTERN_STR));<a name="line.130"></a>
<FONT color="green">131</FONT>        }<a name="line.131"></a>
<FONT color="green">132</FONT>        return value;<a name="line.132"></a>
<FONT color="green">133</FONT>      }<a name="line.133"></a>
<FONT color="green">134</FONT>    <a name="line.134"></a>
<FONT color="green">135</FONT>      /**<a name="line.135"></a>
<FONT color="green">136</FONT>       * Verifies an integer is greater than zero.<a name="line.136"></a>
<FONT color="green">137</FONT>       *<a name="line.137"></a>
<FONT color="green">138</FONT>       * @param value integer value.<a name="line.138"></a>
<FONT color="green">139</FONT>       * @param name the name to use in the exception message.<a name="line.139"></a>
<FONT color="green">140</FONT>       *<a name="line.140"></a>
<FONT color="green">141</FONT>       * @return the value.<a name="line.141"></a>
<FONT color="green">142</FONT>       *<a name="line.142"></a>
<FONT color="green">143</FONT>       * @throws IllegalArgumentException if the integer is zero or less.<a name="line.143"></a>
<FONT color="green">144</FONT>       */<a name="line.144"></a>
<FONT color="green">145</FONT>      public static int gt0(int value, String name) {<a name="line.145"></a>
<FONT color="green">146</FONT>        return (int) gt0((long) value, name);<a name="line.146"></a>
<FONT color="green">147</FONT>      }<a name="line.147"></a>
<FONT color="green">148</FONT>    <a name="line.148"></a>
<FONT color="green">149</FONT>      /**<a name="line.149"></a>
<FONT color="green">150</FONT>       * Verifies an long is greater than zero.<a name="line.150"></a>
<FONT color="green">151</FONT>       *<a name="line.151"></a>
<FONT color="green">152</FONT>       * @param value long value.<a name="line.152"></a>
<FONT color="green">153</FONT>       * @param name the name to use in the exception message.<a name="line.153"></a>
<FONT color="green">154</FONT>       *<a name="line.154"></a>
<FONT color="green">155</FONT>       * @return the value.<a name="line.155"></a>
<FONT color="green">156</FONT>       *<a name="line.156"></a>
<FONT color="green">157</FONT>       * @throws IllegalArgumentException if the long is zero or less.<a name="line.157"></a>
<FONT color="green">158</FONT>       */<a name="line.158"></a>
<FONT color="green">159</FONT>      public static long gt0(long value, String name) {<a name="line.159"></a>
<FONT color="green">160</FONT>        if (value &lt;= 0) {<a name="line.160"></a>
<FONT color="green">161</FONT>          throw new IllegalArgumentException(<a name="line.161"></a>
<FONT color="green">162</FONT>            MessageFormat.format("parameter [{0}] = [{1}] must be greater than zero", name, value));<a name="line.162"></a>
<FONT color="green">163</FONT>        }<a name="line.163"></a>
<FONT color="green">164</FONT>        return value;<a name="line.164"></a>
<FONT color="green">165</FONT>      }<a name="line.165"></a>
<FONT color="green">166</FONT>    <a name="line.166"></a>
<FONT color="green">167</FONT>      /**<a name="line.167"></a>
<FONT color="green">168</FONT>       * Verifies an integer is greater or equal to zero.<a name="line.168"></a>
<FONT color="green">169</FONT>       *<a name="line.169"></a>
<FONT color="green">170</FONT>       * @param value integer value.<a name="line.170"></a>
<FONT color="green">171</FONT>       * @param name the name to use in the exception message.<a name="line.171"></a>
<FONT color="green">172</FONT>       *<a name="line.172"></a>
<FONT color="green">173</FONT>       * @return the value.<a name="line.173"></a>
<FONT color="green">174</FONT>       *<a name="line.174"></a>
<FONT color="green">175</FONT>       * @throws IllegalArgumentException if the integer is greater or equal to zero.<a name="line.175"></a>
<FONT color="green">176</FONT>       */<a name="line.176"></a>
<FONT color="green">177</FONT>      public static int ge0(int value, String name) {<a name="line.177"></a>
<FONT color="green">178</FONT>        return (int) ge0((long) value, name);<a name="line.178"></a>
<FONT color="green">179</FONT>      }<a name="line.179"></a>
<FONT color="green">180</FONT>    <a name="line.180"></a>
<FONT color="green">181</FONT>      /**<a name="line.181"></a>
<FONT color="green">182</FONT>       * Verifies an long is greater or equal to zero.<a name="line.182"></a>
<FONT color="green">183</FONT>       *<a name="line.183"></a>
<FONT color="green">184</FONT>       * @param value integer value.<a name="line.184"></a>
<FONT color="green">185</FONT>       * @param name the name to use in the exception message.<a name="line.185"></a>
<FONT color="green">186</FONT>       *<a name="line.186"></a>
<FONT color="green">187</FONT>       * @return the value.<a name="line.187"></a>
<FONT color="green">188</FONT>       *<a name="line.188"></a>
<FONT color="green">189</FONT>       * @throws IllegalArgumentException if the long is greater or equal to zero.<a name="line.189"></a>
<FONT color="green">190</FONT>       */<a name="line.190"></a>
<FONT color="green">191</FONT>      public static long ge0(long value, String name) {<a name="line.191"></a>
<FONT color="green">192</FONT>        if (value &lt; 0) {<a name="line.192"></a>
<FONT color="green">193</FONT>          throw new IllegalArgumentException(MessageFormat.format(<a name="line.193"></a>
<FONT color="green">194</FONT>            "parameter [{0}] = [{1}] must be greater than or equals zero", name, value));<a name="line.194"></a>
<FONT color="green">195</FONT>        }<a name="line.195"></a>
<FONT color="green">196</FONT>        return value;<a name="line.196"></a>
<FONT color="green">197</FONT>      }<a name="line.197"></a>
<FONT color="green">198</FONT>    <a name="line.198"></a>
<FONT color="green">199</FONT>    }<a name="line.199"></a>




























































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