<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html lang="en">
<head>
<title>Source code</title>
<link rel="stylesheet" type="text/css" href="../../../../../stylesheet_fedx.css" title="Style">
</head>
<body>
<div class="sourceContainer">
<pre><span class="sourceLineNo">001</span>/*<a name="line.1"></a>
<span class="sourceLineNo">002</span> * Copyright (C) 2008-2013, fluid Operations AG<a name="line.2"></a>
<span class="sourceLineNo">003</span> *<a name="line.3"></a>
<span class="sourceLineNo">004</span> * FedX is free software: you can redistribute it and/or modify<a name="line.4"></a>
<span class="sourceLineNo">005</span> * it under the terms of the GNU Affero General Public License as<a name="line.5"></a>
<span class="sourceLineNo">006</span> * published by the Free Software Foundation, either version 3 of the<a name="line.6"></a>
<span class="sourceLineNo">007</span> * License, or (at your option) any later version.<a name="line.7"></a>
<span class="sourceLineNo">008</span> * <a name="line.8"></a>
<span class="sourceLineNo">009</span> * This program is distributed in the hope that it will be useful,<a name="line.9"></a>
<span class="sourceLineNo">010</span> * but WITHOUT ANY WARRANTY; without even the implied warranty of<a name="line.10"></a>
<span class="sourceLineNo">011</span> * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the<a name="line.11"></a>
<span class="sourceLineNo">012</span> * GNU Affero General Public License for more details.<a name="line.12"></a>
<span class="sourceLineNo">013</span> * <a name="line.13"></a>
<span class="sourceLineNo">014</span> * You should have received a copy of the GNU Affero General Public License<a name="line.14"></a>
<span class="sourceLineNo">015</span> * along with this program.  If not, see &lt;http://www.gnu.org/licenses/&gt;.<a name="line.15"></a>
<span class="sourceLineNo">016</span> */<a name="line.16"></a>
<span class="sourceLineNo">017</span><a name="line.17"></a>
<span class="sourceLineNo">018</span>package com.fluidops.fedx.exception;<a name="line.18"></a>
<span class="sourceLineNo">019</span><a name="line.19"></a>
<span class="sourceLineNo">020</span>import java.lang.reflect.Constructor;<a name="line.20"></a>
<span class="sourceLineNo">021</span>import java.net.SocketException;<a name="line.21"></a>
<span class="sourceLineNo">022</span>import java.util.regex.Matcher;<a name="line.22"></a>
<span class="sourceLineNo">023</span>import java.util.regex.Pattern;<a name="line.23"></a>
<span class="sourceLineNo">024</span><a name="line.24"></a>
<span class="sourceLineNo">025</span>import org.apache.log4j.Logger;<a name="line.25"></a>
<span class="sourceLineNo">026</span>import org.openrdf.query.QueryEvaluationException;<a name="line.26"></a>
<span class="sourceLineNo">027</span>import org.openrdf.repository.RepositoryConnection;<a name="line.27"></a>
<span class="sourceLineNo">028</span>import org.openrdf.repository.RepositoryException;<a name="line.28"></a>
<span class="sourceLineNo">029</span><a name="line.29"></a>
<span class="sourceLineNo">030</span>import com.fluidops.fedx.EndpointManager;<a name="line.30"></a>
<span class="sourceLineNo">031</span>import com.fluidops.fedx.structures.Endpoint;<a name="line.31"></a>
<span class="sourceLineNo">032</span><a name="line.32"></a>
<span class="sourceLineNo">033</span>/**<a name="line.33"></a>
<span class="sourceLineNo">034</span> * Convenience functions to handle exceptions.<a name="line.34"></a>
<span class="sourceLineNo">035</span> * <a name="line.35"></a>
<span class="sourceLineNo">036</span> * @author Andreas Schwarte<a name="line.36"></a>
<span class="sourceLineNo">037</span> *<a name="line.37"></a>
<span class="sourceLineNo">038</span> */<a name="line.38"></a>
<span class="sourceLineNo">039</span>public class ExceptionUtil {<a name="line.39"></a>
<span class="sourceLineNo">040</span><a name="line.40"></a>
<span class="sourceLineNo">041</span>        protected static Logger log = Logger.getLogger(ExceptionUtil.class);<a name="line.41"></a>
<span class="sourceLineNo">042</span>        <a name="line.42"></a>
<span class="sourceLineNo">043</span>        /**<a name="line.43"></a>
<span class="sourceLineNo">044</span>         * Regex pattern to identify http error codes from the title of the returned document:<a name="line.44"></a>
<span class="sourceLineNo">045</span>         * <a name="line.45"></a>
<span class="sourceLineNo">046</span>         * &lt;code&gt;<a name="line.46"></a>
<span class="sourceLineNo">047</span>         * Matcher m = httpErrorPattern.matcher("[..] &lt;title&gt;503 Service Unavailable&lt;/title&gt; [..]");<a name="line.47"></a>
<span class="sourceLineNo">048</span>         * if (m.matches()) {<a name="line.48"></a>
<span class="sourceLineNo">049</span>         *              System.out.println("HTTP Error: " + m.group(1);<a name="line.49"></a>
<span class="sourceLineNo">050</span>         * }<a name="line.50"></a>
<span class="sourceLineNo">051</span>         * &lt;/code&gt;<a name="line.51"></a>
<span class="sourceLineNo">052</span>         */<a name="line.52"></a>
<span class="sourceLineNo">053</span>        protected static Pattern httpErrorPattern = Pattern.compile(".*&lt;title&gt;(.*)&lt;/title&gt;.*", Pattern.DOTALL);<a name="line.53"></a>
<span class="sourceLineNo">054</span>        <a name="line.54"></a>
<span class="sourceLineNo">055</span>        <a name="line.55"></a>
<span class="sourceLineNo">056</span>        /**<a name="line.56"></a>
<span class="sourceLineNo">057</span>         * Trace the exception source within the exceptions to identify the originating endpoint. The message<a name="line.57"></a>
<span class="sourceLineNo">058</span>         * of the provided exception is adapted to "@ endpoint.getId() - %orginalMessage".&lt;p&gt;<a name="line.58"></a>
<span class="sourceLineNo">059</span>         * <a name="line.59"></a>
<span class="sourceLineNo">060</span>         * Note that in addition HTTP error codes are extracted from the title, if the exception resulted from<a name="line.60"></a>
<span class="sourceLineNo">061</span>         * an HTTP error, such as for instance "503 Service unavailable"<a name="line.61"></a>
<span class="sourceLineNo">062</span>         * <a name="line.62"></a>
<span class="sourceLineNo">063</span>         * @param conn<a name="line.63"></a>
<span class="sourceLineNo">064</span>         *                      the connection to identify the the endpoint<a name="line.64"></a>
<span class="sourceLineNo">065</span>         * @param ex<a name="line.65"></a>
<span class="sourceLineNo">066</span>         *                      the exception<a name="line.66"></a>
<span class="sourceLineNo">067</span>         * @param additionalInfo<a name="line.67"></a>
<span class="sourceLineNo">068</span>         *                      additional information that might be helpful, e.g. the subquery<a name="line.68"></a>
<span class="sourceLineNo">069</span>         * <a name="line.69"></a>
<span class="sourceLineNo">070</span>         * @return<a name="line.70"></a>
<span class="sourceLineNo">071</span>         *                      a modified exception with endpoint source<a name="line.71"></a>
<span class="sourceLineNo">072</span>         */<a name="line.72"></a>
<span class="sourceLineNo">073</span>        public static QueryEvaluationException traceExceptionSource(RepositoryConnection conn, QueryEvaluationException ex, String additionalInfo) {<a name="line.73"></a>
<span class="sourceLineNo">074</span>                <a name="line.74"></a>
<span class="sourceLineNo">075</span>                Endpoint e = EndpointManager.getEndpointManager().getEndpoint(conn);<a name="line.75"></a>
<span class="sourceLineNo">076</span>                <a name="line.76"></a>
<span class="sourceLineNo">077</span>                String eID;<a name="line.77"></a>
<span class="sourceLineNo">078</span>                <a name="line.78"></a>
<span class="sourceLineNo">079</span>                if (e==null) {<a name="line.79"></a>
<span class="sourceLineNo">080</span>                        log.warn("No endpoint found for connection, probably changed from different thread.");<a name="line.80"></a>
<span class="sourceLineNo">081</span>                        eID = "unknown";<a name="line.81"></a>
<span class="sourceLineNo">082</span>                } else {<a name="line.82"></a>
<span class="sourceLineNo">083</span>                        eID = e.getId();<a name="line.83"></a>
<span class="sourceLineNo">084</span>                }<a name="line.84"></a>
<span class="sourceLineNo">085</span>                <a name="line.85"></a>
<span class="sourceLineNo">086</span>                // check for http error code (heuristic)<a name="line.86"></a>
<span class="sourceLineNo">087</span>                String message = ex.getMessage();<a name="line.87"></a>
<span class="sourceLineNo">088</span>                message = message==null ? "n/a" : message;<a name="line.88"></a>
<span class="sourceLineNo">089</span>                Matcher m = httpErrorPattern.matcher(message);<a name="line.89"></a>
<span class="sourceLineNo">090</span>                if (m.matches()) {<a name="line.90"></a>
<span class="sourceLineNo">091</span>                        log.error("HTTP error detected for endpoint " + eID + ":\n" + message);<a name="line.91"></a>
<span class="sourceLineNo">092</span>                        message = "HTTP Error: " + m.group(1);<a name="line.92"></a>
<span class="sourceLineNo">093</span>                } else {<a name="line.93"></a>
<span class="sourceLineNo">094</span>                        log.info("No http error found");<a name="line.94"></a>
<span class="sourceLineNo">095</span>                }<a name="line.95"></a>
<span class="sourceLineNo">096</span><a name="line.96"></a>
<span class="sourceLineNo">097</span>                <a name="line.97"></a>
<span class="sourceLineNo">098</span>                QueryEvaluationException res = new QueryEvaluationException("@ " + eID + " - " + message + ". " + additionalInfo, ex.getCause());<a name="line.98"></a>
<span class="sourceLineNo">099</span>                res.setStackTrace(ex.getStackTrace());<a name="line.99"></a>
<span class="sourceLineNo">100</span>                return res;<a name="line.100"></a>
<span class="sourceLineNo">101</span>        }<a name="line.101"></a>
<span class="sourceLineNo">102</span>        <a name="line.102"></a>
<span class="sourceLineNo">103</span>        <a name="line.103"></a>
<span class="sourceLineNo">104</span>        /**<a name="line.104"></a>
<span class="sourceLineNo">105</span>         * Repair the connection and then trace the exception source.<a name="line.105"></a>
<span class="sourceLineNo">106</span>         * <a name="line.106"></a>
<span class="sourceLineNo">107</span>         * @param conn<a name="line.107"></a>
<span class="sourceLineNo">108</span>         * @param ex<a name="line.108"></a>
<span class="sourceLineNo">109</span>         * @return<a name="line.109"></a>
<span class="sourceLineNo">110</span>         */<a name="line.110"></a>
<span class="sourceLineNo">111</span>        public static QueryEvaluationException traceExceptionSourceAndRepair(RepositoryConnection conn, QueryEvaluationException ex, String additionalInfo) {<a name="line.111"></a>
<span class="sourceLineNo">112</span>                repairConnection(conn, ex);<a name="line.112"></a>
<span class="sourceLineNo">113</span>                return traceExceptionSource(conn, ex, additionalInfo);<a name="line.113"></a>
<span class="sourceLineNo">114</span>        }<a name="line.114"></a>
<span class="sourceLineNo">115</span>        <a name="line.115"></a>
<span class="sourceLineNo">116</span>        /**<a name="line.116"></a>
<span class="sourceLineNo">117</span>         * Walk the stack trace and in case of SocketException repair the connection of the<a name="line.117"></a>
<span class="sourceLineNo">118</span>         * particular endpoint.<a name="line.118"></a>
<span class="sourceLineNo">119</span>         * <a name="line.119"></a>
<span class="sourceLineNo">120</span>         * @param conn<a name="line.120"></a>
<span class="sourceLineNo">121</span>         *                      the connection to identify the endpoint<a name="line.121"></a>
<span class="sourceLineNo">122</span>         * @param ex<a name="line.122"></a>
<span class="sourceLineNo">123</span>         *                      the exception<a name="line.123"></a>
<span class="sourceLineNo">124</span>         * <a name="line.124"></a>
<span class="sourceLineNo">125</span>         * @throws FedXRuntimeException<a name="line.125"></a>
<span class="sourceLineNo">126</span>         *                              if the connection could not be repaired<a name="line.126"></a>
<span class="sourceLineNo">127</span>         */<a name="line.127"></a>
<span class="sourceLineNo">128</span>        public static void repairConnection(RepositoryConnection conn, Exception ex) throws FedXQueryException, FedXRuntimeException {<a name="line.128"></a>
<span class="sourceLineNo">129</span><a name="line.129"></a>
<span class="sourceLineNo">130</span>                Throwable cause = ex.getCause();<a name="line.130"></a>
<span class="sourceLineNo">131</span>                while (cause != null) {<a name="line.131"></a>
<span class="sourceLineNo">132</span>                        if (cause instanceof SocketException) {<a name="line.132"></a>
<span class="sourceLineNo">133</span>                                try {<a name="line.133"></a>
<span class="sourceLineNo">134</span>                                        Endpoint e = EndpointManager.getEndpointManager().getEndpoint(conn);<a name="line.134"></a>
<span class="sourceLineNo">135</span>                                        EndpointManager.getEndpointManager().repairAllConnections();<a name="line.135"></a>
<span class="sourceLineNo">136</span>                                        throw new FedXQueryException("Socket exception occured for endpoint " + getExceptionString(e==null?"unknown":e.getId(), ex) + ", all connections have been repaired. Query processing of the current query is aborted.", cause);<a name="line.136"></a>
<span class="sourceLineNo">137</span>                                } catch (RepositoryException e) {<a name="line.137"></a>
<span class="sourceLineNo">138</span>                                        log.error("Connection could not be repaired: ", e);<a name="line.138"></a>
<span class="sourceLineNo">139</span>                                        throw new FedXRuntimeException(e.getMessage(), e);<a name="line.139"></a>
<span class="sourceLineNo">140</span>                                }                               <a name="line.140"></a>
<span class="sourceLineNo">141</span>                        }<a name="line.141"></a>
<span class="sourceLineNo">142</span>                        cause = cause.getCause();<a name="line.142"></a>
<span class="sourceLineNo">143</span>                }<a name="line.143"></a>
<span class="sourceLineNo">144</span>        }<a name="line.144"></a>
<span class="sourceLineNo">145</span>        <a name="line.145"></a>
<span class="sourceLineNo">146</span>        /**<a name="line.146"></a>
<span class="sourceLineNo">147</span>         * Return the exception in a convenient representation, i.e. '%msg% (%CLASS%): %ex.getMessage()%'<a name="line.147"></a>
<span class="sourceLineNo">148</span>         * <a name="line.148"></a>
<span class="sourceLineNo">149</span>         * @param msg<a name="line.149"></a>
<span class="sourceLineNo">150</span>         * @param ex<a name="line.150"></a>
<span class="sourceLineNo">151</span>         * <a name="line.151"></a>
<span class="sourceLineNo">152</span>         * @return<a name="line.152"></a>
<span class="sourceLineNo">153</span>         *              the exception in a convenient representation<a name="line.153"></a>
<span class="sourceLineNo">154</span>         */<a name="line.154"></a>
<span class="sourceLineNo">155</span>        public static String getExceptionString(String msg, Exception ex) {<a name="line.155"></a>
<span class="sourceLineNo">156</span>                return msg + " " + ex.getClass().getSimpleName() + ": " + ex.getMessage();<a name="line.156"></a>
<span class="sourceLineNo">157</span>        }<a name="line.157"></a>
<span class="sourceLineNo">158</span>        <a name="line.158"></a>
<span class="sourceLineNo">159</span>        <a name="line.159"></a>
<span class="sourceLineNo">160</span>        /**<a name="line.160"></a>
<span class="sourceLineNo">161</span>         * If possible change the message text of the specified exception. This is only possible<a name="line.161"></a>
<span class="sourceLineNo">162</span>         * if the provided exception has a public constructor with String and Throwable as argument.<a name="line.162"></a>
<span class="sourceLineNo">163</span>         * The new message is set to 'msgPrefix. ex.getMessage()', all other exception elements <a name="line.163"></a>
<span class="sourceLineNo">164</span>         * remain the same.<a name="line.164"></a>
<span class="sourceLineNo">165</span>         * <a name="line.165"></a>
<span class="sourceLineNo">166</span>         * @param &lt;E&gt;<a name="line.166"></a>
<span class="sourceLineNo">167</span>         * @param msgPrefix<a name="line.167"></a>
<span class="sourceLineNo">168</span>         * @param ex<a name="line.168"></a>
<span class="sourceLineNo">169</span>         * @param exClazz<a name="line.169"></a>
<span class="sourceLineNo">170</span>         * <a name="line.170"></a>
<span class="sourceLineNo">171</span>         * @return<a name="line.171"></a>
<span class="sourceLineNo">172</span>         */<a name="line.172"></a>
<span class="sourceLineNo">173</span>        public static &lt;E extends Exception&gt; E changeExceptionMessage(String msgPrefix, E ex, Class&lt;E&gt; exClazz) {<a name="line.173"></a>
<span class="sourceLineNo">174</span>                <a name="line.174"></a>
<span class="sourceLineNo">175</span>                Constructor&lt;E&gt; constructor = null;<a name="line.175"></a>
<span class="sourceLineNo">176</span>                <a name="line.176"></a>
<span class="sourceLineNo">177</span>                try {<a name="line.177"></a>
<span class="sourceLineNo">178</span>                        // try to find the constructor 'public Exception(String, Throwable)'<a name="line.178"></a>
<span class="sourceLineNo">179</span>                        constructor = exClazz.getConstructor(new Class&lt;?&gt;[] {String.class, Throwable.class});<a name="line.179"></a>
<span class="sourceLineNo">180</span>                } catch (SecurityException e) {<a name="line.180"></a>
<span class="sourceLineNo">181</span>                        log.warn("Cannot change the message of exception class " + exClazz.getCanonicalName() + " due to SecurityException: " + e.getMessage());<a name="line.181"></a>
<span class="sourceLineNo">182</span>                        return ex;<a name="line.182"></a>
<span class="sourceLineNo">183</span>                } catch (NoSuchMethodException e) {<a name="line.183"></a>
<span class="sourceLineNo">184</span>                        log.warn("Cannot change the message of exception class " + exClazz.getCanonicalName() + ": Constructor &lt;String, Throwable&gt; not found.");<a name="line.184"></a>
<span class="sourceLineNo">185</span>                        return ex;<a name="line.185"></a>
<span class="sourceLineNo">186</span>                }<a name="line.186"></a>
<span class="sourceLineNo">187</span>                <a name="line.187"></a>
<span class="sourceLineNo">188</span>                <a name="line.188"></a>
<span class="sourceLineNo">189</span>                E newEx;<a name="line.189"></a>
<span class="sourceLineNo">190</span>                try {<a name="line.190"></a>
<span class="sourceLineNo">191</span>                        newEx = constructor.newInstance(new Object[] {msgPrefix + "." + ex.getMessage(), ex.getCause()});<a name="line.191"></a>
<span class="sourceLineNo">192</span>                } catch (Exception e) {<a name="line.192"></a>
<span class="sourceLineNo">193</span>                        log.warn("Cannot change the message of exception class " + exClazz.getCanonicalName() + " due to " + e.getClass().getSimpleName() + ": " + e.getMessage());<a name="line.193"></a>
<span class="sourceLineNo">194</span>                        return ex;<a name="line.194"></a>
<span class="sourceLineNo">195</span>                }<a name="line.195"></a>
<span class="sourceLineNo">196</span>                newEx.setStackTrace(ex.getStackTrace());<a name="line.196"></a>
<span class="sourceLineNo">197</span>                <a name="line.197"></a>
<span class="sourceLineNo">198</span>                return newEx;<a name="line.198"></a>
<span class="sourceLineNo">199</span>        }<a name="line.199"></a>
<span class="sourceLineNo">200</span>}<a name="line.200"></a>




























































</pre>
</div>
</body>
</html>
