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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 "License");<a name="line.6"></a>
<FONT color="green">007</FONT> * you may not use this file except in compliance with the License.<a name="line.7"></a>
<FONT color="green">008</FONT> * 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> * $Id: HasPositionalPredChecker.java 468655 2006-10-28 07:12:06Z minchau $<a name="line.19"></a>
<FONT color="green">020</FONT> */<a name="line.20"></a>
<FONT color="green">021</FONT> package org.apache.xpath.axes;<a name="line.21"></a>
<FONT color="green">022</FONT> <a name="line.22"></a>
<FONT color="green">023</FONT> import org.apache.xpath.Expression;<a name="line.23"></a>
<FONT color="green">024</FONT> import org.apache.xpath.ExpressionOwner;<a name="line.24"></a>
<FONT color="green">025</FONT> import org.apache.xpath.XPathVisitor;<a name="line.25"></a>
<FONT color="green">026</FONT> import org.apache.xpath.functions.FuncLast;<a name="line.26"></a>
<FONT color="green">027</FONT> import org.apache.xpath.functions.FuncPosition;<a name="line.27"></a>
<FONT color="green">028</FONT> import org.apache.xpath.functions.Function;<a name="line.28"></a>
<FONT color="green">029</FONT> import org.apache.xpath.objects.XNumber;<a name="line.29"></a>
<FONT color="green">030</FONT> import org.apache.xpath.operations.Div;<a name="line.30"></a>
<FONT color="green">031</FONT> import org.apache.xpath.operations.Minus;<a name="line.31"></a>
<FONT color="green">032</FONT> import org.apache.xpath.operations.Mod;<a name="line.32"></a>
<FONT color="green">033</FONT> import org.apache.xpath.operations.Mult;<a name="line.33"></a>
<FONT color="green">034</FONT> import org.apache.xpath.operations.Plus;<a name="line.34"></a>
<FONT color="green">035</FONT> import org.apache.xpath.operations.Quo;<a name="line.35"></a>
<FONT color="green">036</FONT> import org.apache.xpath.operations.Variable;<a name="line.36"></a>
<FONT color="green">037</FONT> <a name="line.37"></a>
<FONT color="green">038</FONT> public class HasPositionalPredChecker extends XPathVisitor<a name="line.38"></a>
<FONT color="green">039</FONT> {<a name="line.39"></a>
<FONT color="green">040</FONT> private boolean m_hasPositionalPred = false;<a name="line.40"></a>
<FONT color="green">041</FONT> private int m_predDepth = 0;<a name="line.41"></a>
<FONT color="green">042</FONT> <a name="line.42"></a>
<FONT color="green">043</FONT> /**<a name="line.43"></a>
<FONT color="green">044</FONT> * Process the LocPathIterator to see if it contains variables <a name="line.44"></a>
<FONT color="green">045</FONT> * or functions that may make it context dependent.<a name="line.45"></a>
<FONT color="green">046</FONT> * @param path LocPathIterator that is assumed to be absolute, but needs checking.<a name="line.46"></a>
<FONT color="green">047</FONT> * @return true if the path is confirmed to be absolute, false if it <a name="line.47"></a>
<FONT color="green">048</FONT> * may contain context dependencies.<a name="line.48"></a>
<FONT color="green">049</FONT> */<a name="line.49"></a>
<FONT color="green">050</FONT> public static boolean check(LocPathIterator path)<a name="line.50"></a>
<FONT color="green">051</FONT> {<a name="line.51"></a>
<FONT color="green">052</FONT> HasPositionalPredChecker hppc = new HasPositionalPredChecker();<a name="line.52"></a>
<FONT color="green">053</FONT> path.callVisitors(null, hppc);<a name="line.53"></a>
<FONT color="green">054</FONT> return hppc.m_hasPositionalPred;<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> * Visit a function.<a name="line.58"></a>
<FONT color="green">059</FONT> * @param owner The owner of the expression, to which the expression can <a name="line.59"></a>
<FONT color="green">060</FONT> * be reset if rewriting takes place.<a name="line.60"></a>
<FONT color="green">061</FONT> * @param func The function reference object.<a name="line.61"></a>
<FONT color="green">062</FONT> * @return true if the sub expressions should be traversed.<a name="line.62"></a>
<FONT color="green">063</FONT> */<a name="line.63"></a>
<FONT color="green">064</FONT> public boolean visitFunction(ExpressionOwner owner, Function func)<a name="line.64"></a>
<FONT color="green">065</FONT> {<a name="line.65"></a>
<FONT color="green">066</FONT> if((func instanceof FuncPosition) ||<a name="line.66"></a>
<FONT color="green">067</FONT> (func instanceof FuncLast))<a name="line.67"></a>
<FONT color="green">068</FONT> m_hasPositionalPred = true;<a name="line.68"></a>
<FONT color="green">069</FONT> return true;<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> // * Visit a variable reference.<a name="line.73"></a>
<FONT color="green">074</FONT> // * @param owner The owner of the expression, to which the expression can <a name="line.74"></a>
<FONT color="green">075</FONT> // * be reset if rewriting takes place.<a name="line.75"></a>
<FONT color="green">076</FONT> // * @param var The variable reference object.<a name="line.76"></a>
<FONT color="green">077</FONT> // * @return true if the sub expressions should be traversed.<a name="line.77"></a>
<FONT color="green">078</FONT> // */<a name="line.78"></a>
<FONT color="green">079</FONT> // public boolean visitVariableRef(ExpressionOwner owner, Variable var)<a name="line.79"></a>
<FONT color="green">080</FONT> // {<a name="line.80"></a>
<FONT color="green">081</FONT> // m_hasPositionalPred = true;<a name="line.81"></a>
<FONT color="green">082</FONT> // return true;<a name="line.82"></a>
<FONT color="green">083</FONT> // }<a name="line.83"></a>
<FONT color="green">084</FONT> <a name="line.84"></a>
<FONT color="green">085</FONT> /**<a name="line.85"></a>
<FONT color="green">086</FONT> * Visit a predicate within a location path. Note that there isn't a <a name="line.86"></a>
<FONT color="green">087</FONT> * proper unique component for predicates, and that the expression will <a name="line.87"></a>
<FONT color="green">088</FONT> * be called also for whatever type Expression is.<a name="line.88"></a>
<FONT color="green">089</FONT> * <a name="line.89"></a>
<FONT color="green">090</FONT> * @param owner The owner of the expression, to which the expression can <a name="line.90"></a>
<FONT color="green">091</FONT> * be reset if rewriting takes place.<a name="line.91"></a>
<FONT color="green">092</FONT> * @param pred The predicate object.<a name="line.92"></a>
<FONT color="green">093</FONT> * @return true if the sub expressions should be traversed.<a name="line.93"></a>
<FONT color="green">094</FONT> */<a name="line.94"></a>
<FONT color="green">095</FONT> public boolean visitPredicate(ExpressionOwner owner, Expression pred)<a name="line.95"></a>
<FONT color="green">096</FONT> {<a name="line.96"></a>
<FONT color="green">097</FONT> m_predDepth++;<a name="line.97"></a>
<FONT color="green">098</FONT> <a name="line.98"></a>
<FONT color="green">099</FONT> if(m_predDepth == 1)<a name="line.99"></a>
<FONT color="green">100</FONT> {<a name="line.100"></a>
<FONT color="green">101</FONT> if((pred instanceof Variable) || <a name="line.101"></a>
<FONT color="green">102</FONT> (pred instanceof XNumber) ||<a name="line.102"></a>
<FONT color="green">103</FONT> (pred instanceof Div) ||<a name="line.103"></a>
<FONT color="green">104</FONT> (pred instanceof Plus) ||<a name="line.104"></a>
<FONT color="green">105</FONT> (pred instanceof Minus) ||<a name="line.105"></a>
<FONT color="green">106</FONT> (pred instanceof Mod) ||<a name="line.106"></a>
<FONT color="green">107</FONT> (pred instanceof Quo) ||<a name="line.107"></a>
<FONT color="green">108</FONT> (pred instanceof Mult) ||<a name="line.108"></a>
<FONT color="green">109</FONT> (pred instanceof org.apache.xpath.operations.Number) ||<a name="line.109"></a>
<FONT color="green">110</FONT> (pred instanceof Function))<a name="line.110"></a>
<FONT color="green">111</FONT> m_hasPositionalPred = true;<a name="line.111"></a>
<FONT color="green">112</FONT> else<a name="line.112"></a>
<FONT color="green">113</FONT> pred.callVisitors(owner, this);<a name="line.113"></a>
<FONT color="green">114</FONT> }<a name="line.114"></a>
<FONT color="green">115</FONT> <a name="line.115"></a>
<FONT color="green">116</FONT> m_predDepth--;<a name="line.116"></a>
<FONT color="green">117</FONT> <a name="line.117"></a>
<FONT color="green">118</FONT> // Don't go have the caller go any further down the subtree.<a name="line.118"></a>
<FONT color="green">119</FONT> return false;<a name="line.119"></a>
<FONT color="green">120</FONT> }<a name="line.120"></a>
<FONT color="green">121</FONT> <a name="line.121"></a>
<FONT color="green">122</FONT> <a name="line.122"></a>
<FONT color="green">123</FONT> }<a name="line.123"></a>
<FONT color="green">124</FONT> <a name="line.124"></a>
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