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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal>Here’s hoping this question gets to the right place. <o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>We are using JDOM2 (2.0.3) and it’s my understanding that instances of XPathExpression are not thread safe. We were using clone as a (hopefully) more efficient method of getting our “own” instance of a pre compiled XPathExpression safe from other thread access. This is not my main question, but is it more efficient?<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>My main question has to do with setting variables on the XPathExpression. I could not get the variable setting to work on a cloned copy of an XPathExpression, but it works if I set the variable before cloning. The problem with this, is of course, thread safety.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Is this a known bug, maybe fixed? <o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>This works (but opens an opportunity for threading problems since we’re using precompiled static instances):<o:p></o:p></p><p class=MsoNormal style='text-autospace:none'><span style='font-size:10.0pt;font-family:Consolas;color:black'> XPathExpression<Element> xPath = </span><i><span style='font-size:10.0pt;font-family:Consolas;color:#0000C0'>pathMap</span></i><span style='font-size:10.0pt;font-family:Consolas;color:black'>.get(method);</span><span style='font-size:10.0pt;font-family:Consolas'><o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><span style='font-size:10.0pt;font-family:Consolas;color:black'> xPath.setVariable(</span><span style='font-size:10.0pt;font-family:Consolas;color:#2A00FF'>"variable"</span><span style='font-size:10.0pt;font-family:Consolas;color:black'>, </span><i><span style='font-size:10.0pt;font-family:Consolas;color:#0000C0'>namespace</span></i><span style='font-size:10.0pt;font-family:Consolas;color:black'>, </span><span style='font-size:10.0pt;font-family:Consolas;color:#2A00FF'>"fString"</span><span style='font-size:10.0pt;font-family:Consolas;color:black'>);</span><span style='font-size:10.0pt;font-family:Consolas'><o:p></o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:Consolas;color:black'> List<Element> elems = xPath.clone().evaluate(model.asDocument());<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:Consolas;color:black'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:Consolas;color:black'>But this doesn’t work, it doesn’t seem to recognize the variable replacement:<o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><span style='font-size:10.0pt;font-family:Consolas;color:black'> XPathExpression<Element> xPath = </span><i><span style='font-size:10.0pt;font-family:Consolas;color:#0000C0'>pathMap</span></i><span style='font-size:10.0pt;font-family:Consolas;color:black'>.get(method).clone();</span><span style='font-size:10.0pt;font-family:Consolas'><o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><span style='font-size:10.0pt;font-family:Consolas;color:black'> xPath.setVariable(</span><span style='font-size:10.0pt;font-family:Consolas;color:#2A00FF'>"variable"</span><span style='font-size:10.0pt;font-family:Consolas;color:black'>, </span><i><span style='font-size:10.0pt;font-family:Consolas;color:#0000C0'>namespace</span></i><span style='font-size:10.0pt;font-family:Consolas;color:black'>, </span><span style='font-size:10.0pt;font-family:Consolas;color:#2A00FF'>"fString"</span><span style='font-size:10.0pt;font-family:Consolas;color:black'>);</span><span style='font-size:10.0pt;font-family:Consolas'><o:p></o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:Consolas;color:black'> List<Element> elems = xPath.evaluate(model.asDocument());<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:Consolas;color:black'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:Consolas;color:black'>pathmap is just a map of precompiled XPathExpressions.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:Consolas;color:black'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:Consolas;color:black'>Thanks,<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:Consolas;color:black'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:Consolas;color:black'>Wayne Keeney<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:Consolas;color:black'>SAT Services</span><o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p></div></body></html>