DO NOT REPLY [Bug 12486] New: - XPathContext.reset() does unnecessary memory allocations

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http://nagoya.apache.org/bugzilla/show_bug.cgi?id=12486

XPathContext.reset() does unnecessary memory allocations

           Summary: XPathContext.reset() does unnecessary memory allocations
           Product: XalanJ2
           Version: 2.4
          Platform: Other
        OS/Version: Other
            Status: NEW
          Severity: Normal
          Priority: Other
         Component: org.apache.xpath
        AssignedTo: xalan-dev@xml.apache.org
        ReportedBy: Pavel_Ausianik@epam.com


Method XPathContext.reset()  creates many new instances of java objects, 
causing unnecessary memory allocations, instead of reuse previosly created 
objects. 

Examples:
m_dtmManager = DTMManager.newInstance(
                   org.apache.xpath.objects.XMLStringFactoryImpl.getFactory());

Documentation on DTMManager says it should use single instance instead

m_currentExpressionNodes = new int[RECURSIONLIMIT];
// Why don't use previous arrays?

m_currentNodes = new int[RECURSIONLIMIT];
// Why don't use previous arrays?

m_axesIteratorStack = new Stack();
// Why don't call Stack.clear()

m_contextNodeLists = new Stack();
// Why don't call Stack.clear()

Method reset called every time from TransformerImpl.transfrom() method, 
allocating many objects which never used after this call