Problem with the old version of xercesImpl.jar

Created August 11, 2016 13:44

Hello,

As i am working with reading and writing of XML file and i am using classes available under the package org.w3c.dom.*. MPS have xercesImpl.jar available under lib folder which is getting loaded when i start MPS. Cause of this i am getting NoSuchMethodException for the code as below.

DOMImplementationLSdomImplementation=(DOMImplementationLS)doc.getImplementation();
LSSerializerlsSerializer=domImplementation.createLSSerializer();

When i use xercesImpl-2.6.1.jar specific to my Solution the problem resolves. Is there any specific reason ,
MPS using a older version of xercesImpl? I guises many will be using org.w3c.dom.*(As comes with JDK) and availability of xercesImpl.jar in the lib folder is problematic, unless MPS changes the current class loader implementation.

As i can see many issues are logged related to the same:
eg: https://mps-support.jetbrains.com/hc/en-us/community/posts/206614495-Java-Class-Cast-Exception-in-MPS-Class-Loader-Issue-

Please share if anybody have information about this.

Thanks & Regards,
Sanjit Kumar Mishra

4 comments

Permanently deleted user

Created August 11, 2016 13:47

I have also experienced this issue. I have used the ClassLoader trick as a workaround but I definitely think this issue should be solved.

Sanjit Mishra

Created August 12, 2016 04:25

@Federico Tomassetti: ClassLoader trick does not work always example:

//////////////////////////// CODE COMENT //////////////////////////////

//This coding is correct but will not work with current MPS//

//////////////////////////////////////////////////////////////////////////////////////

ClassLoader cl=Thread.currentThread().getContextClassLoader(); 
try{ 
 Thread.currentThread().setContextClassLoader(SequenceDiagramTestUtil.class.getClassLoader()); 
DocumentBuilderFactory dbFactory = DocumentBuilderFactory.newInstance(); 
DocumentBuilder dBuilder = dbFactory.newDocumentBuilder(); 
Document doc = dBuilder.newDocument(); 
DOMImplementationLS domImplementation = (DOMImplementationLS)doc.getImplementation();

// Creating document object logic goes here

TransformerFactory tFactory = TransformerFactory.newInstance();
 Transformer transformer = tFactory.newTransformer();

DOMSource source = new DOMSource(document);
 StreamResult result = new StreamResult(System.out);
 transformer.transform(source, result);
}
catch(IOExceptionio e){ 
    ioe.printStackTrace(); 
}
catch(ParserConfigurationException pcee){ 
    pcee.printStackTrace(); 
}
finally{ 
    Thread.currentThread().setContextClassLoader(cl); 
}

To make it work we have to use DOMImplementationLS or any other implementation which converts dom to xml file.

Permanently deleted user

Created August 16, 2016 05:21

Following works for me on MPS 3.3.5

private void createDocument()throws ParserConfigurationException,IOException,SAXException{ 
  File file=new File(path); 
  ClassLoader cl=Thread.currentThread().getContextClassLoader(); 
  try{ 
    Thread.currentThread().setContextClassLoader(this.getClass().getClassLoader()); 
    DocumentBuilderFactory documentBuilderFactory=DocumentBuilderFactory.newInstance(); 
    document=documentBuilderFactory.newDocumentBuilder().parse(file); 
  }finally{ 
    Thread.currentThread().setContextClassLoader(cl); 
  } 
}

Sanjit Mishra

Created August 16, 2016 06:30

@m sch95: Yes this is the class loader trick to avoid Class cast exception but there are other problems as i discussed in my question and one of the comment related to xercesImpl.jar implementation in MPS.

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