Program: 129770
Project: 129770
Buggy source:
public void widgetSelected(SelectionEvent event){
  if (fileFieldXml.getResult() == null) {
    return;
  }
  String text=fileFieldXml.getText();
  if (isContextMode()) {
    ContextType contextType=ConnectionContextHelper.getContextTypeForContextMode(connectionItem.getConnection(),true);
    text=TalendQuoteUtils.removeQuotes(ConnectionContextHelper.getOriginalValue(contextType,text));
  }
  File file=new File(text);
  if (file.exists()) {
    if (file.exists()) {
      if (XmlUtil.isXSDFile(text)) {
        List<ATreeNode> treeNodes=new ArrayList<ATreeNode>();
        try {
          XSDSchema xsdSchema=updateXSDSchema(text);
          List<ATreeNode> list=updateRootNodes(xsdSchema,true);
          if (list.size() > 1) {
            RootNodeSelectDialog dialog=new RootNodeSelectDialog(null,list);
            if (dialog.open() == IDialogConstants.OK_ID) {
              ATreeNode selectedNode=dialog.getSelectedNode();
              valid=treePopulator.populateTree(xsdSchema,selectedNode,treeNodes);
              if (treeNodes.size() > 0) {
                treeNode=treeNodes.get(0);
              }
            }
 else {
              return;
            }
          }
 else {
            valid=treePopulator.populateTree(xsdSchema,list.get(0),treeNodes);
            if (treeNodes.size() > 0) {
              treeNode=treeNodes.get(0);
            }
          }
        }
 catch (        Exception ex) {
          ExceptionHandler.process(ex);
        }
        XmlFileWizard wizard=((XmlFileWizard)getPage().getWizard());
        wizard.setRootNodes(treeNodes);
        wizard.setTreeRootNode(treeNode);
        List<FOXTreeNode> nodeList=getCorrespondingFoxTreeNodes(treeNode,true);
        if (nodeList.size() > 0) {
          FOXTreeNode foxTreeNode=nodeList.get(0);
          EList root=getConnection().getRoot();
          if (root == null)           return;
          XMLFileNode xmlFileNode=ConnectionFactory.eINSTANCE.createXMLFileNode();
          String currentPath="String_Node_Str" + foxTreeNode.getLabel();
          xmlFileNode.setXMLPath(currentPath);
          xmlFileNode.setRelatedColumn(foxTreeNode.getColumnLabel());
          xmlFileNode.setAttribute(foxTreeNode.isMain() ? "String_Node_Str" : "String_Node_Str");
          xmlFileNode.setDefaultValue(foxTreeNode.getDefaultValue());
          xmlFileNode.setType(foxTreeNode.getDataType());
          XMLFileNode originalXmlNode=null;
          if (root.size() > 0) {
            originalXmlNode=(XMLFileNode)root.get(0);
          }
          if (originalXmlNode != null && !currentPath.equals(originalXmlNode.getXMLPath())) {
            wizard.setXsdRootChange(true);
          }
 else {
            wizard.setXsdRootChange(false);
          }
          root.clear();
          root.add(xmlFileNode);
        }
      }
 else {
        valid=treePopulator.populateTree(text,treeNode);
      }
    }
  }
}

Fixed version (ground truth):
public void widgetSelected(SelectionEvent event){
  if (fileFieldXml.getResult() == null) {
    return;
  }
  String text=fileFieldXml.getText();
  if (isContextMode()) {
    ContextType contextType=ConnectionContextHelper.getContextTypeForContextMode(connectionItem.getConnection(),true);
    text=TalendQuoteUtils.removeQuotes(ConnectionContextHelper.getOriginalValue(contextType,text));
  }
  File file=new File(text);
  if (file.exists()) {
    if (file.exists()) {
      if (XmlUtil.isXSDFile(text)) {
        List<ATreeNode> treeNodes=new ArrayList<ATreeNode>();
        try {
          XSDSchema xsdSchema=updateXSDSchema(text);
          List<ATreeNode> list=updateRootNodes(xsdSchema,true);
          if (list.size() > 1) {
            RootNodeSelectDialog dialog=new RootNodeSelectDialog(null,list);
            if (dialog.open() == IDialogConstants.OK_ID) {
              ATreeNode selectedNode=dialog.getSelectedNode();
              valid=treePopulator.populateTree(xsdSchema,selectedNode,treeNodes);
              if (treeNodes.size() > 0) {
                treeNode=treeNodes.get(0);
              }
            }
 else {
              return;
            }
          }
 else {
            valid=treePopulator.populateTree(xsdSchema,list.get(0),treeNodes);
            if (treeNodes.size() > 0) {
              treeNode=treeNodes.get(0);
            }
          }
        }
 catch (        Exception ex) {
          ExceptionHandler.process(ex);
        }
        XmlFileWizard wizard=((XmlFileWizard)getPage().getWizard());
        wizard.setRootNodes(treeNodes);
        wizard.setTreeRootNode(treeNode);
        List<FOXTreeNode> nodeList=getCorrespondingFoxTreeNodes(treeNode,true);
        if (nodeList.size() > 0) {
          FOXTreeNode foxTreeNode=nodeList.get(0);
          EList root=getConnection().getRoot();
          if (root == null)           return;
          XMLFileNode xmlFileNode=ConnectionFactory.eINSTANCE.createXMLFileNode();
          String currentPath="String_Node_Str" + foxTreeNode.getLabel();
          xmlFileNode.setXMLPath(currentPath);
          xmlFileNode.setRelatedColumn(foxTreeNode.getColumnLabel());
          xmlFileNode.setAttribute(foxTreeNode.isMain() ? "String_Node_Str" : "String_Node_Str");
          xmlFileNode.setDefaultValue(foxTreeNode.getDefaultValue());
          xmlFileNode.setType(foxTreeNode.getDataType());
          XMLFileNode originalXmlNode=null;
          if (root.size() > 0) {
            originalXmlNode=(XMLFileNode)root.get(0);
          }
          if (originalXmlNode != null && !currentPath.equals(originalXmlNode.getXMLPath())) {
            wizard.setXsdRootChange(true);
          }
 else {
            wizard.setXsdRootChange(false);
          }
          root.clear();
          root.add(xmlFileNode);
        }
      }
 else {
        valid=treePopulator.populateTree(text,treeNode);
      }
    }
    checkFieldsValue();
  }
}