Program: 20137
Project: 20137
Buggy source:
public updateCheck(Boolean performInBackground){
  if (performInBackground) {
    backgroundTask=true;
  }
 else {
    backgroundTask=false;
  }
  Calendar cal=Calendar.getInstance();
  SimpleDateFormat sdfCheck=new SimpleDateFormat("String_Node_Str");
  String UpdateCheckToday=sdfCheck.format(cal.getTime()).toString();
  if (backgroundTask && new File(paginaEPUBChecker.path_LastUpdateCheckFile).exists()) {
    String UpdateCheckLast=null;
    try {
      UpdateCheckLast=readFileAsString(paginaEPUBChecker.path_LastUpdateCheckFile);
    }
 catch (    IOException e) {
      e.printStackTrace();
    }
    if (Integer.parseInt(UpdateCheckLast) == Integer.parseInt(UpdateCheckToday) && UpdateCheckLast != null) {
      return;
    }
  }
  mainGUI.statusBar.update(paginaEPUBChecker.loadingIcon,__("String_Node_Str"));
  mainGUI.statusBar.update(paginaEPUBChecker.loadingIcon,__("String_Node_Str"));
  try {
    NetTest internetTest=new NetTest("String_Node_Str");
    boolean hasInternetConnection=internetTest.testInternetConnection();
    if (hasInternetConnection == false) {
      errorInternetConnectionNotAvailable();
      return;
    }
  }
 catch (  MalformedURLException e1) {
    errorUpdateCheck(e1);
    return;
  }
  mainGUI.statusBar.update(paginaEPUBChecker.loadingIcon,__("String_Node_Str"));
  try {
    NetTest updateserverTest=new NetTest(updateCheckURL);
    boolean updateserverReady=updateserverTest.testWebsiteConnection(NetTest.HTTP_OK);
    if (updateserverReady == false) {
      errorUpdateServerNotAvailable();
      return;
    }
  }
 catch (  MalformedURLException e2) {
    errorUpdateCheck(e2);
    return;
  }
  mainGUI.statusBar.update(paginaEPUBChecker.loadingIcon,__("String_Node_Str"));
  DocumentBuilderFactory domFactory=DocumentBuilderFactory.newInstance();
  domFactory.setNamespaceAware(true);
  try {
    builder=domFactory.newDocumentBuilder();
    XPathFactory factory=XPathFactory.newInstance();
    xpath=factory.newXPath();
    writeStringToFile(paginaEPUBChecker.path_LastUpdateCheckFile,UpdateCheckToday);
    String[] UpdateInfo=retrieve_UpdateInfo(paginaEPUBChecker.os_name);
    if (Integer.parseInt(paginaEPUBChecker.PROGRAMVERSION.replace("String_Node_Str","String_Node_Str")) < Integer.parseInt(UpdateInfo[0].replace("String_Node_Str","String_Node_Str"))) {
      mainGUI.statusBar.reset();
      messageGUI msg=new messageGUI();
      int answer=msg.showQuestion(__("String_Node_Str").replaceAll("String_Node_Str",UpdateInfo[0]) + "String_Node_Str" + __("String_Node_Str").replaceAll("String_Node_Str",paginaEPUBChecker.PROGRAMVERSION)+ "String_Node_Str"+ __("String_Node_Str").replaceAll("String_Node_Str",UpdateInfo[0])+ "String_Node_Str"+ UpdateInfo[3]+ "String_Node_Str"+ __("String_Node_Str"));
      if (answer == JOptionPane.YES_OPTION) {
        dlgui=new FileDownloader(UpdateInfo[2],System.getProperty("String_Node_Str") + File.separator + "String_Node_Str",String.format(__("String_Node_Str"),UpdateInfo[0],UpdateInfo[1],paginaEPUBChecker.PROGRAMVERSION,paginaEPUBChecker.VERSIONDATE));
      }
 else {
        return;
      }
    }
 else {
      if (backgroundTask) {
        mainGUI.statusBar.update(null,__("String_Node_Str"));
      }
 else {
        messageGUI msg=new messageGUI();
        mainGUI.statusBar.reset();
        msg.showMessage(__("String_Node_Str"),__("String_Node_Str"));
      }
      return;
    }
  }
 catch (  Exception e) {
    errorUpdateCheck(e);
    return;
  }
}

Fixed version (ground truth):
public updateCheck(Boolean performInBackground){
  if (performInBackground) {
    backgroundTask=true;
  }
 else {
    backgroundTask=false;
  }
  Calendar cal=Calendar.getInstance();
  SimpleDateFormat sdfCheck=new SimpleDateFormat("String_Node_Str");
  String UpdateCheckToday=sdfCheck.format(cal.getTime()).toString();
  if (backgroundTask && new File(paginaEPUBChecker.path_LastUpdateCheckFile).exists()) {
    String UpdateCheckLast=null;
    try {
      UpdateCheckLast=readFileAsString(paginaEPUBChecker.path_LastUpdateCheckFile);
    }
 catch (    IOException e) {
      e.printStackTrace();
    }
    if (Integer.parseInt(UpdateCheckLast) == Integer.parseInt(UpdateCheckToday) && UpdateCheckLast != null) {
      return;
    }
  }
  mainGUI.statusBar.update(paginaEPUBChecker.loadingIcon,__("String_Node_Str"));
  mainGUI.statusBar.update(paginaEPUBChecker.loadingIcon,__("String_Node_Str"));
  try {
    NetTest internetTest=new NetTest("String_Node_Str");
    boolean hasInternetConnection=internetTest.testInternetConnection();
    if (hasInternetConnection == false) {
      errorInternetConnectionNotAvailable();
      return;
    }
  }
 catch (  MalformedURLException e1) {
    errorUpdateCheck(e1);
    return;
  }
  mainGUI.statusBar.update(paginaEPUBChecker.loadingIcon,__("String_Node_Str"));
  try {
    NetTest updateserverTest=new NetTest(updateCheckURL);
    boolean updateserverReady=updateserverTest.testWebsiteConnection(NetTest.HTTP_OK);
    if (updateserverReady == false) {
      errorUpdateServerNotAvailable();
      return;
    }
  }
 catch (  MalformedURLException e2) {
    errorUpdateCheck(e2);
    return;
  }
  mainGUI.statusBar.update(paginaEPUBChecker.loadingIcon,__("String_Node_Str"));
  DocumentBuilderFactory domFactory=DocumentBuilderFactory.newInstance();
  domFactory.setNamespaceAware(true);
  try {
    builder=domFactory.newDocumentBuilder();
    XPathFactory factory=XPathFactory.newInstance(XPathFactory.DEFAULT_OBJECT_MODEL_URI,"String_Node_Str",ClassLoader.getSystemClassLoader());
    xpath=factory.newXPath();
    writeStringToFile(paginaEPUBChecker.path_LastUpdateCheckFile,UpdateCheckToday);
    String[] UpdateInfo=retrieve_UpdateInfo(paginaEPUBChecker.os_name);
    if (Integer.parseInt(paginaEPUBChecker.PROGRAMVERSION.replace("String_Node_Str","String_Node_Str")) < Integer.parseInt(UpdateInfo[0].replace("String_Node_Str","String_Node_Str"))) {
      mainGUI.statusBar.reset();
      messageGUI msg=new messageGUI();
      int answer=msg.showQuestion(__("String_Node_Str").replaceAll("String_Node_Str",UpdateInfo[0]) + "String_Node_Str" + __("String_Node_Str").replaceAll("String_Node_Str",paginaEPUBChecker.PROGRAMVERSION)+ "String_Node_Str"+ __("String_Node_Str").replaceAll("String_Node_Str",UpdateInfo[0])+ "String_Node_Str"+ UpdateInfo[3]+ "String_Node_Str"+ __("String_Node_Str"));
      if (answer == JOptionPane.YES_OPTION) {
        dlgui=new FileDownloader(UpdateInfo[2],System.getProperty("String_Node_Str") + File.separator + "String_Node_Str",String.format(__("String_Node_Str"),UpdateInfo[0],UpdateInfo[1],paginaEPUBChecker.PROGRAMVERSION,paginaEPUBChecker.VERSIONDATE));
      }
 else {
        return;
      }
    }
 else {
      if (backgroundTask) {
        mainGUI.statusBar.update(null,__("String_Node_Str"));
      }
 else {
        messageGUI msg=new messageGUI();
        mainGUI.statusBar.reset();
        msg.showMessage(__("String_Node_Str"),__("String_Node_Str"));
      }
      return;
    }
  }
 catch (  Exception e) {
    errorUpdateCheck(e);
    return;
  }
}