Program: 20750
Project: 20750
Buggy source:
public void doFree(DownloadLink downloadLink) throws Exception {
  URLConnectionAdapter con=br.openGetConnection(downloadLink.getDownloadURL());
  if (con.getContentType().contains("String_Node_Str")) {
    br.followConnection();
    String dllink=null;
    if (br.containsHTML("String_Node_Str"))     throw new PluginException(LinkStatus.ERROR_FATAL,JDL.L("String_Node_Str","String_Node_Str"));
    String fileID=new Regex(downloadLink.getDownloadURL(),"String_Node_Str").getMatch(0);
    boolean isStream=br.containsHTML("String_Node_Str");
    if (!isStream) {
      Browser brc=requestXML(br,"String_Node_Str" + fileID,null,false);
      if (brc.containsHTML("String_Node_Str")) {
        String error=brc.getRegex("String_Node_Str").getMatch(0);
        if (error == null)         throw new PluginException(LinkStatus.ERROR_PLUGIN_DEFECT);
        if (error.contains("String_Node_Str"))         throw new PluginException(LinkStatus.ERROR_IP_BLOCKED,5 * 60 * 1000l);
        if (error.contains("String_Node_Str"))         throw new PluginException(LinkStatus.ERROR_IP_BLOCKED,30 * 60 * 1000l);
        if (error.contains("String_Node_Str"))         throw new PluginException(LinkStatus.ERROR_TEMPORARILY_UNAVAILABLE,"String_Node_Str",30 * 60 * 1000l);
        throw new PluginException(LinkStatus.ERROR_PLUGIN_DEFECT);
      }
      if (brc.containsHTML("String_Node_Str")) {
        int waitsecs=0;
        String waittime=brc.getRegex("String_Node_Str").getMatch(0);
        if (waittime != null)         waitsecs=Integer.parseInt(waittime);
        if (waitsecs > 0)         sleep(waitsecs * 1000l,downloadLink);
        dllink=brc.getRegex("String_Node_Str").getMatch(0);
      }
    }
 else {
      br.getPage("String_Node_Str" + fileID + "String_Node_Str");
      dllink=br.getRedirectLocation();
    }
    if (dllink == null)     throw new PluginException(LinkStatus.ERROR_PLUGIN_DEFECT);
    if (!dllink.contains("String_Node_Str"))     dllink="String_Node_Str" + dllink;
    br.setDebug(true);
    dl=jd.plugins.BrowserAdapter.openDownload(br,downloadLink,dllink,!isStream,1);
  }
 else {
    con.disconnect();
    dl=jd.plugins.BrowserAdapter.openDownload(br,downloadLink,downloadLink.getDownloadURL(),true,0);
  }
  if (dl.getConnection().getContentType().contains("String_Node_Str")) {
    br.followConnection();
    if (br.containsHTML("String_Node_Str"))     throw new PluginException(LinkStatus.ERROR_TEMPORARILY_UNAVAILABLE,"String_Node_Str");
    throw new PluginException(LinkStatus.ERROR_PLUGIN_DEFECT);
  }
  dl.startDownload();
}

Fixed version (ground truth):
public void doFree(DownloadLink downloadLink) throws Exception {
  URLConnectionAdapter con=br.openGetConnection(downloadLink.getDownloadURL());
  if (con.getContentType().contains("String_Node_Str")) {
    br.followConnection();
    String dllink=null;
    if (br.containsHTML(PREMIUMONLYTEXT))     throw new PluginException(LinkStatus.ERROR_FATAL,JDL.L("String_Node_Str","String_Node_Str"));
    String fileID=new Regex(downloadLink.getDownloadURL(),"String_Node_Str").getMatch(0);
    boolean isStream=br.containsHTML("String_Node_Str");
    if (!isStream) {
      Browser brc=requestXML(br,"String_Node_Str" + fileID,null,false);
      if (brc.containsHTML("String_Node_Str")) {
        String error=brc.getRegex("String_Node_Str").getMatch(0);
        if (error == null)         throw new PluginException(LinkStatus.ERROR_PLUGIN_DEFECT);
        if (error.contains("String_Node_Str"))         throw new PluginException(LinkStatus.ERROR_IP_BLOCKED,5 * 60 * 1000l);
        if (error.contains("String_Node_Str"))         throw new PluginException(LinkStatus.ERROR_IP_BLOCKED,30 * 60 * 1000l);
        if (error.contains("String_Node_Str"))         throw new PluginException(LinkStatus.ERROR_TEMPORARILY_UNAVAILABLE,"String_Node_Str",30 * 60 * 1000l);
        throw new PluginException(LinkStatus.ERROR_PLUGIN_DEFECT);
      }
      if (brc.containsHTML("String_Node_Str")) {
        int waitsecs=0;
        String waittime=brc.getRegex("String_Node_Str").getMatch(0);
        if (waittime != null)         waitsecs=Integer.parseInt(waittime);
        if (waitsecs > 0)         sleep(waitsecs * 1000l,downloadLink);
        dllink=brc.getRegex("String_Node_Str").getMatch(0);
      }
    }
 else {
      br.getPage("String_Node_Str" + fileID + "String_Node_Str");
      dllink=br.getRedirectLocation();
    }
    if (dllink == null)     throw new PluginException(LinkStatus.ERROR_PLUGIN_DEFECT);
    if (!dllink.contains("String_Node_Str"))     dllink="String_Node_Str" + dllink;
    br.setDebug(true);
    dl=jd.plugins.BrowserAdapter.openDownload(br,downloadLink,dllink,!isStream,1);
  }
 else {
    con.disconnect();
    dl=jd.plugins.BrowserAdapter.openDownload(br,downloadLink,downloadLink.getDownloadURL(),true,0);
  }
  if (dl.getConnection().getContentType().contains("String_Node_Str")) {
    br.followConnection();
    if (br.containsHTML("String_Node_Str"))     throw new PluginException(LinkStatus.ERROR_TEMPORARILY_UNAVAILABLE,"String_Node_Str");
    throw new PluginException(LinkStatus.ERROR_PLUGIN_DEFECT);
  }
  dl.startDownload();
}