import  javax.servlet.jsp.tagext.TagSupport;

 public   class  TagConfirmWindow  extends  TagSupport{
String jsCode = "<script language=\"JavaScript\">\n" +
            "<!--\n" +
            "  var w = window.open(\"\", \"confirmWindow\", \"width=400, height=200, left=\" + (screen.width - 400) / 2 + \", top=\" + (screen.height - 200) / 2);\n" +
            "  w.document.open();\n" .......
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} 

 public   class  TagConfirmWindow  extends  TagSupport {

   private  String confirmQueryString;
   private  String confirmType;

   public   int  doStartTag() {

     try  {
       if  (!confirmQueryString.equals("")) {
        JspWriter out = pageContext.getOut();
        String jsCode = "<script language=\"JavaScript\">\n" +
            "<!--\n" +
            "  var w = window.open(\"\", \"confirmWindow\", \"width=400, height=200, left=\" + (screen.width - 400) / 2 + \", top=\" + (screen.height - 200) / 2);\n" +
            "  w.document.open();\n" +
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    "//-->\n" +
            "</script>\n";
        out.print(jsCode);
      }
    }  catch  (Exception e) {
      System.out.println("Еrror in TagConfirmWindow: " + e);
    }
     return  (SKIP_BODY);
  }

   public   void  setConfirmQueryString(String confirmQueryString) {
     this .confirmQueryString = confirmQueryString;
  }

   public   void  setConfirmType(String confirmType) {
     this .confirmType = confirmType;
  }

}