ColTypes contents 'coro' then show the IndexOutOfBoundsExcep

my connection like this

[code]public class common_info_connector extends ThreadSafeConnectorServlet{

@Override
protected void configure(HttpServletRequest req, HttpServletResponse res) {
	Connection conn= ( new DataBaseConnection()).getConnection();
	GridConnector c = new GridConnector(conn);
	c.servlet(req, res);
	String type=req.getParameter("type");
	c.dynamic_loading(100);
	c.event.attach(new common_info_Behavior());
	String sql="isindex,new,isshow,ishead,title,fcolor,font,fstyle,content_text,short_content,img,sender,sdate,times,sort_index,type";
	if(c.is_select_mode()){
		c.render_sql("select id,"+sql+" from common_info where type='"+type+"' order by sdate desc", "id", sql);
	}else{
		c.render_sql("select id,"+sql+" from common_info", "id", sql);
		//c.render_table("common_info", "id", sql);
	}
}

}[/code]
and my html like this

mygrid.setHeader("0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15"); mygrid.setInitWidths("50,50,50,50,150,50,50,50,100,100,100,70,70,70,70,0"); mygrid.setColTypes("ch,ch,ch,ch,txt,co,co,co,ed,txt,ed,ed,ro,ed,ed,ed");
exception will be throw

java.lang.IndexOutOfBoundsException: Index: 5, Size: 0 at java.util.ArrayList.RangeCheck(ArrayList.java:547) at java.util.ArrayList.get(ArrayList.java:322) at com.dhtmlx.connector.GridConnector.resolve_parameter(GridConnector.java:171) at com.dhtmlx.connector.GridConnector.fill_collections(GridConnector.java:97) at com.dhtmlx.connector.GridConnector.parse_request(GridConnector.java:75) at com.dhtmlx.connector.BaseConnector.is_select_mode(BaseConnector.java:746) at dhtmlx_connection.common_info_connector.configure(common_info_connector.java:26) at com.dhtmlx.connector.ThreadSafeConnectorServlet.doGet(ThreadSafeConnectorServlet.java:19) at javax.servlet.http.HttpServlet.service(HttpServlet.java:617) at javax.servlet.http.HttpServlet.service(HttpServlet.java:717) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) at com.common.chineseServlet.doFilter(chineseServlet.java:67) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233) at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127) at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102) at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109) at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:293) at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:859) at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:602) at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:489) at java.lang.Thread.run(Thread.java:619)
and i change ‘coro’ to ‘ed’ i will work will
why?
look forward for you help