关于Jfreechat的问题

是不是Jfreechat默认只能产生6个，能不是改大默认的值，如果可以如何改呢？我的代码是 dataset.setValue(rs.getString("id"),Integer.parseInt(rs.getString("c_name")));
我把数据库的记录扩大到6个以上就会出现
java.lang.ArrayIndexOutOfBoundsException: 6
org.apache.jsp._22_jsp._jspService(_22_jsp.java:155)
org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:97)
javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:334)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:314)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:264)
javax.servlet.http.HttpServlet.service(HttpServlet.java:802)