java.lang.IllegalArgumentException: Cannot format given Object as a Date

【异常报错提示】：
org.apache.jasper.JasperException: Cannot format given Object as a Date
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:254)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:295)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:241)
javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
root cause

java.lang.IllegalArgumentException: Cannot format given Object as a Date
java.text.DateFormat.format(Unknown Source)
java.text.Format.format(Unknown Source)
com.lyang.governmentbill.CCI.jsp.Bean.ReportManagerBean.reportManagerBean(ReportManagerBean.java:115)
org.apache.jsp.reportList_jsp._jspService(reportList_jsp.java:141)
org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:137)
javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:210)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:295)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:241)
javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
note The full stack trace of the root cause is available in the Apache Tomcat/5.5.17 logs.
【异常处理】
Apache Tomcat/5.5.17
ReportManagerBean.java:115行代码如下：

String begin=sdf.format(begintime);

注：sdf为：SimpleDateFormat sdf=new SimpleDateFormat("yyyy年MM月dd日");

    begintime 为：String begintime=request.getParameter("begintime");

传值是对象不是日期类型 将begintime 转化一下

将String begin=sdf.format(begintime); 改为：String begin=sdf.format(DateFormat.getDateInstance().parse(begintime)); 就好了。SimpleDateFormat 的format方法是：public final java.lang.String format(java.util,Date org0); format方法应该传一个Date类型的参数，而不是String 或者是其它的。


//new Date().toString()可以获得一个本机的现在时间，new Date()是一种时间类型
//new java.text.SimpleDateFormat(
                //"yyyy-MM-dd hh:mm:ss").format(new Date())格式化的是时间类型 如new Date()，如果是一个String类型，需要先转化，方法为
//DateFormat.getDateInstance().parse(begintime)其中begintime是String类型