ClassCastException: java.lang.Integer cannot be cast to java.lang.String

最新推荐文章于 2024-03-05 09:01:38 发布

原创最新推荐文章于 2024-03-05 09:01:38 发布 · 382 阅读

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本文探讨了在Servlet中遇到的ClassCastException错误，具体为尝试将Integer类型转换为String类型时引发的问题。通过分析代码片段，我们将深入理解类型转换的正确方式，并提供解决方案。

protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
	PrintWriter out=response.getWriter();
	ServletContext context=this.getServletContext();
	if(context.getAttribute("count")==null){
		context.setAttribute("count", 1);
		String num=(String)context.getAttribute("count");
		out.println(num);
	}else{
		
		Long i=(Long)context.getAttribute("count");
		Integer num2=new Integer(String.valueOf(i));
		
		out.println(num2);
	}

出现下面错误

严重: Servlet.service() for servlet [my1] in context with path [/first] threw exception
java.lang.ClassCastException: java.lang.Integer cannot be cast to java.lang.String
求解答