Servlet中文乱码setContentType设置无效

这段代码必须在获取response对象之前设置

response.setContentType("text/html;charset=utf-8");

错误示范：

		PrintWriter writer = resp.getWriter();
		//设置请求和相应编码
		req.setCharacterEncoding("utf-8");
		resp.setContentType("text/html;charset=utf-8");

应改为：

//设置请求和相应编码
		req.setCharacterEncoding("utf-8");
		resp.setContentType("text/html;charset=utf-8");
		PrintWriter writer = resp.getWriter();