HttpServletResponse输出乱码的问题

HttpServletResponse的字节流:response.getOutputStream().write()

中文乱码解决:

//通过Content-Type响应头,通知浏览器以何种编码格式打开内容
response.setHeader("Content-Type", "text/html;charset=UTF-8");
String data = "中国";
OutputStream out = response.getOutputStream();
//前后格式要统一,getBytes()不指定编码格式时使用平台默认编码格式
out.write(data.getBytes("UTF-8"));

可以回写<meta>标签来控制浏览器解析行为

String data = "中国";
OutputStream out = response.getOutputStream();

String meta = "<meta http-equiv='content-type' content='text/html;charset=UTF-8' />":
out.write(meta.getBtyes());
out.write(data.getBytes("UTF-8"));

数字乱码:

//通过Content-Type响应头,指定响应内容格式及所采用的编码格式
response.setHeader("Content-Type", "text/html;charset=UTF-8");
String data = "中国";
OutputStream out = response.getOutputStream();
//输出数字:要先把数字转为字符串再getBytes(),否则浏览器会将原数字按指定码表解析出其它内容,而不会输出原数字
out.write((3 + "").getBtyes());

HttpServletResponse的字符流:response.getWriter().write()

//指定响应以UTF-8格式编码内容
response.setCharacterEncoding("UTF-8");
//通知浏览器以何种编码格式打开内容
response.setHeader("Content-Type", "text/html;charset=UTF-8");
//或response.setContentType("text/html;charset=UTF-8");
String data = "中国";
OutputStream out = response.getWriter();
out.write(data);

//response.setContentType("text/html;charset=UTF-8")
//效果等价于setCharacterEncoding("UTF-8")及setHeader("Content-Type","text/html;charset=UTF-8")
response.setContentType("text/html;charset=UTF-8");
String data = "中国";
OutputStream out = response.getWriter();
out.write(data);

不可同时调用getOutputStream()及getWriter()方法,否则将会报错:java.lang.IllegalStateException