当我从Servlet doPost方法将逻辑移至自己的类时，出现UnsupportedEncodingException

Question

When I have this code in my servlet doPost method, everything is fine.

@Override
protected void doPost(HttpServletRequest request, HttpServletResponse response)
        throws ServletException, IOException {
...
String data = CharStreams.toString(new InputStreamReader(request.getInputStream(), "UTF-8"));
...
}

I wanted to move this code out to another class, but when I did that I get this error that intellij reports:

java.io.UnsupportedEncodingException

public class SomeUtil {

  public String readFromInput(ServletInputStream is) {

    return CharStreams.toString(new InputStreamReader(is, "UTF-8"));
  }

}

Does the servlet doPost somewhere handle this exception that I can't see?

Answer 1

The doPost() method declares throws ServletException, IOException which covers for the throws UnsupportedEncodingException in the InputStreamReader constructor you are using.

In your readFromInput() method, you could declare a throws clause as well or surround that line in a try-catch block. To avoid the UnsupportedEncodingException , use the constructor that accepts a Charset object and just pass in the standard UTF-8 .