Getting request payload from POST request in Java servlet

Simple answer:
Use getReader() to read the body of the request

More info:
There are two methods for reading the data in the body:

1. getReader() returns a BufferedReader that will allow you to read the body of the request.

2. getInputStream() returns a ServletInputStream if you need to read binary data.

Note from the docs: "[Either method] may be called to read the body, not both."

String payloadRequest = getBody(request);

Using this method

public static String getBody(HttpServletRequest request) throws IOException {    String body = null;    StringBuilder stringBuilder = new StringBuilder();    BufferedReader bufferedReader = null;    try {        InputStream inputStream = request.getInputStream();        if (inputStream != null) {            bufferedReader = new BufferedReader(new InputStreamReader(inputStream));            char[] charBuffer = new char[128];            int bytesRead = -1;            while ((bytesRead = bufferedReader.read(charBuffer)) > 0) {                stringBuilder.append(charBuffer, 0, bytesRead);            }        } else {            stringBuilder.append("");        }    } catch (IOException ex) {        throw ex;    } finally {        if (bufferedReader != null) {            try {                bufferedReader.close();            } catch (IOException ex) {                throw ex;            }        }    }    body = stringBuilder.toString();    return body;}

You can use Buffer Reader from request to read

    // Read from request    StringBuilder buffer = new StringBuilder();    BufferedReader reader = request.getReader();    String line;    while ((line = reader.readLine()) != null) {        buffer.append(line);        buffer.append(System.lineSeparator());    }    String data = buffer.toString()