thrifty-runtime/src/main/java/com/microsoft/thrifty/protocol/JsonProtocol.java
private String readJsonNumericChars() throws IOException {
        StringBuilder strbld = new StringBuilder();
        while (true) {
            byte ch = reader.peek();
            if (!isJsonNumeric(ch)) {
                break;
            }
            strbld.append((char) reader.read());
        }
        return strbld.toString();
    }
private String readJsonNumericChars() throws IOException {
        StringBuilder strbld = new StringBuilder();
        while (true) {
            byte ch = reader.peek();
            if (!isJsonNumeric(ch)) {
                break;
            }
            strbld.append((char) reader.read());
        }
        return strbld.toString();
    }
not do a complete regex check to validate that this is actually a number.