static SimpleBody create(final String body, final ContentType contentType) {
        Args.notNull(body, "Body");
        if (body.length() > 2048) {
            return new SimpleBody(null, body, contentType);
        }
        final Charset charset = (contentType != null ? contentType : ContentType.DEFAULT_TEXT).getCharset();
        final byte[] bytes = body.getBytes(charset != null ? charset : StandardCharsets.US_ASCII);
        return new SimpleBody(bytes, null, contentType);
    }
Message body representation as a simple text string or an array of bytes.

@since 5.0
httpclient5/src/main/java/org/apache/hc/client5/http/async/methods/SimpleBody.java