title: Write ObjectNode to JSON String with UTF-8 Characters to Escaped ASCII
body: <p>I would like to write the contents of Jackson's <code>ObjectNode</code> to a string with the UTF-8 characters written as ASCII (Unicode escaped).</p>
  
  <p>Here is a sample method:
  </p>
  
  <pre><code>private String writeUnicodeString() {
      ObjectMapper mapper = new ObjectMapper();
      ObjectNode node = mapper.getNodeFactory().objectNode();
      node.put("field1", "Maël Hörz");
      return node.toString();
  }
  </code></pre>
  
  <p>By default, this outputs:</p>
  
  <pre><code>{"field1":"Maël Hörz"}
  </code></pre>
  
  <p>What I would like it to output is:</p>
  
  <pre><code>{"field1":"Ma\u00EBl H\u00F6rz"}
  </code></pre>
  
  <p>How can I accomplish this?</p>