title: Dgraph in Java. How to run raw string mutation query?
body: <p>I need do be able to run raw string mutation queries without using of newBuilder():</p>
  
  <pre><code>Gson gson = new Gson();
  String json = gson.toJson(newEmployer);
  Transaction newTransaction = this.dgraphClient.newTransaction();
  Mutation mu = Mutation.newBuilder().setSetJson(ByteString.copyFromUtf8(json.toString())).build();
  newTransaction.mutate(mu);
  </code></pre>
  
  <p>I want to run:</p>
  
  <pre><code>String email = "ba@a.aa";
  String userType = "JOB_SEEKER";
  Transaction newTransaction = this.dgraphClient.newTransaction();
  String query = 
          "{\n" +
          "    set { \n" +
          "       _:user &lt;label&gt; \"USER\" . \n" +
          "      _:user &lt;userType&gt; \"" + email + "\" . \n" +
          "      _:user &lt;email&gt; \"" + userType + "\" . \n" +
          "    }\n" +
          "}";
  Mutation mu = Mutation.parseFrom(ByteString.copyFromUtf8(query));
  newTransaction.mutate(mu);
  </code></pre>
  
  <p>But I get the error on run-time: "While parsing a protocol message, the input ended unexpectedly in the middle of a field.  This could mean either that the input has been truncated or that an embedded message misreported its own length."</p>