title: How to convert google.protobuf.Struct field in java.util.Map<String, Object>?
body: <p>I have a message defined quotation_item.proto file which has google.protobuf.Struct field to parse metadata JSON.</p>
  
  <pre><code>message QuotationItemEntry {
      // Other fields
      google.protobuf.Struct metadata = 15;
  }
  </code></pre>
  
  <p>Also metadata field is defined in Java entity class</p>
  
  <pre><code>public class QuotationItem {
      // Other entity fields
      private Map&lt;String, Object&gt; metadata;
  }
  </code></pre>
  
  <p>I want to store the QuotationItemEntry object passed in gRPC request using spring boot application but not able to convert <code>google.protobuf.Struct</code> field in <code>java.util.Map&lt;String, Object&gt;</code>.</p>