title: How to add value of key to another in Hash Map if there are any duplicate keys
body: <p>i am trying to put json data into HashMap which may contain lot of duplicate keys. 
  For example:</p>
  
  <pre><code>    {
      "member Detial": {
          "firstname": "jhon",
          "lastName": "wick",
          "Address": "New York",
          "Email": "jhonwick@boogiman.com",
          "Fax Number": "09876543",
          "Contact Number": "9876543210",
          "Password": "newyorkcitizen",
          "confirm password": "newyorkcitizen",
          "NationalProviderIdentifier": "Apollo",
          "PartyID": "1"
      },
  
  
      "Physician": {
          "firstname": "jhon",
          "lastName": "wick",
          "Email": "jhonwick@boogiman.com",
          "Fax Number": "09876543",
          "Contact Number": "9876543210",
          "NationalProviderIdentifier": "Apollo",
          "PartyID": "1"
  
      },
  
      "PhysicianGroup": {
          "Address": "New York",
          "Email": "jhonwick@boogiman.com",
          "Fax Number": "09876543",
          "Contact Number": "9876543210",
          "NationalProviderIdentifier": "Apollo",
          "Hospital name": "Apollo",
          "Tax ID": "12345",
          "PartyID": "1"
  
      },
              "Physician": {
          "Address": "New York",
          "Email": "jhonwick@boogiman.com",
          "Fax Number": "09876543",
          "Contact Number": "9876543210",
          "NationalProviderIdentifier": "Apollo",
          "Hospital name": "Apollo",
          "Tax ID": "12345",
          "PartyID": "1"
  
      },
  }
  </code></pre>
  
  <p>in the above json file "member details" is considered as key and data within brackets is considered as value. but problem here is there can be duplicate keys like "Physician" in above json example.</p>
  
  <p>i want to add value of second "physician" to first "Physician" without overriding its value and delete the duplicate key. 
  for example:`</p>
  
  <pre><code>   {
  
  "member Detial": {
      "firstname": "jhon",
      "lastName": "wick",
      "Address": "New York",
      "Email": "jhonwick@boogiman.com",
      "Fax Number": "09876543",
      "Contact Number": "9876543210",
      "Password": "newyorkcitizen",
      "confirm password": "newyorkcitizen",
      "NationalProviderIdentifier": "Apollo",
      "PartyID": "1"
  },
  
  
  "Physician": [{
          "firstname": "jhon",
          "lastName": "wick",
          "Email": "jhonwick@boogiman.com",
          "Fax Number": "09876543",
          "Contact Number": "9876543210",
          "NationalProviderIdentifier": "Apollo",
          "PartyID": "1"
      },
      {
          "Address": "New York",
          "Email": "jhonwick@boogiman.com",
          "Fax Number": "09876543",
          "Contact Number": "9876543210",
          "NationalProviderIdentifier": "Apollo",
          "Hospital name": "Apollo",
          "Tax ID": "12345",
          "PartyID": "1"
      }
  ],
  "PhycianGroup": {
      "Address": "New York",
      "Email": "jhonwick@boogiman.com",
      "Fax Number": "09876543",
      "Contact Number": "9876543210",
      "NationalProviderIdentifier": "Apollo",
      "Hospital name": "Apollo",
      "Tax ID": "12345",
      "PartyID": "1"
  
    }
  }
  </code></pre>
  
  <p>`</p>