(Java) Google Contacts - Retrieve as JSON

Demonstrates how to retrieve Google Contacts as JSON.

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import com.chilkatsoft.*;

public class ChilkatExample {

  static {
    try {
        System.loadLibrary("chilkat");
    } catch (UnsatisfiedLinkError e) {
      System.err.println("Native code library failed to load.\n" + e);
      System.exit(1);
    }
  }

  public static void main(String argv[])
  {
    // This example requires the Chilkat API to have been previously unlocked.
    // See Global Unlock Sample for sample code.

    // --------------------------------------------------------------------------------------------------------
    // Note: The code for setting up the Chilkat REST object and making the initial connection can be done once.
    // Once connected, the REST object may be re-used for many REST API calls.
    // (It's a good idea to put the connection setup code in a separate function/subroutine.)
    // --------------------------------------------------------------------------------------------------------

    // It is assumed we previously obtained an OAuth2 access token.
    // This example loads the JSON access token file 
    // saved by this example: Get Google Contacts OAuth2 Access Token

    CkJsonObject jsonToken = new CkJsonObject();
    boolean success = jsonToken.LoadFile("qa_data/tokens/googleContacts.json");
    if (success != true) {
        System.out.println("Failed to load googleContacts.json");
        return;
        }

    CkAuthGoogle gAuth = new CkAuthGoogle();
    gAuth.put_AccessToken(jsonToken.stringOf("access_token"));

    CkRest rest = new CkRest();

    // Connect using TLS.
    boolean bAutoReconnect = true;
    success = rest.Connect("www.google.com",443,true,bAutoReconnect);

    // Provide the authentication credentials (i.e. the access token)
    rest.SetAuthGoogle(gAuth);

    // ----------------------------------------------
    // OK, the REST connection setup is completed..
    // ----------------------------------------------

    // To retrieve the contacts, we need to send the following:

    // 	GET /m8/feeds/contacts/default/full
    // 	GData-Version: 3.0

    // To get the contacts data in JSON format, set the "alt" query parameter to "json"
    rest.AddQueryParam("alt","json");
    rest.AddHeader("GData-Version","3.0");

    CkStringBuilder sbResponseBody = new CkStringBuilder();
    success = rest.FullRequestNoBodySb("GET","/m8/feeds/contacts/default/full",sbResponseBody);
    if (success != true) {
        System.out.println(rest.lastErrorText());
        return;
        }

    // A successful response will have a status code equal to 200.
    if (rest.get_ResponseStatusCode() != 200) {
        System.out.println("response status code = " + rest.get_ResponseStatusCode());
        System.out.println("response status text = " + rest.responseStatusText());
        System.out.println("response header: " + rest.responseHeader());
        System.out.println("response body: " + sbResponseBody.getAsString());
        return;
        }

    // If the 200 response was received, then the contacts JSON is contained
    // in the response body.
    CkJsonObject json = new CkJsonObject();
    json.LoadSb(sbResponseBody);
    json.put_EmitCompact(false);

    // Save the pretty-printed JSON response to a file.
    sbResponseBody.Clear();
    json.EmitSb(sbResponseBody);
    sbResponseBody.WriteFile("qa_output/google_contacts.json","utf-8",false);

    // Parse the Google Contacts JSON, and iterate over the contacts..
    int totalResults = json.IntOf("feed.openSearch$totalResults.$t");
    int startIndex = json.IntOf("feed.openSearch$startIndex.$t");
    int itemsPerPage = json.IntOf("feed.openSearch$itemsPerPage.$t");
    System.out.println("totalResults = " + totalResults);
    System.out.println("startIndex = " + startIndex);
    System.out.println("itemsPerPage = " + itemsPerPage);

    int numEntries = json.SizeOfArray("feed.entry");
    int i = 0;
    while (i < numEntries) {
        json.put_I(i);
        System.out.println((i+1) + " ----");
        System.out.println("title: " + json.stringOf("feed.entry[i].title.$t"));

        String fullName = json.stringOf("feed.entry[i].gd$name.gd$fullName.$t");
        if (json.get_LastMethodSuccess() == true) {
            System.out.println("fullName: " + fullName);
            }

        // There can be multiple email addresses, so it's stored as a JSON array..
        int numEmailAddresses = json.SizeOfArray("feed.entry[i].gd$email");
        int j = 0;
        while (j < numEmailAddresses) {
            String emailAddress = json.stringOf("feed.entry[i].gd$email[j].address");
            if (json.get_LastMethodSuccess() == true) {
                System.out.println("email address: " + emailAddress);
                }

            j = j+1;
            }

        i = i+1;
        }

    // A sample Google Contacts JSON response:

    // 	{ 
    // 	  "version": "1.0",
    // 	  "encoding": "UTF-8",
    // 	  "feed": { 
    // 	    "xmlns": "http://www.w3.org/2005/Atom",
    // 	    "xmlns$openSearch": "http://a9.com/-/spec/opensearch/1.1/",
    // 	    "xmlns$gContact": "http://schemas.google.com/contact/2008",
    // 	    "xmlns$batch": "http://schemas.google.com/gdata/batch",
    // 	    "xmlns$gd": "http://schemas.google.com/g/2005",
    // 	    "gd$etag": "\"QHw5eTVSLyt7I2A9XRFaE0kNTwI.\"",
    // 	    "id": { 
    // 	      "$t": "chilkat.support@gmail.com"
    // 	    },
    // 	    "updated": { 
    // 	      "$t": "2016-11-17T01:57:41.221Z"
    // 	    },
    // 	    "category": [
    // 	      { 
    // 	        "scheme": "http://schemas.google.com/g/2005#kind",
    // 	        "term": "http://schemas.google.com/contact/2008#contact"
    // 	      }
    // 	    ],
    // 	    "title": { 
    // 	      "$t": "Chilkat Support's Contacts"
    // 	    },
    // 	    "link": [
    // 	      { 
    // 	        "rel": "alternate",
    // 	        "type": "text/html",
    // 	        "href": "https://www.googleapis.com/"
    // 	      },
    // 	      { 
    // 	        "rel": "http://schemas.google.com/g/2005#feed",
    // 	        "type": "application/atom+xml",
    // 	        "href": "https://www.googleapis.com/m8/feeds/contacts/chilkat.support%40gmail.com/full"
    // 	      },
    // 	      { 
    // 	        "rel": "http://schemas.google.com/g/2005#post",
    // 	        "type": "application/atom+xml",
    // 	        "href": "https://www.googleapis.com/m8/feeds/contacts/chilkat.support%40gmail.com/full"
    // 	      },
    // 	      { 
    // 	        "rel": "http://schemas.google.com/g/2005#batch",
    // 	        "type": "application/atom+xml",
    // 	        "href": "https://www.googleapis.com/m8/feeds/contacts/chilkat.support%40gmail.com/full/batch"
    // 	      },
    // 	      { 
    // 	        "rel": "self",
    // 	        "type": "application/atom+xml",
    // 	        "href": "https://www.googleapis.com/m8/feeds/contacts/chilkat.support%40gmail.com/full?max-results=25&alt=json"
    // 	      },
    // 	      { 
    // 	        "rel": "next",
    // 	        "type": "application/atom+xml",
    // 	        "href": "https://www.googleapis.com/m8/feeds/contacts/chilkat.support%40gmail.com/full?max-results=25&alt=json&start-index=26"
    // 	      }
    // 	    ],
    // 	    "author": [
    // 	      { 
    // 	        "name": { 
    // 	          "$t": "Chilkat Support"
    // 	        },
    // 	        "email": { 
    // 	          "$t": "chilkat.support@gmail.com"
    // 	        }
    // 	      }
    // 	    ],
    // 	    "generator": { 
    // 	      "version": "1.0",
    // 	      "uri": "http://www.google.com/m8/feeds",
    // 	      "$t": "Contacts"
    // 	    },
    // 	    "openSearch$totalResults": { 
    // 	      "$t": "350"
    // 	    },
    // 	    "openSearch$startIndex": { 
    // 	      "$t": "1"
    // 	    },
    // 	    "openSearch$itemsPerPage": { 
    // 	      "$t": "25"
    // 	    },
    // 	    "entry": [
    // 	      { 
    // 	        "id": { 
    // 	          "$t": "http://www.google.com/m8/feeds/contacts/chilkat.support%40gmail.com/base/0"
    // 	        },
    // 	        "gd$etag": "\"SX8zcTVSLyt7I2A9WxBXFU4MQwI.\"",
    // 	        "updated": { 
    // 	          "$t": "2010-01-26T20:07:48.189Z"
    // 	        },
    // 	        "app$edited": { 
    // 	          "xmlns$app": "http://www.w3.org/2007/app",
    // 	          "$t": "2010-01-26T20:07:48.189Z"
    // 	        },
    // 	        "category": [
    // 	          { 
    // 	            "scheme": "http://schemas.google.com/g/2005#kind",
    // 	            "term": "http://schemas.google.com/contact/2008#contact"
    // 	          }
    // 	        ],
    // 	        "title": { 
    // 	          "$t": "Joe Sample"
    // 	        },
    // 	        "link": [
    // 	          { 
    // 	            "rel": "http://schemas.google.com/contacts/2008/rel#photo",
    // 	            "type": "image/*",
    // 	            "href": "https://www.googleapis.com/m8/feeds/photos/media/chilkat.support%40gmail.com/0"
    // 	          },
    // 	          { 
    // 	            "rel": "self",
    // 	            "type": "application/atom+xml",
    // 	            "href": "https://www.googleapis.com/m8/feeds/contacts/chilkat.support%40gmail.com/full/0"
    // 	          },
    // 	          { 
    // 	            "rel": "edit",
    // 	            "type": "application/atom+xml",
    // 	            "href": "https://www.googleapis.com/m8/feeds/contacts/chilkat.support%40gmail.com/full/0"
    // 	          }
    // 	        ],
    // 	        "gd$name": { 
    // 	          "gd$fullName": { 
    // 	            "$t": "Joe Sample"
    // 	          },
    // 	          "gd$givenName": { 
    // 	            "$t": "Joe"
    // 	          },
    // 	          "gd$familyName": { 
    // 	            "$t": "Sample"
    // 	          }
    // 	        },
    // 	        "gd$email": [
    // 	          { 
    // 	            "address": "somebody@gmail.com",
    // 	            "primary": "true",
    // 	            "rel": "http://schemas.google.com/g/2005#other"
    // 	          }
    // 	        ]
    // 	      },
    // 		... more entries ...
    // 	
  }
}