Sample code for 30+ languages & platforms
Java

Get a List of Message IDs in GMail User's Mailbox

See more GMail REST API Examples

Demonstrates how to get a list of message IDs in a GMail mailbox. The "userId" can be either the user's email address or the special value "me" to indicate the authenticated user.

Chilkat Java Downloads

Java
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[])
  {
    boolean success = false;

    // This example requires the Chilkat API to have been previously unlocked.
    // See Global Unlock Sample for sample code.

    CkHttp http = new CkHttp();

    http.put_AuthToken("ACCESS_TOKEN");

    http.put_Accept("application/json");

    CkHttpResponse resp = new CkHttpResponse();
    success = http.HttpNoBody("GET","https://www.googleapis.com/gmail/v1/users/userId/messages",resp);
    if (success == false) {
        System.out.println(http.lastErrorText());
        return;
        }

    System.out.println("Response Status Code: " + resp.get_StatusCode());

    CkJsonObject jsonResponse = new CkJsonObject();
    jsonResponse.Load(resp.bodyStr());
    jsonResponse.put_EmitCompact(false);
    System.out.println(jsonResponse.emit());

    if (resp.get_StatusCode() != 200) {
        System.out.println("Failed.");
        return;
        }

    // {
    //   "messages": [
    //     users.messages Resource
    //   ],
    //   "nextPageToken": string,
    //   "resultSizeEstimate": unsigned integer
    // }

    String id;
    String threadId;

    int resultSizeEstimate = jsonResponse.IntOf("resultSizeEstimate");
    int i = 0;
    int count_i = jsonResponse.SizeOfArray("messages");
    while (i < count_i) {
        jsonResponse.put_I(i);
        id = jsonResponse.stringOf("messages[i].id");
        threadId = jsonResponse.stringOf("messages[i].threadId");
        i = i+1;
        }
  }
}