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Java

Get a Google Drive Access Token using a JSON Private Key

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Demonstrates how to get a Google Drive API access token using a JSON service account private key.

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Chilkat2 Java
import com.chilkatsoft.chilkat2.AuthGoogle;
import com.chilkatsoft.chilkat2.ChilkatException;
import com.chilkatsoft.chilkat2.FileAccess;
import com.chilkatsoft.chilkat2.Socket;

public class ChilkatExample {

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

        // First load the JSON key into a string.
        FileAccess fac = new FileAccess();
        String jsonKey;
        try {
            jsonKey = fac.readEntireTextFile("qa_data/googleApi/chilkatcloud-b8826e030499.json", "utf-8");
        } catch (ChilkatException e) {
            System.out.println(e.getLastErrorText());
            return;
        }

        AuthGoogle gAuth = new AuthGoogle();
        gAuth.setJsonKey(jsonKey);

        // Choose a scope.
        gAuth.setScope("https://www.googleapis.com/auth/drive");

        // Request an access token that is valid for this many seconds.
        gAuth.setExpireNumSeconds(3600);

        // If the application is requesting delegated access:
        // The email address of the user for which the application is requesting delegated access,
        // then set the email address here. (Otherwise leave it empty.)
        gAuth.setSubEmailAddress("");

        // Connect to www.googleapis.com using TLS (TLS 1.2 is the default.)
        // The Chilkat socket object is used so that the connection can be established
        // through proxies or an SSH tunnel if desired.
        Socket tlsSock = new Socket();
        try {
            tlsSock.connect("www.googleapis.com", 443, true, 5000);

            // Send the request to obtain the access token.
            gAuth.obtainAccessToken(tlsSock);
        } catch (ChilkatException e) {
            System.out.println(e.getLastErrorText());
            return;
        }

        // Examine the access token:
        System.out.println("Access Token: " + gAuth.getAccessToken());
    }
}