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Java

Upload File from String

See more Google Drive Examples

Uploads a text file where the contents of the file are contained in a string variable.

See Google Drive Files: create for more details.

Also See Google Drive Multipart Upload for more details.

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;

    success = true;

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

    // This example uses a previously obtained access token having permission for the 
    // Google Drive scope.

    CkAuthGoogle gAuth = new CkAuthGoogle();
    gAuth.put_AccessToken("GOOGLE-DRIVE-ACCESS-TOKEN");

    CkRest rest = new CkRest();

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

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

    // A multipart upload to Google Drive needs a multipart/related Content-Type
    rest.AddHeader("Content-Type","multipart/related");

    // Specify each part of the request.

    // The 1st part is JSON with information about the file.
    rest.put_PartSelector("1");
    rest.AddHeader("Content-Type","application/json; charset=UTF-8");

    CkJsonObject json = new CkJsonObject();
    json.AppendString("name","helloWorld.txt");
    json.AppendString("description","A simple text file that says Hello World.");
    json.AppendString("mimeType","text/plain");
    rest.SetMultipartBodyString(json.emit());

    // The 2nd part is the file content.
    // In this case, we'll upload a simple text file containing "Hello World!"
    rest.put_PartSelector("2");
    rest.AddHeader("Content-Type","text/plain");

    String fileContents = "Hello World!";
    rest.SetMultipartBodyString(fileContents);

    String jsonResponse = rest.fullRequestMultipart("POST","/upload/drive/v3/files?uploadType=multipart");
    if (rest.get_LastMethodSuccess() != 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 JSON: " + jsonResponse);
        return;
        }

    // Show the JSON response.
    json.Load(jsonResponse);

    // Show the full JSON response.
    json.put_EmitCompact(false);
    System.out.println(json.emit());

    // A successful response looks like this:
    // {
    //   "kind": "drive#file",
    //   "id": "0B53Q6OSTWYoldmJ0Z3ZqT2x5MFk",
    //   "name": "Untitled",
    //   "mimeType": "text/plain"
    // }

    // Get the fileId:
    System.out.println("fileId: " + json.stringOf("id"));
  }
}