Android™

Compute Glacier SHA256 Tree Hash of a File

See more Amazon Glacier Examples

Computes the Amazon Glacier SHA256 tree hash for a file.

Note: This example requires Chilkat v9.5.0.78 or greater.

Android™

// Important: Don't forget to include the call to System.loadLibrary
// as shown at the bottom of this code sample.
package com.test;

import android.app.Activity;
import com.chilkatsoft.*;

import android.widget.TextView;
import android.os.Bundle;

public class SimpleActivity extends Activity {

  private static final String TAG = "Chilkat";

  // Called when the activity is first created.
  @Override
  public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

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

    CkCrypt2 crypt = new CkCrypt2();

    // For more information about Amazon Glacier tree hashes, see Computing Glacier Checksums
    // Chilkat added the "sha256-tree-hash" algorithm in v9.5.0.78 to make it easy to compute the Glacier tree hash checksum
    // of a file or from bytes in memory.
    crypt.put_HashAlgorithm("sha256-tree-hash");

    // Return the hash in lowercase hexidecimal format.
    crypt.put_EncodingMode("hexlower");

    String treeHashHex = crypt.hashFileENC("qa_data/jpg/penguins.jpg");
    Log.i(TAG, "SHA256 tree hash = " + treeHashHex);

  }

  static {
      System.loadLibrary("chilkat");

      // Note: If the incorrect library name is passed to System.loadLibrary,
      // then you will see the following error message at application startup:
      //"The application <your-application-name> has stopped unexpectedly. Please try again."
  }
}