(Chilkat for Android™ API)
Extract a File from a .p7m (PKCS7 Signed-Data)

Android™ example to extract the original file from a .p7m (Signed-Data PKCS7 Format) The .p7m contains the signed contents of the original file. It can be verified and restored by calling VerifyP7M.

Download: Chilkat for Android™ Java Libraries

// 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 {
  // Called when the activity is first created.
  @Override
  public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    TextView tv = new TextView(this);
    String outStr = "";

    CkCrypt2 crypt = new CkCrypt2();

    //  Any string argument automatically begins the 30-day trial.
    boolean success;
    success = crypt.UnlockComponent("30-day trial");
    if (success != true) {
        outStr += crypt.lastErrorText() + "\n";
        tv.setText(outStr);
        setContentView(tv);
        return;
    }

    String outFile;
    outFile = "/Users/chilkat/testData/pdf/sample.pdf";
    String inFile;
    inFile = "/Users/chilkat/testData/p7m/sample.pdf.p7m";

    //  Verify and restore the original file:
    success = crypt.VerifyP7M(inFile,outFile);
    if (success == false) {
        outStr += crypt.lastErrorText() + "\n";
        tv.setText(outStr);
        setContentView(tv);
        return;
    }

    outStr += "Success!" + "\n";
    tv.setText(outStr);
    setContentView(tv);
  }

  static {
      // Important: Make sure the name passed to loadLibrary matches the shared library
      // found in your project's libs/armeabi directory.
      //  for "libchilkat.so", pass "chilkat" to loadLibrary
      //  for "libchilkatemail.so", pass "chilkatemail" to loadLibrary
      //  etc.
      // 
      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."
  }
}