Error building with custom java code [Solved]

I’m doing a game that needs to access the calendar in the mobile and save an event, i’ve build a java code and created a .jar file using Dr. Java:

package com.company.productname;

import com.unity3d.player.UnityPlayer;
import com.unity3d.player.UnityPlayerActivity;

import java.util.Calendar;
import android.os.Bundle;

import android.app.PendingIntent;
import android.content.Intent;
import android.content.Context;

import android.util.Log;
import android.os.Handler;

public class CalendarDate  {
   public void addEvent(Context ctx, String title) {
    //Log.d(TAG, "AddUsingIntent.addEvent()");
    Intent intent = new Intent(Intent.ACTION_EDIT);
    intent.setType("vnd.android.cursor.item/event");
    intent.putExtra("title", title);
    //intent.putExtra("beginTime", start.getTimeInMillis());
    //intent.putExtra("endTime", end.getTimeInMillis());
    intent.putExtra("allDay", true);
    ctx.startActivity(intent);
}
}

and i’ve added to the mannifest:

  <service android:name="es.astronauts.opengl.CalendarDate" />

to be able to access from a C# code, the code is:

#if UNITY_ANDROID
	private AndroidJavaObject playerActivityContext;
	#endif
	// Use this for initialization
	void Start () {
		inicio = 2015914730;
		fin = 2015914830;
		#if UNITY_ANDROID && !UNITY_EDITOR
		// Obtain unity context
		if(playerActivityContext == null) {
			AndroidJavaClass actClass = new AndroidJavaClass("com.unity3d.player.UnityPlayer");
			playerActivityContext = actClass.GetStatic<AndroidJavaObject>("currentActivity");
		}
		AndroidJavaClass jc = new AndroidJavaClass(packageName + ".CalendarDate");
		jc.CallStatic("addEvent", playerActivityContext,Title);
		#endif

	
	}

but when i build i get the next error:

can anyone help me?
Thank you so much!!

In order to solve this issue i’ve created a new folder called libs (with ans s) inside the assets folder, and drooped there the java clases