global class EmailAcknowledgementBatch implements Database.Batchable<sObject>{

public set<ID> emailId = new set<Id>();
global Database.querylocator start(Database.BatchableContext BC){
            return Database.getQueryLocator([select id,Name,Email,Date__c,CreatedDate from Contact where CreatedDate >=:system.today()]);}

global void execute(Database.BatchableContext BC, List<sObject> scope){
    List<Contact> conList = new List<Contact>();
    List<Messaging.Email> messages = new List<Messaging.Email>();
    
   for(sObject s : scope){
       Contact a = (Contact)s;
        if(a.Email != Null){
           // email = a.Email;
            emailId.add(a.Id);
            Messaging.SingleEmailMessage message = new Messaging.SingleEmailMessage();
             message.setTargetObjectId(a.Id );
        //message.setWhatId( a.Id );
                 message.setSenderDisplayName('Batch Example');
     // message.setPlainTextBody('Batch Process has completed');
        message.setSubject('Acknowledgement !!!'); // //
        message.setPlainTextBody('Dear ' + a.Name + 'Your Profile is created with'+a.Email +'Email');
        messages.add( message );   
            }
        }
     
    // Send all the e-mails.
    Messaging.SendEmailResult[] results = Messaging.sendEmail( messages );
//update conList;

    
}
global void finish(Database.BatchableContext BC){
  //List<Contact> con = [select id,Email,Date__c,CreatedDate,Name from Contact where CreatedDate <=:system.today() ];
    //Messaging.MassEmailMessage mail = new Messaging.MassEmailMessage();
    
    //mail.setTargetObjectIds(emailId);
    //system.debug('----email--->>>' + email);
    //mail.setSenderDisplayName('Batch Example');
     // mail.setPlainTextBody('Batch Process has completed');
    //mail.setSubject('Acknowledgement !!!'); // //subject
    //mail.setPlainTextBody('Dear ' + con[0].Name + 'Your Profile is created with'+con[0].Email +'Email Id');

//Messaging.sendEmail(new Messaging.MassEmailMessage[] { mail });
}
}