az-ak

// All the standard and custom objects in the Org
List<EntityDefinition> entityDefs = [select QualifiedApiName from EntityDefinition];

// Forming a list of Entity API names
List<String> entityNames = new List<String>();
for(EntityDefinition entityDef: entityDefs){
	if(!entityDef.QualifiedApiName.endsWith('kav')){
		entityNames.add(entityDef.QualifiedApiName);
	}
}

az-ak

global without sharing class SandboxPostCopyUpd implements SandboxPostCopy {
    global void runApexClass(SandboxContext context) {
        LIst<Contact> ConList = [SELECT ID FROM CONTACT];
        for (Contact con : ConList) {
            con.Email = 'dummy@example.com';
        }
        update ConList;
    }
}

az-ak

<apex:page docType="html-5.0" sidebar="false">
  <apex:stylesheet value="//maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css"/>
  <apex:includeScript value="//ajax.googleapis.com/ajax/libs/jquery/3.1.1/jquery.min.js"/>

  <script>
    jQuery(document).ready(function($) {
      $.ajax('/services/data/v38.0/limits',
        {
          beforeSend: function(xhr) {
            // Set the OAuth header from the session ID