My version of "Select All Mimic2 in SOQL

Mimic SQL select * statement in SOQL using Apex

global with sharing class CommonClass {

  global  List<Object> selectAllFromTable(String objectName, String whereCondition, String order, String limit1){
    String query = selectAllQuery(objectName, whereCondition);
    query += ' ORDER BY '+order+' LIMIT '+limit1;
    try {
            return database.query(query);
    } catch (QueryException e){
            //perform exception handling
            System.debug('failed to selectAllFromTable');
            System.debug('query: '+query+', tableName: '+objectName);
            return NULL;
    }
  }

  global  List<Object> selectAllFromTable(String objectName, String whereCondition, String order){
    String query = selectAllQuery(objectName, whereCondition);
    query += ' ORDER BY '+order;
    try {
            return database.query(query);
    } catch (QueryException e){
            //perform exception handling
            System.debug('failed to selectAllFromTable');
            System.debug('query: '+query+', tableName: '+objectName);
            return NULL;
    }
  }

  global  List<Object> selectAllFromTable(String objectName, String whereCondition){
    
    String query = selectAllQuery(objectName, whereCondition);
    try {
            return database.query(query);
    } catch (QueryException e){
            //perform exception handling
            System.debug('failed to selectAllFromTable');
            System.debug('query: '+query+', tableName: '+objectName);
            return NULL;
    }
  }

  private  String selectAllQuery(String objectName, String whereCondition){
    /*
    * @description: A code snippet that mimics the popular Select * SQL syntax in force.com's Apex language.
    */

    // Initialize setup variables
    String query = 'SELECT';
    Map<String, Schema.SObjectField> objectFields = Schema.getGlobalDescribe().get(objectName).getDescribe().fields.getMap();

    // Grab the fields from the describe method and append them to the queryString one by one.
    for(String s : objectFields.keySet()) {
       query += ' ' + s + ', ';
    }

    // Strip off the last comma if it exists.
    if (query.subString(query.Length()-1,query.Length()) == ','){
        query = query.subString(0,query.Length()-1);
    }

    // Add FROM statement
    query += ' FROM ' + objectName;

    // Add on a WHERE/ORDER/LIMIT statement as needed
    query += ' WHERE '+whereCondition; // modify as needed
    return query;
  }

}