A wrapper class is the collection of various data types in Salesforce. Wrapper class in salesforce contains objects or collection of objects. Apex and Visualforce users find wrapper class extremely useful to solve major problems in salesforce. Wrapper class wraps data from different objects and presents them as a new object.
A salesforce object does not have a database or an API but is a valid object. Wrapper classes can hold multiple objects together. These contain multiple data types and are known as custom objects.
Salesforce has MVC architecture to implement multiple objects in wrapper classes successfully. A wrapper class is also known as a custom object as it can hold various data types and fields simultaneously.
Wrapper class helps in wrapping multiple objects from the databases. It is used in managing several business problems by the developer to customize salesforce applications.
Wrapper class is applied as an everyday tool in salesforce and is presented on the Visualforce platform for extra control over the data objects. Wrapper class adds more functionality to the salesforce platform to maximize user capabilities.
To understand the everyday patterns in wrapper class it is necessary to have a clear view of MVC architecture in Salesforce which helps developers build cloud based applications.
Salesforce MVC platform:-
MVC (Model view controller) is a Salesforce architecture, which helps to maintain different views of the same data. In MVC pattern the object is separated into three categories – Models( maintain data), View ( display entire or part of the data ) , controller ( for controlling events around the model and view ). The model manages data information by responding to requests by the view and changes the state of the data in response to requests by the controller.
Model also notifies the view on the changes of the data types in Salesforce for effective response. There can be multiple views on a single model. The view layer is made up of Visualforce pages . Each Visualforce page is linked with controllers in Salesforce and standard controllers can be written by using the Apex language. Model classes are also written in Apex, a language similar to Java.
There are several benefits of using the MVC architecture in wrapper classes:-
Reliability- An application layer can be changed by using the MVC code. Since the different layers are separate, it is easy to change the look of the application.
Low cost development- Programmers can maintain user interfaces within a minimum budget. Developer time is reduced, as controller control the interface actions and view helps in presenting the data to the users in a structured manner.
Easy maintenance – MVC architecture can be maintained independently and have reusable components.
Wrapper class in Apex can store different data types. Apex is the platform in which Salesforce developers can design applications based on the SAAS (Software as a Service ) platform. With the help of Apex, developers can get access to the Salesforce CRM database. An API interface assists developers to build different applications of the wrapper class within Salesforce.
A wrapper class example in Salesforce – A wrapper class can be used for accessing accounts displayed in the block table. A checkbox option is provided and the various records can be displayed in accordance with their serial numbers. This will result in creation of multiple objects by using the data wrapper to fulfill specific requirements and is an ideal wrapper class example.
A Map class in Salesforce is key value pairs, which can be of any data type like primitive type, Objects, user defined type, collections and built in Apex types. The map will give value based on the key and the value can be duplicated. Sometimes Apex map is sorted by using wrapper class, as map does not have any sorting functionalities.
The testing framework of the Apex helps to write high quality codes to meet requirements. Apex test class is in use for testing bugs in the codes to give a better output. Apex code coverage can be increased in wrapper class without any breaks in between.
There are several features, which denote how to cover wrapper class in test class:-
- The class is kept private and created as an original class.
- Test method keyword is used for static test class.
- The test data should be prepared before the test runs and actual testing codes should happen within fresh governor limits.
- Once the test code runs, the results should come out as expected.
- Multiple methods should be used in test cases for testing a simple trigger.
What is the use of wrapper classes ?
- Wrapper class is used as a data visualization technique by developers in JSON structure.
- It is easy to manage relationships between different objects while using wrapper class, as developers are not required to pass any MAP structure.
- sObjects can be passed and extended to the class constructors without any penalty.
- Wrapper class helps Salesforce developers organize the data effectively if the data is properly nested.
- A smaller view state of the data can be maintained if it is accessed through the browser.
- Container classes and wrapper classes, when maintained independently, prevents code duplication.
Advantages of wrapper class in java:-
- Wrapper class converts primitive data types in Java into object oriented data. A new field is created where primitive data types can be stored.
- Wrapper class gives a name to the primitive data value, which makes the interface more meaningful.
- Null values are allowed by wrapper class objects and not by primitive data types.
Wrapper class Salesforce is used by developers to create objects using Apex code. Wrapper class is a solution to numerous Salesforce problems because of its extended functionality. Data wrapping helps to create custom objects with specific properties to make the data user friendly.
Business organizations use wrapper class to perform various activities and solve numerous problems in the Salesforce instance. Developers use wrapper class as an everyday tool because of its wide range of benefits. Wrapper class consolidates several fields to provide extra flexibility over the data objects.