Creating a static factory method using @AllArgsConstructor
If we would like to create instance using a static factory method, staticName attribute of @AllArgsConstructor allows us to generates a private all-args constructors and an additional static factory method that wraps around the private constructor is generated.
What is Java AllArgsConstructor?
@AllArgsConstructor annotation automatically generates a constructor with a parameter for each field in your class . ... i.e for the case of final fields already initialized with a value.
What is @AllArgsConstructor?
@AllArgsConstructor generates a constructor with 1 parameter for each field in your class . ... Each of these annotations allows an alternate form, where the generated constructor is always private, and an additional static factory method that wraps around the private constructor is generated.
When would you use args constructor?
- @AllArgsConstructor generates a constructor requiring argument for every field in the annotated class.
- @NoArgsConstructor generates a constructor with no parameter.
What is the use of Lombok?
Project Lombok is a java library tool that is used to minimize/remove the boilerplate code and save the precious time of developers during development by just using some annotations. In addition to it, it also increases the readability of the source code and saves space.
Can we use AllArgsConstructor and NoArgsConstructor?
@NoArgsConstructor will generate a constructor with no parameters . ... The order of the parameters match the order in which the fields appear in your class. @AllArgsConstructor generates a constructor with 1 parameter for each field in your class. Fields marked with @NonNull result in null checks on those parameters.
Why do we need NoArgsConstructor?
@NoArgsConstructor(staticName = “getInstance”) generates a static factory method named with getInstance, staticName attribute of @NoArgsConstructor allows us to generates a private no-args constructors and an additional static factory method that wraps around the private constructor is generated .
What is no args constructor?
No-argument constructor: A constructor that has no parameter is known as the default constructor . ... And if we write a constructor with arguments or no-arguments then the compiler does not create a default constructor. Default constructor provides the default values to the object like 0, null, etc.
How does required args constructor work?
Generates a constructor with required arguments . Required arguments are uninitialized final fields and fields with constraints such as @NonNull . Default access modifier is public .
What is SuperBuilder?
@SuperBuilder generates a protected constructor on the class that takes a builder instance as a parameter . ... You can use @SuperBuilder(toBuilder = true) to also generate an instance method in your class called toBuilder() ; it creates a new builder that starts out with all the values of this instance.
What happens if you keep return type for a constructor?
If we add a return type to a constructor, then it will become a method of the class . This is the way java runtime distinguish between a normal method and a constructor. ... It’s recommended to not have method name same as the class name because it creates confusion.
What is @JsonIgnoreProperties?
@JsonIgnoreProperties is used at class level to mark a property or list of properties to be ignored .
What is a constructor in Java?
A constructor in Java is a block of code similar to a method that’s called when an instance of an object is created . ... Unlike methods, constructors are not considered members of a class. A constructor is called automatically when a new instance of an object is created.
Is Lombok good or bad?
Using lombok may be a good idea but you must be aware that upgrading your compiler may break your code. The probability is low but I always feel uncomfortable using non-public APIs. Very good point. History of Java 8 + Lombok showed us that this can be a problem.
Should we use Lombok or not?
Lombok is a very popular library in the Java world that aims to help you write less repetitive code. Many people who are opposed to the use of this tool say that if you use a good text editor, you can take advantage of autocompletes and then you won’t need Lombok .
Is Lombok a good practice?
Lombok is an awesome Java library. It helps to reduce the amount of ‘infrastructural code’. You don’t need to write constructors, getters, setters, and even builders anymore. All you have to do is to put the proper annotations and the plugin will generate everything for you.
