Table of contents


Introduction to Supplier functional interface

Supplier is a functional interface that is used to generate data.

Below is its definition on Java docs.

@FunctionalInterface
public interface Supplier<T> {
    T get();
}

For example:

Supplier<Integer> intRand = () -> {
    Random rand = new Random();
    return rand.nextInt(140);
};


When to use

  • When our methods or functions do not need input, but it expected output.


Some specializations of Suppliers interface

Belows are some specializations of Supplier:

@FunctionalInterface
public interface BooleanSupplier<T> {
    boolean getAsBoolean();
}

@FunctionalInterface
public interface IntSupplier<T> {
    int getAsInt();
}

@FunctionalInterface
public interface LongSupplier<T> {
    long getAsLong();
}

@FunctionalInterface
public interface DoubleSupplier<T> {
    double getAsDouble();
}


Wrapping up


Refer:

Functional Interfaces in Java ebook