JarCastingFunBaseTools core library for Java
FunBaseTools Core Lib provides a functional and multipurpose library for Java developers.
How to install it
- Using maven:
<dependency>
<groupId>com.funbasetools</groupId>
<artifactId>fbt-core-java</artifactId>
<version>latest</version>
</dependency>
- You also can download the latest sources from the release badge above.
Features
The library has a set of useful features to apply functional programming to Java projects. Below you can see some utilities:
Lazy Evaluation
import com.funbasetools.Lazy;
class MyClass {
// This field value will be computed only when used the first time
private final Lazy<String> lazyField = Lazy.of(() -> {
// Perform a very complicated and big computation
return "This result will be computed only the first time";
});
public String getResult() {
return lazyField.get();
}
}
Streams
import com.funbasetools.collections.Stream;
import com.funbasetools.collections.Streams;
class MyClass {
// natural numbers stream
private final Stream<Integer> naturals = Streams.from(1);
// factorial stream
private final Stream<Integer> factorial = getFactorial();
// fibonacci stream
private final Stream<Integer> fibonacci = getFibonacci();
public void testNaturals() {
final Stream<Integer> evens = naturals.filter(i -> i % 2 == 0);
final Stream<Integer> odds = naturals.filter(i -> i % 2 != 0);
assert evens.corresponds(Streams.of(2, 4, 6, 8, 10, 12, 14, 16, 18, 20));
assert odds.corresponds(Streams.of(1, 3, 5, 7, 9, 11, 13, 15, 17, 19));
}
public void testFactorial() {
assert factorial
.corresponds(Streams.of(1, 2, 6, 24, 120, 720, 5040, 40320, 362880));
}
public void testFibonacci() {
assert factorialStream
.corresponds(Streams.of(1, 1, 2, 3, 5, 8, 13, 21, 34));
}
// private methods
/**
/* Creates a stream of pairs with the current fibonacci value and the next natural number,
/* after multiplying the pair, the result is the next factorial value.
/* Awesome!!!
*/
private Stream<Integer> getFactorial() {
return Streams
.ofNullable(1, () -> factorialStream
.zip(naturalStream.getTail())
.map(pair -> pair.getRight() * pair.getLeft())
);
}
/**
/* Creates a stream of pairs with the current and next fibonacci values and then adds the pair values.
/* The result is the next fibonacci number.
/* Wonderful right?
*/
private Stream<Integer> getFibonacci() {
return Streams
.ofNullable(1, 1)
.append(() -> fibonacci
.zip(fibonacci.getTail())
.map(pair -> pair.getLeft() + pair.getRight())
);
}
}
And more...
Also, you can find:
- Try, Success and Failures monads
- Function, Supply and Consumer extended types and their throwing exception similar
- Codecs
- Basic security API
Take a look to the unit tests of the library for more use cases and examples.
