soverby

package com.soverby.test;

import org.junit.Test;
import java.util.Optional;
import java.util.function.Function;

import static org.assertj.core.api.Java6Assertions.assertThat;

public class NullableChain {

soverby

package com.accolade.test;

import java.util.UUID;

public class TestUUID {

    public static void main(String[] args) {
        // Valid UUID
        UUID uuid1 = UUID.fromString("123e4567-e89b-12d3-a456-426655440000");
        // Not a valid UUID, UUID will left pad zeros

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import lombok.Data;

import java.util.HashMap;
import java.util.Map;
import java.util.function.Consumer;
import java.util.function.Supplier;

public class ConsumerSupplierExample {

    public static void main(String[] args) {

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import java.util.ArrayList;
import java.util.List;
import java.util.function.Function;
import java.util.function.Supplier;

public class FormingClosure {

    Supplier<List<String>> supplier;

    public static void main(String[] args) {

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import java.util.Date;
import java.util.Optional;

public class FunctionWithCheckedException {

    @FunctionalInterface
    public interface SomeAppropriateSemantic<T, R> {
        public R semantic(T t) throws CustomException;
    };

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import java.util.Date;
import java.util.function.Function;

public class MultiParameterFunction {

    // Bad
    @FunctionalInterface
    public interface TriFunction<T, U, V, R> {
        public R customMethod(T t, U u, V v);
    }

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import java.util.function.BiFunction;
import java.util.function.Consumer;
import java.util.function.Supplier;

public class JavaLambdaSyntax {

    private Consumer<String> stringConsumer;
    private Supplier<String> stringSupplier;
    private BiFunction<String, String, String> stringBiFunction;

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public class OptionalChainingComposed {

    public static void main(String[] args) {
        OptionalChainingComposed optionalChaining = new OptionalChainingComposed();
        optionalChaining.happyPath();
        optionalChaining.nullInput();
    }

    public void happyPath() {
        nonNullPipeline("happyPath")

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public class OptionalChaining {
    public static void main(String[] args) {
        OptionalChaining optionalChaining = new OptionalChaining();
        optionalChaining.happyPath();
        optionalChaining.nullInput();
        optionalChaining.thereBeNullsHereOne();
        optionalChaining.thereBeNullsHereTwo();
    }

    // Happy path with a pipeline that doesn't return nulls

soverby

// And finally a functional example of the find location with non-zero inventory for item example
public class Functional {
  
    // @Inject
    private ItemRepository itemRepository;
    // @Inject
    private InventoryLocationRepostitory inventoryLocationRepostitory;

    // Monadic approach, composed behaviors
    // "The monad represents computations with a sequential structure: a monad defines what it means to chain operations together."