OptionalInts.java
// Generated by delombok at Mon Nov 18 07:27:48 UTC 2024
package de.larssh.utils;
import java.util.Arrays;
import java.util.Optional;
import java.util.OptionalDouble;
import java.util.OptionalInt;
import java.util.OptionalLong;
import java.util.function.IntFunction;
import java.util.function.IntPredicate;
import java.util.function.IntToDoubleFunction;
import java.util.function.IntToLongFunction;
import java.util.stream.IntStream;
import de.larssh.utils.function.IntToIntFunction;
import edu.umd.cs.findbugs.annotations.Nullable;
/**
* This class contains helper methods for {@link OptionalInt}.
*/
public final class OptionalInts {
/**
* Predicate returning {@code true} for all values less than zero.
*/
public static final IntPredicate IS_NEGATIVE = value -> value < 0;
/**
* Predicate returning {@code true} for all values less than or equal to zero.
*/
public static final IntPredicate IS_NEGATIVE_OR_ZERO = value -> value <= 0;
/**
* Predicate returning {@code true} for all values greater than zero.
*/
public static final IntPredicate IS_POSITIVE = value -> value > 0;
/**
* Predicate returning {@code true} for all values greater than or equal to
* zero.
*/
public static final IntPredicate IS_POSITIVE_OR_ZERO = value -> value >= 0;
/**
* Returns a {@link Optional} consisting of the elements of {@code optional},
* boxed to an {@link Integer}.
*
* @param optional optional value
* @return a {@link Optional} consistent of the elements of {@code optional},
* boxed to an {@link Integer}
*/
public static Optional<Integer> boxed(final OptionalInt optional) {
return optional.isPresent() ? Optional.ofNullable(optional.getAsInt()) : Optional.empty();
}
/**
* If a value is present, and the value matches the given predicate, return an
* {@link OptionalInt} describing the value, otherwise return an empty
* {@link OptionalInt}.
*
* @param optional optional value
* @param predicate a predicate to apply to the value, if present
* @return an {@link OptionalInt} describing the value of {@code optional} if a
* value is present and the value matches the given predicate, otherwise
* an empty {@link OptionalInt}
*/
public static OptionalInt filter(final OptionalInt optional, final IntPredicate predicate) {
return optional.isPresent() && predicate.test(optional.getAsInt()) ? optional : OptionalInt.empty();
}
/**
* If a value is present, apply the provided {@link OptionalInt}-bearing mapping
* function to it, return that result, otherwise return an empty
* {@link OptionalInt}. This method is similar to
* {@link #map(OptionalInt, IntToIntFunction)}, but the provided mapper is one
* whose result is already an {@code OptionalInt}, and if invoked,
* {@code flatMap} does not wrap it with an additional {@link OptionalInt}.
*
* @param optional optional value
* @param mapper a mapping function to apply to the value, if present the
* mapping function
* @return the result of applying an {@link OptionalInt}-bearing mapping
* function to the value of this {@link OptionalInt}, if a value is
* present, otherwise an empty {@link OptionalInt}
*/
public static OptionalInt flatMap(final OptionalInt optional, final IntFunction<OptionalInt> mapper) {
return optional.isPresent() ? mapper.apply(optional.getAsInt()) : OptionalInt.empty();
}
/**
* If a value is present, apply the provided {@link OptionalDouble}-bearing
* mapping function to it, return that result, otherwise return an empty
* {@link OptionalDouble}. This method is similar to
* {@link #mapToDouble(OptionalInt, IntToDoubleFunction)}, but the provided
* mapper is one whose result is already an {@code OptionalDouble}, and if
* invoked, {@code flatMapToDouble} does not wrap it with an additional
* {@link OptionalDouble}.
*
* @param optional optional value
* @param mapper a mapping function to apply to the value, if present the
* mapping function
* @return the result of applying an {@link OptionalDouble}-bearing mapping
* function to the value of this {@link OptionalDouble}, if a value is
* present, otherwise an empty {@link OptionalDouble}
*/
public static OptionalDouble flatMapToDouble(final OptionalInt optional, final IntFunction<OptionalDouble> mapper) {
return optional.isPresent() ? mapper.apply(optional.getAsInt()) : OptionalDouble.empty();
}
/**
* If a value is present, apply the provided {@link OptionalLong}-bearing
* mapping function to it, return that result, otherwise return an empty
* {@link OptionalLong}. This method is similar to
* {@link #mapToLong(OptionalInt, IntToLongFunction)}, but the provided mapper
* is one whose result is already an {@code OptionalLong}, and if invoked,
* {@code flatMapToDouble} does not wrap it with an additional
* {@link OptionalLong}.
*
* @param optional optional value
* @param mapper a mapping function to apply to the value, if present the
* mapping function
* @return the result of applying an {@link OptionalLong}-bearing mapping
* function to the value of this {@link OptionalLong}, if a value is
* present, otherwise an empty {@link OptionalLong}
*/
public static OptionalLong flatMapToLong(final OptionalInt optional, final IntFunction<OptionalLong> mapper) {
return optional.isPresent() ? mapper.apply(optional.getAsInt()) : OptionalLong.empty();
}
/**
* If a value is present, apply the provided {@link Optional}-bearing mapping
* function to it, return that result, otherwise return an empty
* {@link Optional}. This method is similar to
* {@link #mapToObj(OptionalInt, IntFunction)}, but the provided mapper is one
* whose result is already an {@code Optional}, and if invoked,
* {@code flatMapToDouble} does not wrap it with an additional {@link Optional}.
*
* @param <T> the type parameter to the {@code Optional} returned
* @param optional optional value
* @param mapper a mapping function to apply to the value, if present the
* mapping function
* @return the result of applying an {@link Optional}-bearing mapping function
* to the value of this {@link Optional}, if a value is present,
* otherwise an empty {@link Optional}
*/
public static <T> Optional<T> flatMapToObj(final OptionalInt optional, final IntFunction<Optional<T>> mapper) {
return optional.isPresent() ? mapper.apply(optional.getAsInt()) : Optional.empty();
}
/**
* If a value is present, applies {@code mapper} to {@code optional} and returns
* an {@link OptionalInt} describing the result. Otherwise returns an empty
* {@link OptionalInt}.
*
* @param optional optional value
* @param mapper a mapping function to apply to the value, if present
* @return an {@link OptionalInt} describing the result of applying
* {@code mapper} function to the value of {@code optional}, if a value
* is present, otherwise an empty {@link OptionalInt}
*/
public static OptionalInt map(final OptionalInt optional, final IntToIntFunction mapper) {
return optional.isPresent() ? OptionalInt.of(mapper.applyAsInt(optional.getAsInt())) : OptionalInt.empty();
}
/**
* If a value is present, applies {@code mapper} to {@code optional} and returns
* an {@link OptionalDouble} describing the result. Otherwise returns an empty
* {@link OptionalDouble}.
*
* @param optional optional value
* @param mapper a mapping function to apply to the value, if present
* @return an {@link OptionalDouble} describing the result of applying
* {@code mapper} function to the value of {@code optional}, if a value
* is present, otherwise an empty {@link OptionalDouble}
*/
public static OptionalDouble mapToDouble(final OptionalInt optional, final IntToDoubleFunction mapper) {
return optional.isPresent() ? OptionalDouble.of(mapper.applyAsDouble(optional.getAsInt())) : OptionalDouble.empty();
}
/**
* If a value is present, applies {@code mapper} to {@code optional} and returns
* an {@link OptionalLong} describing the result. Otherwise returns an empty
* {@link OptionalLong}.
*
* @param optional optional value
* @param mapper a mapping function to apply to the value, if present
* @return an {@link OptionalLong} describing the result of applying
* {@code mapper} function to the value of {@code optional}, if a value
* is present, otherwise an empty {@link OptionalLong}
*/
public static OptionalLong mapToLong(final OptionalInt optional, final IntToLongFunction mapper) {
return optional.isPresent() ? OptionalLong.of(mapper.applyAsLong(optional.getAsInt())) : OptionalLong.empty();
}
/**
* If a value is present, applies {@code mapper} to {@code optional} and returns
* an {@link Optional} describing the result. Otherwise returns an empty
* {@link Optional}.
*
* @param <T> the type of the result of {@code mapper}
* @param optional optional value
* @param mapper a mapping function to apply to the value, if present
* @return an {@link Optional} describing the result of applying {@code mapper}
* function to the value of {@code optional}, if a value is present,
* otherwise an empty {@link Optional}
*/
public static <T> Optional<T> mapToObj(final OptionalInt optional, final IntFunction<T> mapper) {
return optional.isPresent() ? Optional.ofNullable(mapper.apply(optional.getAsInt())) : Optional.empty();
}
/**
* Returns an {@link OptionalInt} describing the specified value, if non-empty,
* otherwise returns an empty {@link OptionalInt}. The term <i>empty</i> is
* described by {@code isEmpty}.
*
* @param isEmpty predicate describing the term <i>empty</i>
* @param value the possibly-empty value to describe
* @return an {@link OptionalInt} with a present value if the specified value is
* non-empty, otherwise an empty {@link OptionalInt}
*/
public static OptionalInt ofNon(final IntPredicate isEmpty, final int value) {
return isEmpty.test(value) ? OptionalInt.empty() : OptionalInt.of(value);
}
/**
* Returns an {@link OptionalInt} describing the specified value, if non-null,
* otherwise returns an empty {@link OptionalInt}.
*
* @param value the possibly-null value to describe
* @return an {@link OptionalInt} with a present value if the specified value is
* non-null, otherwise an empty {@link OptionalInt}
*/
public static OptionalInt ofNullable(@Nullable final Integer value) {
return value == null ? OptionalInt.empty() : OptionalInt.of(value);
}
/**
* Returns a stream consisting of present elements.
*
* @param optionals array of optional elements
* @return the new stream
*/
@SafeVarargs
public static IntStream stream(final OptionalInt... optionals) {
return Arrays.stream(optionals).filter(OptionalInt::isPresent).mapToInt(OptionalInt::getAsInt);
}
@java.lang.SuppressWarnings("all")
@edu.umd.cs.findbugs.annotations.SuppressFBWarnings(justification = "generated code")
@lombok.Generated
private OptionalInts() {
throw new java.lang.UnsupportedOperationException("This is a utility class and cannot be instantiated");
}
}