onl.area51.httpd.action.HttpFunction.java Source code

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Here is the source code for onl.area51.httpd.action.HttpFunction.java

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package onl.area51.httpd.action;

import java.io.IOException;
import java.io.UncheckedIOException;
import java.util.Objects;
import java.util.function.Function;
import org.apache.http.HttpException;

/**
 *
 * @author peter
 * @param <T>
 * @param <R>
 */
@FunctionalInterface
public interface HttpFunction<T, R> {

    R apply(T v) throws HttpException, IOException;

    /**
     * Convert this consumer into a standard {@link Consumer}.
     * <p>
     * When an {@link IOException} is thrown then an {@link UncheckedIOException} will be thrown instead.
     * <p>
     * @return consumer
     */
    default Function<T, R> guard() {
        return guard(this);
    }

    /**
     * Convert an {@link IOConsumer} into a standard {@link Consumer}.
     * <p>
     * When an {@link IOException} is thrown then an {@link UncheckedIOException} will be thrown instead.
     * <p>
     * @param <V>
     * @param <T>
     * @param c IOConsumer to guard
     * <p>
     * @return consumer
     */
    static <V, T> Function<V, T> guard(HttpFunction<V, T> c) {
        return v -> {
            try {
                return c.apply(v);
            } catch (HttpException ex) {
                throw new RuntimeException(ex);
            } catch (IOException ex) {
                throw new UncheckedIOException(ex);
            }
        };
    }

    default <V> HttpFunction<V, R> compose(HttpFunction<? super V, ? extends T> before) {
        Objects.requireNonNull(before);
        return (V v) -> apply(before.apply(v));
    }

    default <V> HttpFunction<T, V> andThen(HttpFunction<? super R, ? extends V> after) {
        Objects.requireNonNull(after);
        return (T t) -> after.apply(apply(t));
    }

}