Delete unused NonEmptyList class

pgpainless-core/src/main/java/org/pgpainless/util/NonEmptyList.java

@@ -1,88 +0,0 @@
-/*
- * Copyright 2021 Paul Schaub.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-package org.pgpainless.util;
-
-import java.util.Collections;
-import java.util.LinkedList;
-import java.util.List;
-import javax.annotation.Nonnull;
-
-/**
- * Utility class of an immutable list which cannot be empty.
- * The first element can be accessed via {@link #get()} which is guaranteed to return a non-null value.
- * The rest of the list can be accessed via {@link #getOthers()}, which is guaranteed to return a non-null list which is possibly empty.
- * Lastly, the whole list can be accessed via {@link #getAll()}, which is guaranteed to return a non-empty list.
- *
- * @param <E> element type
- */
-public class NonEmptyList<E> {
-
-    private final List<E> elements;
-
-    /**
-     * Create a singleton list from the given element.
-     *
-     * @param element element
-     */
-    public NonEmptyList(E element) {
-        if (element == null) {
-            throw new IllegalArgumentException("Singleton element cannot be null.");
-        }
-        this.elements = Collections.singletonList(element);
-    }
-
-    /**
-     * Create a non-empty list from the given list of elements.
-     *
-     * @param elements elements
-     * @throws IllegalArgumentException if the provided list of elements is empty.
-     */
-    public NonEmptyList(List<E> elements) {
-        if (elements.isEmpty()) {
-            throw new IllegalArgumentException("Underlying list cannot be empty.");
-        }
-        this.elements = Collections.unmodifiableList(elements);
-    }
-
-    /**
-     * Return the first element of the list.
-     *
-     * @return first
-     */
-    public @Nonnull E get() {
-        return elements.get(0);
-    }
-
-    /**
-     * Return a list of all elements of the list except the first.
-     *
-     * @return list of all but the first element
-     */
-    public @Nonnull List<E> getOthers() {
-        List<E> others = new LinkedList<>(elements);
-        others.remove(0);
-        return Collections.unmodifiableList(others);
-    }
-
-    /**
-     * Return a non-empty list of all elements of this list.
-     *
-     * @return all elements
-     */
-    public List<E> getAll() {
-        return elements;
-    }
-}