src/main/java/org/apache/commons/lang3/IntegerRange.java

/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You 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
 *
 *      https://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.apache.commons.lang3;

import java.util.stream.IntStream;

/**
 * Specializes {@link NumberRange} for {@link Integer}s.
 *
 * <p>
 * This class is not designed to interoperate with other NumberRanges
 * </p>
 *
 * @since 3.13.0
 */
public final class IntegerRange extends NumberRange<Integer> {

    private static final long serialVersionUID = 1L;

    /**
     * Creates a closed range with the specified minimum and maximum values (both inclusive).
     *
     * <p>
     * The range uses the natural ordering of the elements to determine where values lie in the range.
     * </p>
     *
     * <p>
     * The arguments may be passed in the order (min,max) or (max,min). The getMinimum and getMaximum methods will return the correct values.
     * </p>
     *
     * @param fromInclusive the first value that defines the edge of the range, inclusive.
     * @param toInclusive the second value that defines the edge of the range, inclusive.
     * @return the range object, not null.
     */
    public static IntegerRange of(final int fromInclusive, final int toInclusive) {
        return of(Integer.valueOf(fromInclusive), Integer.valueOf(toInclusive));
    }

    /**
     * Creates a closed range with the specified minimum and maximum values (both inclusive).
     *
     * <p>
     * The range uses the natural ordering of the elements to determine where values lie in the range.
     * </p>
     *
     * <p>
     * The arguments may be passed in the order (min,max) or (max,min). The getMinimum and getMaximum methods will return the correct values.
     * </p>
     *
     * @param fromInclusive the first value that defines the edge of the range, inclusive.
     * @param toInclusive the second value that defines the edge of the range, inclusive.
     * @return the range object, not null.
     * @throws IllegalArgumentException if either element is null.
     */
    public static IntegerRange of(final Integer fromInclusive, final Integer toInclusive) {
        return new IntegerRange(fromInclusive, toInclusive);
    }

    /**
     * Creates a new instance.
     *
     * @param number1 the first element, not null
     * @param number2 the second element, not null
     * @throws NullPointerException when element1 is null.
     * @throws NullPointerException when element2 is null.
     */
    private IntegerRange(final Integer number1, final Integer number2) {
        super(number1, number2, null);
    }

    /**
     * Fits the given value into this range by returning the given value or, if out of bounds, the range minimum if
     * below, or the range maximum if above.
     *
     * <pre>{@code
     * IntegerRange range = IntegerRange.of(16, 64);
     * range.fit(-9) -->  16
     * range.fit(0)  -->  16
     * range.fit(15) -->  16
     * range.fit(16) -->  16
     * range.fit(17) -->  17
     * ...
     * range.fit(63) -->  63
     * range.fit(64) -->  64
     * range.fit(99) -->  64
     * }</pre>
     *
     * @param element the element to test.
     * @return the minimum, the element, or the maximum depending on the element's location relative to the range.
     * @since 3.19.0
     */
    public int fit(final int element) {
        return super.fit(element).intValue();
    }

    /**
     * Returns a sequential ordered {@code IntStream} from {@link #getMinimum()} (inclusive) to {@link #getMaximum()} (inclusive) by an incremental step of
     * {@code 1}.
     *
     * @return a sequential {@code IntStream} for the range of {@code int} elements
     * @since 3.18.0
     */
    public IntStream toIntStream() {
        return IntStream.rangeClosed(getMinimum(), getMaximum());
    }
}