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/* * 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 * * 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.apache.commons.lang.math; /** * <p><code>Range</code> represents a range of numbers of the same type.</p> * * <p>Specific subclasses hold the range values as different types. Each * subclass should be immutable and {@link java.io.Serializable Serializable} * if possible.</p> * * @author Stephen Colebourne * @since 2.0 * @version $Id: Range.java 437554 2006-08-28 06:21:41Z bayard $ */ public abstract class Range { /** * <p>Constructs a new range.</p> */ public Range() { super(); } // Accessors //-------------------------------------------------------------------- /** * <p>Gets the minimum number in this range.</p> * * @return the minimum number in this range */ public abstract Number getMinimumNumber(); /** * <p>Gets the minimum number in this range as a <code>long</code>.</p> * * <p>This implementation uses the {@link #getMinimumNumber()} method. * Subclasses may be able to optimise this.</p> * * @return the minimum number in this range */ public long getMinimumLong() { return getMinimumNumber().longValue(); } /** * <p>Gets the minimum number in this range as a <code>int</code>.</p> * * <p>This implementation uses the {@link #getMinimumNumber()} method. * Subclasses may be able to optimise this.</p> * * @return the minimum number in this range */ public int getMinimumInteger() { return getMinimumNumber().intValue(); } /** * <p>Gets the minimum number in this range as a <code>double</code>.</p> * * <p>This implementation uses the {@link #getMinimumNumber()} method. * Subclasses may be able to optimise this.</p> * * @return the minimum number in this range */ public double getMinimumDouble() { return getMinimumNumber().doubleValue(); } /** * <p>Gets the minimum number in this range as a <code>float</code>.</p> * * <p>This implementation uses the {@link #getMinimumNumber()} method. * Subclasses may be able to optimise this.</p> * * @return the minimum number in this range */ public float getMinimumFloat() { return getMinimumNumber().floatValue(); } /** * <p>Gets the maximum number in this range.</p> * * @return the maximum number in this range */ public abstract Number getMaximumNumber(); /** * <p>Gets the maximum number in this range as a <code>long</code>.</p> * * <p>This implementation uses the {@link #getMaximumNumber()} method. * Subclasses may be able to optimise this.</p> * * @return the maximum number in this range */ public long getMaximumLong() { return getMaximumNumber().longValue(); } /** * <p>Gets the maximum number in this range as a <code>int</code>.</p> * * <p>This implementation uses the {@link #getMaximumNumber()} method. * Subclasses may be able to optimise this.</p> * * @return the maximum number in this range */ public int getMaximumInteger() { return getMaximumNumber().intValue(); } /** * <p>Gets the maximum number in this range as a <code>double</code>.</p> * * <p>This implementation uses the {@link #getMaximumNumber()} method. * Subclasses may be able to optimise this.</p> * * @return the maximum number in this range */ public double getMaximumDouble() { return getMaximumNumber().doubleValue(); } /** * <p>Gets the maximum number in this range as a <code>float</code>.</p> * * <p>This implementation uses the {@link #getMaximumNumber()} method. * Subclasses may be able to optimise this.</p> * * @return the maximum number in this range */ public float getMaximumFloat() { return getMaximumNumber().floatValue(); } // Include tests //-------------------------------------------------------------------- /** * <p>Tests whether the specified <code>Number</code> occurs within * this range.</p> * * <p>The exact comparison implementation varies by subclass. It is * intended that an <code>int</code> specific subclass will compare using * <code>int</code> comparison.</p> * * <p><code>null</code> is handled and returns <code>false</code>.</p> * * @param number the number to test, may be <code>null</code> * @return <code>true</code> if the specified number occurs within this range * @throws IllegalArgumentException if the <code>Number</code> cannot be compared */ public abstract boolean containsNumber(Number number); /** * <p>Tests whether the specified <code>Number</code> occurs within * this range using <code>long</code> comparison..</p> * * <p><code>null</code> is handled and returns <code>false</code>.</p> * * <p>This implementation forwards to the {@link #containsLong(long)} method.</p> * * @param value the long to test, may be <code>null</code> * @return <code>true</code> if the specified number occurs within this * range by <code>long</code> comparison */ public boolean containsLong(Number value) { if (value == null) { return false; } return containsLong(value.longValue()); } /** * <p>Tests whether the specified <code>long</code> occurs within * this range using <code>long</code> comparison.</p> * * <p>This implementation uses the {@link #getMinimumLong()} and * {@link #getMaximumLong()} methods and should be good for most uses.</p> * * @param value the long to test * @return <code>true</code> if the specified number occurs within this * range by <code>long</code> comparison */ public boolean containsLong(long value) { return value >= getMinimumLong() && value <= getMaximumLong(); } /** * <p>Tests whether the specified <code>Number</code> occurs within * this range using <code>int</code> comparison..</p> * * <p><code>null</code> is handled and returns <code>false</code>.</p> * * <p>This implementation forwards to the {@link #containsInteger(int)} method.</p> * * @param value the integer to test, may be <code>null</code> * @return <code>true</code> if the specified number occurs within this * range by <code>int</code> comparison */ public boolean containsInteger(Number value) { if (value == null) { return false; } return containsInteger(value.intValue()); } /** * <p>Tests whether the specified <code>int</code> occurs within * this range using <code>int</code> comparison.</p> * * <p>This implementation uses the {@link #getMinimumInteger()} and * {@link #getMaximumInteger()} methods and should be good for most uses.</p> * * @param value the int to test * @return <code>true</code> if the specified number occurs within this * range by <code>int</code> comparison */ public boolean containsInteger(int value) { return value >= getMinimumInteger() && value <= getMaximumInteger(); } /** * <p>Tests whether the specified <code>Number</code> occurs within * this range using <code>double</code> comparison..</p> * * <p><code>null</code> is handled and returns <code>false</code>.</p> * * <p>This implementation forwards to the {@link #containsDouble(double)} method.</p> * * @param value the double to test, may be <code>null</code> * @return <code>true</code> if the specified number occurs within this * range by <code>double</code> comparison */ public boolean containsDouble(Number value) { if (value == null) { return false; } return containsDouble(value.doubleValue()); } /** * <p>Tests whether the specified <code>double</code> occurs within * this range using <code>double</code> comparison.</p> * * <p>This implementation uses the {@link #getMinimumDouble()} and * {@link #getMaximumDouble()} methods and should be good for most uses.</p> * * @param value the double to test * @return <code>true</code> if the specified number occurs within this * range by <code>double</code> comparison */ public boolean containsDouble(double value) { int compareMin = NumberUtils.compare(getMinimumDouble(), value); int compareMax = NumberUtils.compare(getMaximumDouble(), value); return compareMin <= 0 && compareMax >= 0; } /** * <p>Tests whether the specified <code>Number</code> occurs within * this range using <code>float</code> comparison.</p> * * <p><code>null</code> is handled and returns <code>false</code>.</p> * * <p>This implementation forwards to the {@link #containsFloat(float)} method.</p> * * @param value the float to test, may be <code>null</code> * @return <code>true</code> if the specified number occurs within this * range by <code>float</code> comparison */ public boolean containsFloat(Number value) { if (value == null) { return false; } return containsFloat(value.floatValue()); } /** * <p>Tests whether the specified <code>float</code> occurs within * this range using <code>float</code> comparison.</p> * * <p>This implementation uses the {@link #getMinimumFloat()} and * {@link #getMaximumFloat()} methods and should be good for most uses.</p> * * @param value the float to test * @return <code>true</code> if the specified number occurs within this * range by <code>float</code> comparison */ public boolean containsFloat(float value) { int compareMin = NumberUtils.compare(getMinimumFloat(), value); int compareMax = NumberUtils.compare(getMaximumFloat(), value); return compareMin <= 0 && compareMax >= 0; } // Range tests //-------------------------------------------------------------------- /** * <p>Tests whether the specified range occurs entirely within this range.</p> * * <p>The exact comparison implementation varies by subclass. It is * intended that an <code>int</code> specific subclass will compare using * <code>int</code> comparison.</p> * * <p><code>null</code> is handled and returns <code>false</code>.</p> * * <p>This implementation uses the {@link #containsNumber(Number)} method. * Subclasses may be able to optimise this.</p> * * @param range the range to test, may be <code>null</code> * @return <code>true</code> if the specified range occurs entirely within * this range; otherwise, <code>false</code> * @throws IllegalArgumentException if the <code>Range</code> cannot be compared */ public boolean containsRange(Range range) { if (range == null) { return false; } return containsNumber(range.getMinimumNumber()) && containsNumber(range.getMaximumNumber()); } /** * <p>Tests whether the specified range overlaps with this range.</p> * * <p>The exact comparison implementation varies by subclass. It is * intended that an <code>int</code> specific subclass will compare using * <code>int</code> comparison.</p> * * <p><code>null</code> is handled and returns <code>false</code>.</p> * * <p>This implementation uses the {@link #containsNumber(Number)} and * {@link #containsRange(Range)} methods. * Subclasses may be able to optimise this.</p> * * @param range the range to test, may be <code>null</code> * @return <code>true</code> if the specified range overlaps with this * range; otherwise, <code>false</code> * @throws IllegalArgumentException if the <code>Range</code> cannot be compared */ public boolean overlapsRange(Range range) { if (range == null) { return false; } return range.containsNumber(getMinimumNumber()) || range.containsNumber(getMaximumNumber()) || containsNumber(range.getMinimumNumber()); } // Basics //-------------------------------------------------------------------- /** * <p>Compares this range to another object to test if they are equal.</p>. * * <p>To be equal, the class, minimum and maximum must be equal.</p> * * <p>This implementation uses the {@link #getMinimumNumber()} and * {@link #getMaximumNumber()} methods. * Subclasses may be able to optimise this.</p> * * @param obj the reference object with which to compare * @return <code>true</code> if this object is equal */ public boolean equals(Object obj) { if (obj == this) { return true; } else if (obj == null || obj.getClass() != getClass()) { return false; } else { Range range = (Range) obj; return getMinimumNumber().equals(range.getMinimumNumber()) && getMaximumNumber().equals(range.getMaximumNumber()); } } /** * <p>Gets a hashCode for the range.</p> * * <p>This implementation uses the {@link #getMinimumNumber()} and * {@link #getMaximumNumber()} methods. * Subclasses may be able to optimise this.</p> * * @return a hash code value for this object */ public int hashCode() { int result = 17; result = 37 * result + getClass().hashCode(); result = 37 * result + getMinimumNumber().hashCode(); result = 37 * result + getMaximumNumber().hashCode(); return result; } /** * <p>Gets the range as a <code>String</code>.</p> * * <p>The format of the String is 'Range[<i>min</i>,<i>max</i>]'.</p> * * <p>This implementation uses the {@link #getMinimumNumber()} and * {@link #getMaximumNumber()} methods. * Subclasses may be able to optimise this.</p> * * @return the <code>String</code> representation of this range */ public String toString() { StringBuffer buf = new StringBuffer(32); buf.append("Range["); buf.append(getMinimumNumber()); buf.append(','); buf.append(getMaximumNumber()); buf.append(']'); return buf.toString(); } }