Java tutorial
/* * Derived from code that was licensed to the Apache Software Foundation (ASF) under one or more * contributor license agreements. See the NOTICE file distributed with Apache Commons Lang 3 for * additional information regarding copyright ownership. * * Brandon Mintern and the ASF license 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 net.mintern.primitive.pair; /** * A pair modeled after {@link org.apache.commons.lang3.tuple.Pair} that consists of {@code char} * elements that allows users to avoid {@code Character} boxing. It refers to the elements as 'left' * and 'right'. * <p> * Subclass implementations may be mutable or immutable. * * @author Brandon Mintern */ public abstract class CharPair implements PrimitivePair<Character, Character>, Comparable<CharPair> { private static final long serialVersionUID = 1; /** * Obtains an immutable pair of the given {@code char} values. * * @param left the left element * @param right the right element * @return a pair formed from the two parameters, not null */ public static CharPair of(char left, char right) { return ImmutableCharPair.of(left, right); } /** * Gets the left element from this pair. * * @return the left element */ public abstract char getLeft(); /** * Gets the right element from this pair. * * @return the right element */ public abstract char getRight(); /** * Compares the pair based on the left element followed by the right element. * * @param other the other pair, not null * @return negative if this is less, zero if equal, positive if greater */ @Override public int compareTo(CharPair other) { int cmp = Character.compare(getLeft(), other.getLeft()); return cmp != 0 ? cmp : Character.compare(getRight(), other.getRight()); } /** * Compares this pair to another based on the two elements. * * @param obj the object to compare to, null returns false * @return true if the elements of the pair are equal */ @Override public boolean equals(Object obj) { if (obj == this) { return true; } if (obj instanceof CharPair) { CharPair o = (CharPair) obj; return getLeft() == o.getLeft() && getRight() == o.getRight(); } return false; } /** * Returns a hash code that follows the definition in {@link java.util.Map.Entry#hashCode()}. * * @return the hash code * @see Character#hashCode(char) */ @Override public int hashCode() { return Character.hashCode(getLeft()) ^ Character.hashCode(getRight()); } /** * Returns a String representation of this pair using the format {@code ($left,$right)}. * * @return a string describing this object, not null */ @Override public String toString() { return "(" + getLeft() + "," + getRight() + ")"; } }