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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. */ // Rwevised from commons lang Apache /** * A mutable <code>int</code> wrapper. * * @see Integer * @since 2.1 * @version $Id: MutableInt.java 437554 2006-08-28 06:21:41Z bayard $ */ public class MutableInt extends Number implements Comparable, Mutable { /** * Required for serialization support. * * @see java.io.Serializable */ private static final long serialVersionUID = 512176391864L; /** The mutable value. */ private int value; /** * Constructs a new MutableInt with the default value of zero. */ public MutableInt() { super(); } /** * Constructs a new MutableInt with the specified value. * * @param value * a value. */ public MutableInt(int value) { super(); this.value = value; } /** * Constructs a new MutableInt with the specified value. * * @param value * a value. * @throws NullPointerException * if the object is null */ public MutableInt(Number value) { super(); this.value = value.intValue(); } //----------------------------------------------------------------------- /** * Gets the value as a Integer instance. * * @return the value as a Integer */ public Object getValue() { return new Integer(this.value); } /** * Sets the value. * * @param value * the value to set */ public void setValue(int value) { this.value = value; } /** * Sets the value from any Number instance. * * @param value * the value to set * @throws NullPointerException * if the object is null * @throws ClassCastException * if the type is not a {@link Number} */ public void setValue(Object value) { setValue(((Number) value).intValue()); } //----------------------------------------------------------------------- /** * Increments the value. * * @since Commons Lang 2.2 */ public void increment() { value++; } /** * Decrements the value. * * @since Commons Lang 2.2 */ public void decrement() { value--; } //----------------------------------------------------------------------- /** * Adds a value. * * @param operand * the value to add * * @since Commons Lang 2.2 */ public void add(int operand) { this.value += operand; } /** * Adds a value. * * @param operand * the value to add * @throws NullPointerException * if the object is null * * @since Commons Lang 2.2 */ public void add(Number operand) { this.value += operand.intValue(); } /** * Subtracts a value. * * @param operand * the value to add * * @since Commons Lang 2.2 */ public void subtract(int operand) { this.value -= operand; } /** * Subtracts a value. * * @param operand * the value to add * @throws NullPointerException * if the object is null * * @since Commons Lang 2.2 */ public void subtract(Number operand) { this.value -= operand.intValue(); } //----------------------------------------------------------------------- // shortValue and bytValue rely on Number implementation /** * Returns the value of this MutableInt as a int. * * @return the numeric value represented by this object after conversion to type int. */ public int intValue() { return value; } /** * Returns the value of this MutableInt as a long. * * @return the numeric value represented by this object after conversion to type long. */ public long longValue() { return value; } /** * Returns the value of this MutableInt as a float. * * @return the numeric value represented by this object after conversion to type float. */ public float floatValue() { return value; } /** * Returns the value of this MutableInt as a double. * * @return the numeric value represented by this object after conversion to type double. */ public double doubleValue() { return value; } //----------------------------------------------------------------------- /** * Gets this mutable as an instance of Integer. * * @return a Integer instance containing the value from this mutable */ public Integer toInteger() { return new Integer(intValue()); } //----------------------------------------------------------------------- /** * Compares this object to the specified object. The result is <code>true</code> if and only if the argument is * not <code>null</code> and is an <code>MutableInt</code> object that contains the same <code>int</code> value * as this object. * * @param obj * the object to compare with. * @return <code>true</code> if the objects are the same; <code>false</code> otherwise. */ public boolean equals(Object obj) { if (obj instanceof MutableInt) { return value == ((MutableInt) obj).intValue(); } return false; } /** * Returns a suitable hashcode for this mutable. * * @return a suitable hashcode */ public int hashCode() { return value; } /** * Compares this mutable to another in ascending order. * * @param obj * the mutable to compare to * @return negative if this is less, zero if equal, positive if greater * @throws ClassCastException if the argument is not a MutableInt */ public int compareTo(Object obj) { MutableInt other = (MutableInt) obj; int anotherVal = other.value; return value < anotherVal ? -1 : (value == anotherVal ? 0 : 1); } /** * Returns the String value of this mutable. * * @return the mutable value as a string */ public String toString() { return String.valueOf(value); } } /* * 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. */ /** * Provides mutable access to a value. * <p> * <code>Mutable</code> is used as a generic interface to the implementations * in this package. * <p> * A typical use case would be to enable a primitive or string to be passed to a * method and allow that method to effectively change the value of the * primitive/string. Another use case is to store a frequently changing * primitive in a collection (for example a total in a map) without needing to * create new Integer/Long wrapper objects. * * @author Matthew Hawthorne * @since 2.1 * @version $Id: Mutable.java 618693 2008-02-05 16:33:29Z sebb $ */ interface Mutable { /** * Gets the value of this mutable. * * @return the stored value */ Object getValue(); /** * Sets the value of this mutable. * * @param value * the value to store * @throws NullPointerException * if the object is null and null is invalid * @throws ClassCastException * if the type is invalid */ void setValue(Object value); }