Java tutorial
/* * 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.lang3.mutable; import java.io.Serializable; import org.apache.commons.lang3.BooleanUtils; /** * A mutable <code>boolean</code> wrapper. * <p> * Note that as MutableBoolean does not extend Boolean, it is not treated by String.format as a Boolean parameter. * * @see Boolean * @since 2.2 * @version $Id$ */ public class MutableBoolean implements Mutable<Boolean>, Serializable, Comparable<MutableBoolean> { /** * Required for serialization support. * * @see java.io.Serializable */ private static final long serialVersionUID = -4830728138360036487L; /** The mutable value. */ private boolean value; /** * Constructs a new MutableBoolean with the default value of false. */ public MutableBoolean() { super(); } /** * Constructs a new MutableBoolean with the specified value. * * @param value the initial value to store */ public MutableBoolean(final boolean value) { super(); this.value = value; } /** * Constructs a new MutableBoolean with the specified value. * * @param value the initial value to store, not null * @throws NullPointerException if the object is null */ public MutableBoolean(final Boolean value) { super(); this.value = value.booleanValue(); } //----------------------------------------------------------------------- /** * Gets the value as a Boolean instance. * * @return the value as a Boolean, never null */ @Override public Boolean getValue() { return Boolean.valueOf(this.value); } /** * Sets the value. * * @param value the value to set */ public void setValue(final boolean value) { this.value = value; } /** * Sets the value to true. * * @since 3.3 */ public void setFalse() { this.value = false; } /** * Sets the value to false. * * @since 3.3 */ public void setTrue() { this.value = true; } /** * Sets the value from any Boolean instance. * * @param value the value to set, not null * @throws NullPointerException if the object is null */ @Override public void setValue(final Boolean value) { this.value = value.booleanValue(); } //----------------------------------------------------------------------- /** * Checks if the current value is <code>true</code>. * * @return <code>true</code> if the current value is <code>true</code> * @since 2.5 */ public boolean isTrue() { return value == true; } /** * Checks if the current value is <code>false</code>. * * @return <code>true</code> if the current value is <code>false</code> * @since 2.5 */ public boolean isFalse() { return value == false; } //----------------------------------------------------------------------- /** * Returns the value of this MutableBoolean as a boolean. * * @return the boolean value represented by this object. */ public boolean booleanValue() { return value; } //----------------------------------------------------------------------- /** * Gets this mutable as an instance of Boolean. * * @return a Boolean instance containing the value from this mutable, never null * @since 2.5 */ public Boolean toBoolean() { return Boolean.valueOf(booleanValue()); } //----------------------------------------------------------------------- /** * 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>MutableBoolean</code> object that contains the same * <code>boolean</code> value as this object. * * @param obj the object to compare with, null returns false * @return <code>true</code> if the objects are the same; <code>false</code> otherwise. */ @Override public boolean equals(final Object obj) { if (obj instanceof MutableBoolean) { return value == ((MutableBoolean) obj).booleanValue(); } return false; } /** * Returns a suitable hash code for this mutable. * * @return the hash code returned by <code>Boolean.TRUE</code> or <code>Boolean.FALSE</code> */ @Override public int hashCode() { return value ? Boolean.TRUE.hashCode() : Boolean.FALSE.hashCode(); } //----------------------------------------------------------------------- /** * Compares this mutable to another in ascending order. * * @param other the other mutable to compare to, not null * @return negative if this is less, zero if equal, positive if greater * where false is less than true */ @Override public int compareTo(final MutableBoolean other) { return BooleanUtils.compare(this.value, other.value); } //----------------------------------------------------------------------- /** * Returns the String value of this mutable. * * @return the mutable value as a string */ @Override public String toString() { return String.valueOf(value); } }