/*
 * 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.mutable;

import org.apache.commons.lang.math.NumberUtils;

A mutable float wrapper.
Author:
Apache Software Foundation
See Also:
Float
Since:
2.1
Version:
$Id: MutableFloat.java 905707 2010-02-02 16:59:59Z niallp $/**
 * A mutable <code>float</code> wrapper.
 * 
 * @see Float
 * @since 2.1
 * @author Apache Software Foundation
 * @version $Id: MutableFloat.java 905707 2010-02-02 16:59:59Z niallp $
 */
public class MutableFloat extends Number implements Comparable, Mutable {

    
Required for serialization support.
See Also:
Serializable/**
     * Required for serialization support.
     * 
     * @see java.io.Serializable
     */
    private static final long serialVersionUID = 5787169186L;

    
The mutable value. /** The mutable value. */
    private float value;

    
Constructs a new MutableFloat with the default value of zero.
/**
     * Constructs a new MutableFloat with the default value of zero.
     */
    public MutableFloat() {
        super();
    }

    
Constructs a new MutableFloat with the specified value.
Params:
value –  the initial value to store/**
     * Constructs a new MutableFloat with the specified value.
     * 
     * @param value  the initial value to store
     */
    public MutableFloat(float value) {
        super();
        this.value = value;
    }

    
Constructs a new MutableFloat with the specified value.
Params:
value –  the initial value to store, not null
Throws:
NullPointerException – if the object is null/**
     * Constructs a new MutableFloat with the specified value.
     * 
     * @param value  the initial value to store, not null
     * @throws NullPointerException if the object is null
     */
    public MutableFloat(Number value) {
        super();
        this.value = value.floatValue();
    }

    
Constructs a new MutableFloat parsing the given string.
Params:
value –  the string to parse, not null
Throws:
NumberFormatException – if the string cannot be parsed into a float
Since:
2.5/**
     * Constructs a new MutableFloat parsing the given string.
     * 
     * @param value  the string to parse, not null
     * @throws NumberFormatException if the string cannot be parsed into a float
     * @since 2.5
     */
    public MutableFloat(String value) throws NumberFormatException {
        super();
        this.value = Float.parseFloat(value);
    }

    //-----------------------------------------------------------------------
    
Gets the value as a Float instance.
Returns:
the value as a Float, never null/**
     * Gets the value as a Float instance.
     * 
     * @return the value as a Float, never null
     */
    public Object getValue() {
        return new Float(this.value);
    }

    
Sets the value.
Params:
value –  the value to set/**
     * Sets the value.
     * 
     * @param value  the value to set
     */
    public void setValue(float value) {
        this.value = value;
    }

    
Sets the value from any Number instance.
Params:
value –  the value to set, not null
Throws:
NullPointerException – if the object is null
ClassCastException – if the type is not a Number/**
     * Sets the value from any Number instance.
     * 
     * @param value  the value to set, not null
     * @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).floatValue());
    }

    //-----------------------------------------------------------------------
    
Checks whether the float value is the special NaN value.
Returns:
true if NaN/**
     * Checks whether the float value is the special NaN value.
     * 
     * @return true if NaN
     */
    public boolean isNaN() {
        return Float.isNaN(value);
    }

    
Checks whether the float value is infinite.
Returns:
true if infinite/**
     * Checks whether the float value is infinite.
     * 
     * @return true if infinite
     */
    public boolean isInfinite() {
        return Float.isInfinite(value);
    }

    //-----------------------------------------------------------------------
    
Increments the value.
Since:
Commons Lang 2.2/**
     * Increments the value.
     *
     * @since Commons Lang 2.2
     */
    public void increment() {
        value++;
    }

    
Decrements the value.
Since:
Commons Lang 2.2/**
     * Decrements the value.
     *
     * @since Commons Lang 2.2
     */
    public void decrement() {
        value--;
    }

    //-----------------------------------------------------------------------
    
Adds a value to the value of this instance.
Params:
operand –  the value to add, not null
Since:
Commons Lang 2.2/**
     * Adds a value to the value of this instance.
     * 
     * @param operand  the value to add, not null
     * @since Commons Lang 2.2
     */
    public void add(float operand) {
        this.value += operand;
    }

    
Adds a value to the value of this instance.
Params:
operand –  the value to add, not null
Throws:
NullPointerException – if the object is null
Since:
Commons Lang 2.2/**
     * Adds a value to the value of this instance.
     * 
     * @param operand  the value to add, not null
     * @throws NullPointerException if the object is null
     * @since Commons Lang 2.2
     */
    public void add(Number operand) {
        this.value += operand.floatValue();
    }

    
Subtracts a value from the value of this instance.
Params:
operand –  the value to subtract
Since:
Commons Lang 2.2/**
     * Subtracts a value from the value of this instance.
     * 
     * @param operand  the value to subtract
     * @since Commons Lang 2.2
     */
    public void subtract(float operand) {
        this.value -= operand;
    }

    
Subtracts a value from the value of this instance.
Params:
operand –  the value to subtract, not null
Throws:
NullPointerException – if the object is null
Since:
Commons Lang 2.2/**
     * Subtracts a value from the value of this instance.
     * 
     * @param operand  the value to subtract, not null
     * @throws NullPointerException if the object is null
     * @since Commons Lang 2.2
     */
    public void subtract(Number operand) {
        this.value -= operand.floatValue();
    }

    //-----------------------------------------------------------------------
    // shortValue and bytValue rely on Number implementation
    
Returns the value of this MutableFloat as an int.
Returns:
the numeric value represented by this object after conversion to type int./**
     * Returns the value of this MutableFloat as an int.
     *
     * @return the numeric value represented by this object after conversion to type int.
     */
    public int intValue() {
        return (int) value;
    }

    
Returns the value of this MutableFloat as a long.
Returns:
the numeric value represented by this object after conversion to type long./**
     * Returns the value of this MutableFloat as a long.
     *
     * @return the numeric value represented by this object after conversion to type long.
     */
    public long longValue() {
        return (long) value;
    }

    
Returns the value of this MutableFloat as a float.
Returns:
the numeric value represented by this object after conversion to type float./**
     * Returns the value of this MutableFloat 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 MutableFloat as a double.
Returns:
the numeric value represented by this object after conversion to type double./**
     * Returns the value of this MutableFloat 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 Float.
Returns:
a Float instance containing the value from this mutable, never null/**
     * Gets this mutable as an instance of Float.
     *
     * @return a Float instance containing the value from this mutable, never null
     */
    public Float toFloat() {
        return new Float(floatValue());
    }

    //-----------------------------------------------------------------------
    
Compares this object against some other object. The result is true if and only if the argument is
not null and is a Float object that represents a float that has the
identical bit pattern to the bit pattern of the float represented by this object. For this purpose, two float values are considered to be the same if and only if the method Float.floatToIntBits(float)returns the same int value when applied to each. 

Note that in most cases, for two instances of class Float,f1 and f2,
the value of f1.equals(f2) is true if and only if 

  f1.floatValue() == f2.floatValue()



also has the value true. However, there are two exceptions:

If f1 and f2 both represent Float.NaN, then the
equals method returns true, even though Float.NaN==Float.NaN has
the value false.
If f1 represents +0.0f while f2 represents -0.0f,
or vice versa, the equal test has the value false, even though
0.0f==-0.0f has the value true.

This definition allows hashtables to operate properly.
Params:
obj –  the object to compare with, null returns false
See Also:
Float.floatToIntBits(float)
Returns:
true if the objects are the same; false otherwise./**
     * Compares this object against some other object. The result is <code>true</code> if and only if the argument is
     * not <code>null</code> and is a <code>Float</code> object that represents a <code>float</code> that has the
     * identical bit pattern to the bit pattern of the <code>float</code> represented by this object. For this
     * purpose, two float values are considered to be the same if and only if the method
     * {@link Float#floatToIntBits(float)}returns the same int value when applied to each.
     * <p>
     * Note that in most cases, for two instances of class <code>Float</code>,<code>f1</code> and <code>f2</code>,
     * the value of <code>f1.equals(f2)</code> is <code>true</code> if and only if <blockquote>
     * 
     * <pre>
     *   f1.floatValue() == f2.floatValue()
     * </pre>
     * 
     * </blockquote>
     * <p>
     * also has the value <code>true</code>. However, there are two exceptions:
     * <ul>
     * <li>If <code>f1</code> and <code>f2</code> both represent <code>Float.NaN</code>, then the
     * <code>equals</code> method returns <code>true</code>, even though <code>Float.NaN==Float.NaN</code> has
     * the value <code>false</code>.
     * <li>If <code>f1</code> represents <code>+0.0f</code> while <code>f2</code> represents <code>-0.0f</code>,
     * or vice versa, the <code>equal</code> test has the value <code>false</code>, even though
     * <code>0.0f==-0.0f</code> has the value <code>true</code>.
     * </ul>
     * This definition allows hashtables to operate properly.
     * 
     * @param obj  the object to compare with, null returns false
     * @return <code>true</code> if the objects are the same; <code>false</code> otherwise.
     * @see java.lang.Float#floatToIntBits(float)
     */
    public boolean equals(Object obj) {
        return (obj instanceof MutableFloat)
            && (Float.floatToIntBits(((MutableFloat) obj).value) == Float.floatToIntBits(value));
    }

    
Returns a suitable hash code for this mutable.
Returns:
a suitable hash code/**
     * Returns a suitable hash code for this mutable.
     * 
     * @return a suitable hash code
     */
    public int hashCode() {
        return Float.floatToIntBits(value);
    }

    //-----------------------------------------------------------------------
    
Compares this mutable to another in ascending order.
Params:
obj – the other mutable to compare to, not null
Returns:
negative if this is less, zero if equal, positive if greater/**
     * Compares this mutable to another in ascending order.
     * 
     * @param obj the other mutable to compare to, not null
     * @return negative if this is less, zero if equal, positive if greater
     */
    public int compareTo(Object obj) {
        MutableFloat other = (MutableFloat) obj;
        float anotherVal = other.value;
        return NumberUtils.compare(value, anotherVal);
    }

    //-----------------------------------------------------------------------
    
Returns the String value of this mutable.
Returns:
the mutable value as a string/**
     * Returns the String value of this mutable.
     * 
     * @return the mutable value as a string
     */
    public String toString() {
        return String.valueOf(value);
    }

}