001/*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements.  See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License.  You may obtain a copy of the License at
008 *
009 *      https://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017package org.apache.commons.lang3.mutable;
018
019import java.util.concurrent.atomic.DoubleAccumulator;
020import java.util.concurrent.atomic.DoubleAdder;
021
022/**
023 * A mutable {@code float} wrapper.
024 * <p>
025 * This class was created before the introduction of the {@link java.util.concurrent.atomic} package and the {@link DoubleAccumulator} class.
026 * </p>
027 * <p>
028 * Note that as MutableFloat does not extend Float, it is not treated by String.format as a Float parameter.
029 * </p>
030 *
031 * @see Float
032 * @see DoubleAccumulator
033 * @see DoubleAdder
034 * @since 2.1
035 */
036public class MutableFloat extends Number implements Comparable<MutableFloat>, Mutable<Number> {
037
038    /**
039     * Required for serialization support.
040     *
041     * @see java.io.Serializable
042     */
043    private static final long serialVersionUID = 5787169186L;
044
045    /** The mutable value. */
046    private float value;
047
048    /**
049     * Constructs a new MutableFloat with the default value of zero.
050     */
051    public MutableFloat() {
052    }
053
054    /**
055     * Constructs a new MutableFloat with the specified value.
056     *
057     * @param value  The initial value to store.
058     */
059    public MutableFloat(final float value) {
060        this.value = value;
061    }
062
063    /**
064     * Constructs a new MutableFloat with the specified value.
065     *
066     * @param value  The initial value to store, not null.
067     * @throws NullPointerException Thrown if the object is null.
068     */
069    public MutableFloat(final Number value) {
070        this.value = value.floatValue();
071    }
072
073    /**
074     * Constructs a new MutableFloat parsing the given string.
075     *
076     * @param value  The string to parse, not null.
077     * @throws NumberFormatException Thrown if the string cannot be parsed into a float, see {@link Float#parseFloat(String)}.
078     * @since 2.5
079     */
080    public MutableFloat(final String value) {
081        this.value = Float.parseFloat(value);
082    }
083
084    /**
085     * Adds a value to the value of this instance.
086     *
087     * @param operand  The value to add, not null.
088     * @since 2.2
089     */
090    public void add(final float operand) {
091        this.value += operand;
092    }
093
094    /**
095     * Adds a value to the value of this instance.
096     *
097     * @param operand  The value to add, not null.
098     * @throws NullPointerException Thrown if the object is null.
099     * @since 2.2
100     */
101    public void add(final Number operand) {
102        this.value += operand.floatValue();
103    }
104
105    /**
106     * Increments this instance's value by {@code operand}; this method returns the value associated with the instance
107     * immediately after the addition operation. This method is not thread safe.
108     *
109     * @param operand The quantity to add, not null.
110     * @return The value associated with this instance after adding the operand.
111     * @since 3.5
112     */
113    public float addAndGet(final float operand) {
114        this.value += operand;
115        return value;
116    }
117
118    /**
119     * Increments this instance's value by {@code operand}; this method returns the value associated with the instance
120     * immediately after the addition operation. This method is not thread safe.
121     *
122     * @param operand The quantity to add, not null.
123     * @throws NullPointerException Thrown if {@code operand} is null.
124     * @return The value associated with this instance after adding the operand.
125     * @since 3.5
126     */
127    public float addAndGet(final Number operand) {
128        this.value += operand.floatValue();
129        return value;
130    }
131
132    /**
133     * Compares this mutable to another in ascending order.
134     *
135     * @param other  The other mutable to compare to, not null.
136     * @return negative if this is less, zero if equal, positive if greater.
137     */
138    @Override
139    public int compareTo(final MutableFloat other) {
140        return Float.compare(this.value, other.value);
141    }
142
143    /**
144     * Decrements the value.
145     *
146     * @since 2.2
147     */
148    public void decrement() {
149        value--;
150    }
151
152    /**
153     * Decrements this instance's value by 1; this method returns the value associated with the instance
154     * immediately after the decrement operation. This method is not thread safe.
155     *
156     * @return The value associated with the instance after it is decremented.
157     * @since 3.5
158     */
159    public float decrementAndGet() {
160        value--;
161        return value;
162    }
163
164    /**
165     * Returns the value of this MutableFloat as a double.
166     *
167     * @return The numeric value represented by this object after conversion to type double.
168     */
169    @Override
170    public double doubleValue() {
171        return value;
172    }
173
174    /**
175     * Compares this object against some other object. The result is {@code true} if and only if the argument is not {@code null} and is a {@link Float} object
176     * that represents a {@code float} that has the identical bit pattern to the bit pattern of the {@code float} represented by this object. For this purpose,
177     * 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
178     * each.
179     * <p>
180     * Note that in most cases, for two instances of class {@link Float},{@code f1} and {@code f2}, the value of {@code f1.equals(f2)} is {@code true} if and
181     * only if:
182     * </p>
183     * <pre>
184     * f1.floatValue() == f2.floatValue()
185     * </pre>
186     * <p>
187     * also has the value {@code true}. However, there are two exceptions:
188     * </p>
189     * <ul>
190     * <li>If {@code f1} and {@code f2} both represent {@code Float.NaN}, then the {@code equals} method returns {@code true}, even though
191     * {@code Float.NaN == Float.NaN} has the value {@code false}.</li>
192     * <li>If {@code f1} represents {@code +0.0f} while {@code f2} represents {@code -0.0f}, or vice versa, the {@code equal} test has the value {@code false},
193     * even though {@code 0.0f == -0.0f} has the value {@code true}.</li>
194     * </ul>
195     * <p>
196     * This definition allows hashtables to operate properly.
197     * </p>
198     *
199     * @param obj The object to compare with, null returns false.
200     * @return {@code true} if the objects are the same; {@code false} otherwise.
201     * @see Float#floatToIntBits(float)
202     */
203    @Override
204    public boolean equals(final Object obj) {
205        return obj instanceof MutableFloat
206            && Float.floatToIntBits(((MutableFloat) obj).value) == Float.floatToIntBits(value);
207    }
208
209    /**
210     * Returns the value of this MutableFloat as a float.
211     *
212     * @return The numeric value represented by this object after conversion to type float.
213     */
214    @Override
215    public float floatValue() {
216        return value;
217    }
218
219    /**
220     * Gets this instance's current value, then adds {@code operand}. This method is not thread-safe.
221     *
222     * @param operand The quantity to add, not null.
223     * @return The value associated with this instance immediately before the operand was added.
224     * @since 3.5
225     */
226    public float getAndAdd(final float operand) {
227        final float last = value;
228        this.value += operand;
229        return last;
230    }
231
232    /**
233     * Gets this instance's current value, then adds {@code operand}. This method is not thread-safe.
234     *
235     * @param operand The quantity to add, not null.
236     * @throws NullPointerException Thrown if {@code operand} is null.
237     * @return The value associated with this instance immediately before the operand was added.
238     * @since 3.5
239     */
240    public float getAndAdd(final Number operand) {
241        final float last = value;
242        this.value += operand.floatValue();
243        return last;
244    }
245
246    /**
247     * Gets this instance's current value, then decrements it by 1. This method is not thread-safe.
248     *
249     * @return The value associated with the instance before it was decremented.
250     * @since 3.5
251     */
252    public float getAndDecrement() {
253        final float last = value;
254        value--;
255        return last;
256    }
257
258    /**
259     * Gets this instance's current value, then increments it by 1. This method is not thread-safe.
260     *
261     * @return The value associated with the instance before it was incremented.
262     * @since 3.5
263     */
264    public float getAndIncrement() {
265        final float last = value;
266        value++;
267        return last;
268    }
269
270    /**
271     * Gets the value as a Float instance.
272     *
273     * @return The value as a Float, never null.
274     * @deprecated Use {@link #get()}.
275     */
276    @Deprecated
277    @Override
278    public Float getValue() {
279        return Float.valueOf(this.value);
280    }
281
282    /**
283     * Returns a suitable hash code for this mutable.
284     *
285     * @return A suitable hash code.
286     */
287    @Override
288    public int hashCode() {
289        return Float.floatToIntBits(value);
290    }
291
292    /**
293     * Increments the value.
294     *
295     * @since 2.2
296     */
297    public void increment() {
298        value++;
299    }
300
301    /**
302     * Increments this instance's value by 1; this method returns the value associated with the instance
303     * immediately after the increment operation. This method is not thread safe.
304     *
305     * @return The value associated with the instance after it is incremented.
306     * @since 3.5
307     */
308    public float incrementAndGet() {
309        value++;
310        return value;
311    }
312
313    // shortValue and byteValue rely on Number implementation
314    /**
315     * Returns the value of this MutableFloat as an int.
316     *
317     * @return The numeric value represented by this object after conversion to type int.
318     */
319    @Override
320    public int intValue() {
321        return (int) value;
322    }
323
324    /**
325     * Tests whether the float value is infinite.
326     *
327     * @return true if infinite
328     */
329    public boolean isInfinite() {
330        return Float.isInfinite(value);
331    }
332
333    /**
334     * Tests whether the float value is the special NaN value.
335     *
336     * @return true if NaN.
337     */
338    public boolean isNaN() {
339        return Float.isNaN(value);
340    }
341
342    /**
343     * Returns the value of this MutableFloat as a long.
344     *
345     * @return The numeric value represented by this object after conversion to type long.
346     */
347    @Override
348    public long longValue() {
349        return (long) value;
350    }
351
352    /**
353     * Sets the value.
354     *
355     * @param value  The value to set.
356     */
357    public void setValue(final float value) {
358        this.value = value;
359    }
360
361    /**
362     * Sets the value from any Number instance.
363     *
364     * @param value  The value to set, not null.
365     * @throws NullPointerException Thrown if the object is null.
366     */
367    @Override
368    public void setValue(final Number value) {
369        this.value = value.floatValue();
370    }
371
372    /**
373     * Subtracts a value from the value of this instance.
374     *
375     * @param operand  The value to subtract.
376     * @since 2.2
377     */
378    public void subtract(final float operand) {
379        this.value -= operand;
380    }
381
382    /**
383     * Subtracts a value from the value of this instance.
384     *
385     * @param operand  The value to subtract, not null.
386     * @throws NullPointerException Thrown if the object is null.
387     * @since 2.2
388     */
389    public void subtract(final Number operand) {
390        this.value -= operand.floatValue();
391    }
392
393    /**
394     * Gets this mutable as an instance of Float.
395     *
396     * @return A Float instance containing the value from this mutable, never null.
397     */
398    public Float toFloat() {
399        return Float.valueOf(floatValue());
400    }
401
402    /**
403     * Returns the String value of this mutable.
404     *
405     * @return The mutable value as a string.
406     */
407    @Override
408    public String toString() {
409        return String.valueOf(value);
410    }
411
412}