MuFloat


1   /***************************************
2    *                                     *
3    *  JBoss: The OpenSource J2EE WebOS   *
4    *                                     *
5    *  Distributable under LGPL license.  *
6    *  See terms of license at gnu.org.   *
7    *                                     *
8    ***************************************/
9   
10  package org.jboss.util;
11  
12  /**
13   * A mutable float class.
14   *
15   * @version <tt>$Revision: 1.1 $</tt>
16   * @author  <a HREF="mailto:jason@planet57.com">Jason Dillon</a>
17   */
18  public class MuFloat
19     extends MuNumber
20  {
21     /** Float value */
22     private float value; // = 0;
23  
24     /**
25      * Construct a new mutable float.
26      */
27     public MuFloat() {}
28  
29     /**
30      * Construct a new mutable float.
31      *
32      * @param f    <code>float</code> value.
33      */
34     public MuFloat(float f) {
35        value = f;
36     }
37  
38     /**
39      * Construct a new mutable float.
40      *
41      * @param obj     Object to convert to a <code>float</code> value.
42      */
43     public MuFloat(Object   obj) {
44        setValue(obj);
45     }
46  
47     /**
48      * Set the value.
49      *
50      * @param f    <code>float</code> value.
51      * @return     The previous value.
52      */
53     public float set(float f) {
54        float old = value;
55        value = f;
56        return old;
57     }
58  
59     /**
60      * Get the current value.
61      *
62      * @return  The current value.
63      */
64     public float get() {
65        return value;
66     }
67  
68     /**
69      * Set the value to value only if the current value is equal to 
70      * the assumed value.
71      *
72      * @param assumed  The assumed value.
73      * @param b        The new value.
74      * @return         True if value was changed.
75      */
76     public boolean commit(float assumed, float b) {
77        boolean success = Primitives.equals(assumed, value);
78        if (success) value = b;
79        return success;
80     }
81  
82     /**
83      * Swap values with another mutable float.
84      *
85      * @param b       Mutable float to swap values with.
86      * @return        The new value.
87      */
88     public float swap(MuFloat b) {
89        if (b == this) return value;
90  
91        float temp = value;
92        value = b.value;
93        b.value = temp;
94  
95        return value;
96     }
97  
98     /**
99      * Add the specified amount.
100     *
101     * @param amount  Amount to add.
102     * @return        The new value.
103     */
104    public float add(float amount) {
105       return value += amount;
106    }
107 
108    /**
109     * Subtract the specified amount.
110     *
111     * @param amount  Amount to subtract.
112     * @return        The new value.
113     */
114    public float subtract(float amount) {
115       return value -= amount;
116    }
117 
118    /**
119     * Multiply by the specified factor.
120     *
121     * @param factor  Factor to multiply by.
122     * @return        The new value.
123     */
124    public float multiply(float factor) {
125       return value *= factor;
126    }
127 
128    /**
129     * Divide by the specified factor.
130     *
131     * @param factor  Factor to divide by.
132     * @return        The new value.
133     */
134    public float divide(float factor) {
135       return value /= factor;
136    }
137 
138    /**
139     * Set the value to the negative of its current value.
140     *
141     * @return     The new value.
142     */
143    public float negate() {
144       value = ((float)-value);
145       return value;
146    }
147 
148    /**
149     * Compares this object with the specified float for order.
150     *
151     * @param other   Value to compare with.
152     * @return        A negative integer, zero, or a positive integer as
153     *                this object is less than, equal to, or greater than
154     *                the specified object.
155     */
156    public int compareTo(float other) {
157       return (value < other) ? -1 : Primitives.equals(value, other) ? 0 : 1;
158    }
159 
160    /**
161     * Compares this object with the specified object for order.
162     *
163     * @param other   Value to compare with.
164     * @return        A negative integer, zero, or a positive integer as
165     *                this object is less than, equal to, or greater than
166     *                the specified object.
167     *
168     * @throws ClassCastException    Object is not a MuFloat.
169     */
170    public int compareTo(Object   obj) {
171       return compareTo((MuFloat)obj);
172    }
173 
174    /**
175     * Convert this mutable float to a string.
176     *
177     * @return   String value.
178     */
179    public String   toString() {
180       return String.valueOf(value);
181    }
182 
183    /**
184     * Get the hash code for this mutable float.
185     *
186     * @return   Hash code.
187     */
188    public int hashCode() {
189       return HashCode.generate(value);
190    }
191 
192    /**
193     * Test the equality of this mutable double with another object.
194     *
195     * @param obj    Object to test equality with.
196     * @return       True if object is equal.
197     */
198    public boolean equals(Object   obj) {
199       if (obj == this) return true;
200 
201       if (obj != null && obj.getClass() == getClass()) {
202          return Primitives.equals(value, ((MuFloat)obj).floatValue());
203       }
204 
205       return false;
206    }
207 
208    /**
209     * Return a cloned copy of this mutable float.
210     *
211     * @return   Cloaned mutable float.
212     */
213    public Object   clone() {
214       try {
215          return super.clone();
216       }
217       catch (CloneNotSupportedException   e) {
218          throw new InternalError  ();
219       }
220    }
221 
222 
223    /////////////////////////////////////////////////////////////////////////
224    //                             Number Support                          //
225    /////////////////////////////////////////////////////////////////////////
226 
227    /**
228     * Return the <code>byte</code> value of this object.
229     *
230     * @return   <code>byte</code> value.
231     */
232    public byte byteValue() {
233       return (byte)value;
234    }
235 
236    /**
237     * Return the <code>short</code> value of this object.
238     *
239     * @return   <code>short</code> value.
240     */
241    public short shortValue() {
242       return (short)value;
243    }
244 
245    /**
246     * Return the <code>int</code> value of this object.
247     *
248     * @return   <code>int</code> value.
249     */
250    public int intValue() {
251       return (int)value;
252    }
253 
254    /**
255     * Return the <code>long</code> value of this object.
256     *
257     * @return   <code>long</code> value.
258     */
259    public long longValue() {
260       return (long)value;
261    }
262 
263    /**
264     * Return the <code>float</code> value of this object.
265     *
266     * @return   <code>float</code> value.
267     */
268    public float floatValue() {
269       return (float)value;
270    }
271 
272    /**
273     * Return the <code>double</code> value of this object.
274     *
275     * @return   <code>double</code> value.
276     */
277    public double doubleValue() {
278       return (double)value;
279    }
280 
281 
282    /////////////////////////////////////////////////////////////////////////
283    //                            Mutable Support                          //
284    /////////////////////////////////////////////////////////////////////////
285 
286    /**
287     * Set the value of this mutable float.
288     *
289     * @param obj  Object to convert to a <code>float</code> value.
290     *
291     * @throws NotCoercibleException    Can not convert to <code>float</code>.
292     */
293    public void setValue(Object   obj) {
294       if (obj instanceof Number  ) {
295          value = ((Number  )obj).floatValue();
296       }
297       else if (obj instanceof String  ) {
298          try {
299             value = Float.parseFloat(String.valueOf(obj));
300          }
301          catch (Exception   e) {
302             throw new NotCoercibleException("can not convert to 'float': " + obj);
303          }
304       }
305       else {
306          throw new NotCoercibleException("can not convert to 'float': " + obj);
307       }
308    }
309 
310    /**
311     * Get the float value of this mutable float.
312     *
313     * @return   <code>java.lang.Float</code> value.
314     */
315    public Object   getValue() {
316       return new Float  (value);
317    }
318 }
319
A to Z: JavaDoc & Examples Daily Java News & Articles Open Source Projects Open Source Codes Free Computer Books Remove Frame
Popular Tags