1 /* 2 * Licensed to the Apache Software Foundation (ASF) under one or more 3 * contributor license agreements. See the NOTICE file distributed with 4 * this work for additional information regarding copyright ownership. 5 * The ASF licenses this file to You under the Apache License, Version 2.0 6 * (the "License"); you may not use this file except in compliance with 7 * the License. You may obtain a copy of the License at 8 * 9 * http://www.apache.org/licenses/LICENSE-2.0 10 * 11 * Unless required by applicable law or agreed to in writing, software 12 * distributed under the License is distributed on an "AS IS" BASIS, 13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 14 * See the License for the specific language governing permissions and 15 * limitations under the License. 16 */ 17 18 package java.lang; 19 20 /** 21 * The wrapper for the primitive type {@code short}. 22 * 23 * @see java.lang.Number 24 * @since 1.1 25 */ 26 @FindBugsSuppressWarnings("DM_NUMBER_CTOR") 27 public final class Short extends Number implements Comparable<Short> { 28 29 private static final long serialVersionUID = 7515723908773894738L; 30 31 /** 32 * The value which the receiver represents. 33 */ 34 private final short value; 35 36 /** 37 * Constant for the maximum {@code short} value, 2<sup>15</sup>-1. 38 */ 39 public static final short MAX_VALUE = (short) 0x7FFF; 40 41 /** 42 * Constant for the minimum {@code short} value, -2<sup>15</sup>. 43 */ 44 public static final short MIN_VALUE = (short) 0x8000; 45 46 /** 47 * Constant for the number of bits needed to represent a {@code short} in 48 * two's complement form. 49 * 50 * @since 1.5 51 */ 52 public static final int SIZE = 16; 53 54 /** 55 * The {@link Class} object that represents the primitive type {@code 56 * short}. 57 */ 58 @SuppressWarnings("unchecked") 59 public static final Class<Short> TYPE 60 = (Class<Short>) short[].class.getComponentType(); 61 // Note: Short.TYPE can't be set to "short.class", since *that* is 62 // defined to be "java.lang.Short.TYPE"; 63 64 /** 65 * Constructs a new {@code Short} from the specified string. 66 * 67 * @param string 68 * the string representation of a short value. 69 * @throws NumberFormatException 70 * if {@code string} cannot be parsed as a short value. 71 * @see #parseShort(String) 72 */ 73 public Short(String string) throws NumberFormatException { 74 this(parseShort(string)); 75 } 76 77 /** 78 * Constructs a new {@code Short} with the specified primitive short value. 79 * 80 * @param value 81 * the primitive short value to store in the new instance. 82 */ 83 public Short(short value) { 84 this.value = value; 85 } 86 87 @Override 88 public byte byteValue() { 89 return (byte) value; 90 } 91 92 /** 93 * Compares this object to the specified short object to determine their 94 * relative order. 95 * 96 * @param object 97 * the short object to compare this object to. 98 * @return a negative value if the value of this short is less than the 99 * value of {@code object}; 0 if the value of this short and the 100 * value of {@code object} are equal; a positive value if the value 101 * of this short is greater than the value of {@code object}. 102 * @throws NullPointerException 103 * if {@code object} is null. 104 * @see java.lang.Comparable 105 * @since 1.2 106 */ 107 public int compareTo(Short object) { 108 return compare(value, object.value); 109 } 110 111 /** 112 * Compares two {@code short} values. 113 * @return 0 if lhs = rhs, less than 0 if lhs < rhs, and greater than 0 if lhs > rhs. 114 * @since 1.7 115 */ 116 public static int compare(short lhs, short rhs) { 117 return lhs > rhs ? 1 : (lhs < rhs ? -1 : 0); 118 } 119 120 /** 121 * Parses the specified string and returns a {@code Short} instance if the 122 * string can be decoded into a short value. The string may be an optional 123 * minus sign "-" followed by a hexadecimal ("0x..." or "#..."), octal 124 * ("0..."), or decimal ("...") representation of a short. 125 * 126 * @param string 127 * a string representation of a short value. 128 * @return a {@code Short} containing the value represented by 129 * {@code string}. 130 * @throws NumberFormatException 131 * if {@code string} cannot be parsed as a short value. 132 */ 133 public static Short decode(String string) throws NumberFormatException { 134 int intValue = Integer.decode(string).intValue(); 135 short result = (short) intValue; 136 if (result == intValue) { 137 return valueOf(result); 138 } 139 throw new NumberFormatException("Value out of range for short: \"" + string + "\""); 140 } 141 142 @Override 143 public double doubleValue() { 144 return value; 145 } 146 147 /** 148 * Compares this instance with the specified object and indicates if they 149 * are equal. In order to be equal, {@code object} must be an instance of 150 * {@code Short} and have the same short value as this object. 151 * 152 * @param object 153 * the object to compare this short with. 154 * @return {@code true} if the specified object is equal to this 155 * {@code Short}; {@code false} otherwise. 156 */ 157 @Override 158 public boolean equals(Object object) { 159 return (object instanceof Short) && (((Short) object).value == value); 160 } 161 162 @Override 163 public float floatValue() { 164 return value; 165 } 166 167 @Override 168 public int hashCode() { 169 return value; 170 } 171 172 @Override 173 public int intValue() { 174 return value; 175 } 176 177 @Override 178 public long longValue() { 179 return value; 180 } 181 182 /** 183 * Parses the specified string as a signed decimal short value. The ASCII 184 * character \u002d ('-') is recognized as the minus sign. 185 * 186 * @param string 187 * the string representation of a short value. 188 * @return the primitive short value represented by {@code string}. 189 * @throws NumberFormatException 190 * if {@code string} cannot be parsed as a short value. 191 */ 192 public static short parseShort(String string) throws NumberFormatException { 193 return parseShort(string, 10); 194 } 195 196 /** 197 * Parses the specified string as a signed short value using the specified 198 * radix. The ASCII character \u002d ('-') is recognized as the minus sign. 199 * 200 * @param string 201 * the string representation of a short value. 202 * @param radix 203 * the radix to use when parsing. 204 * @return the primitive short value represented by {@code string} using 205 * {@code radix}. 206 * @throws NumberFormatException 207 * if {@code string} cannot be parsed as a short value, or 208 * {@code radix < Character.MIN_RADIX || 209 * radix > Character.MAX_RADIX}. 210 */ 211 public static short parseShort(String string, int radix) throws NumberFormatException { 212 int intValue = Integer.parseInt(string, radix); 213 short result = (short) intValue; 214 if (result == intValue) { 215 return result; 216 } 217 throw new NumberFormatException("Value out of range for short: \"" + string + "\""); 218 } 219 220 /** 221 * Gets the primitive value of this short. 222 * 223 * @return this object's primitive value. 224 */ 225 @Override 226 public short shortValue() { 227 return value; 228 } 229 230 @Override 231 public String toString() { 232 return Integer.toString(value); 233 } 234 235 /** 236 * Returns a string containing a concise, human-readable description of the 237 * specified short value with radix 10. 238 * 239 * @param value 240 * the short to convert to a string. 241 * @return a printable representation of {@code value}. 242 */ 243 public static String toString(short value) { 244 return Integer.toString(value); 245 } 246 247 /** 248 * Parses the specified string as a signed decimal short value. 249 * 250 * @param string 251 * the string representation of a short value. 252 * @return a {@code Short} instance containing the short value represented 253 * by {@code string}. 254 * @throws NumberFormatException 255 * if {@code string} cannot be parsed as a short value. 256 * @see #parseShort(String) 257 */ 258 public static Short valueOf(String string) throws NumberFormatException { 259 return valueOf(parseShort(string)); 260 } 261 262 /** 263 * Parses the specified string as a signed short value using the specified 264 * radix. 265 * 266 * @param string 267 * the string representation of a short value. 268 * @param radix 269 * the radix to use when parsing. 270 * @return a {@code Short} instance containing the short value represented 271 * by {@code string} using {@code radix}. 272 * @throws NumberFormatException 273 * if {@code string} cannot be parsed as a short value, or 274 * {@code radix < Character.MIN_RADIX || 275 * radix > Character.MAX_RADIX}. 276 * @see #parseShort(String, int) 277 */ 278 public static Short valueOf(String string, int radix) throws NumberFormatException { 279 return valueOf(parseShort(string, radix)); 280 } 281 282 /** 283 * Reverses the bytes of the specified short. 284 * 285 * @param s 286 * the short value for which to reverse bytes. 287 * @return the reversed value. 288 * @since 1.5 289 */ 290 public static short reverseBytes(short s) { 291 return (short) ((s << 8) | ((s >>> 8) & 0xFF)); 292 } 293 294 /** 295 * Returns a {@code Short} instance for the specified short value. 296 * <p> 297 * If it is not necessary to get a new {@code Short} instance, it is 298 * recommended to use this method instead of the constructor, since it 299 * maintains a cache of instances which may result in better performance. 300 * 301 * @param s 302 * the short value to store in the instance. 303 * @return a {@code Short} instance containing {@code s}. 304 * @since 1.5 305 */ 306 public static Short valueOf(short s) { 307 return s < -128 || s >= 128 ? new Short(s) : SMALL_VALUES[s + 128]; 308 } 309 310 /** 311 * A cache of instances used by {@link Short#valueOf(short)} and auto-boxing. 312 */ 313 private static final Short[] SMALL_VALUES = new Short[256]; 314 315 static { 316 for (int i = -128; i < 128; i++) { 317 SMALL_VALUES[i + 128] = new Short((short) i); 318 } 319 } 320 } 321
