/* * @(#)Short.java 1.43 04/05/11 * * Copyright 2004 Sun Microsystems, Inc. All rights reserved. * SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms. */ package java.lang; /** * The Short class wraps a value of primitive type * short in an object. An object of type * Short contains a single field whose type is * short. * *

* * In addition, this class provides several methods for converting a * short to a String and a * String to a short, as well as other * constants and methods useful when dealing with a short. * * @author Nakul Saraiya * @version 1.43, 05/11/04 * @see java.lang.Number * @since JDK1.1 */ public final class Short extends Number implements Comparable { /** * A constant holding the minimum value a short can * have, -215. */ public static final short MIN_VALUE = -32768; /** * A constant holding the maximum value a short can * have, 215-1. */ public static final short MAX_VALUE = 32767; /** * The Class instance representing the primitive type * short. */ public static final Class TYPE = (Class) Class.getPrimitiveClass("short"); /** * Returns a new String object representing the * specified short. The radix is assumed to be 10. * * @param s the short to be converted * @return the string representation of the specified short * @see java.lang.Integer#toString(int) */ public static String toString(short s) { return Integer.toString((int)s, 10); } /** * Parses the string argument as a signed decimal * short. The characters in the string must all be * decimal digits, except that the first character may be an ASCII * minus sign '-' ('\u002D') to * indicate a negative value. The resulting short value is * returned, exactly as if the argument and the radix 10 were * given as arguments to the {@link #parseShort(java.lang.String, * int)} method. * * @param s a String containing the short * representation to be parsed * @return the short value represented by the * argument in decimal. * @exception NumberFormatException If the string does not * contain a parsable short. */ public static short parseShort(String s) throws NumberFormatException { return parseShort(s, 10); } /** * Parses the string argument as a signed short in * the radix specified by the second argument. The characters in * the string must all be digits, of the specified radix (as * determined by whether {@link java.lang.Character#digit(char, * int)} returns a nonnegative value) except that the first * character may be an ASCII minus sign '-' * ('\u002D') to indicate a negative value. The * resulting byte value is returned. *

* An exception of type NumberFormatException is * thrown if any of the following situations occurs: *

* * @param s the String containing the * short representation to be parsed * @param radix the radix to be used while parsing s * @return the short represented by the string * argument in the specified radix. * @exception NumberFormatException If the String * does not contain a parsable short. */ public static short parseShort(String s, int radix) throws NumberFormatException { int i = Integer.parseInt(s, radix); if (i < MIN_VALUE || i > MAX_VALUE) throw new NumberFormatException( "Value out of range. Value:\"" + s + "\" Radix:" + radix); return (short)i; } /** * Returns a Short object holding the value * extracted from the specified String when parsed * with the radix given by the second argument. The first argument * is interpreted as representing a signed short in * the radix specified by the second argument, exactly as if the * argument were given to the {@link #parseShort(java.lang.String, * int)} method. The result is a Short object that * represents the short value specified by the string. *

In other words, this method returns a Short object * equal to the value of: * *

* new Short(Short.parseShort(s, radix)) *
* * @param s the string to be parsed * @param radix the radix to be used in interpreting s * @return a Short object holding the value * represented by the string argument in the * specified radix. * @exception NumberFormatException If the String does * not contain a parsable short. */ public static Short valueOf(String s, int radix) throws NumberFormatException { return new Short(parseShort(s, radix)); } /** * Returns a Short object holding the * value given by the specified String. The argument * is interpreted as representing a signed decimal * short, exactly as if the argument were given to * the {@link #parseShort(java.lang.String)} method. The result is * a Short object that represents the * short value specified by the string.

In other * words, this method returns a Byte object equal to * the value of: * *

* new Short(Short.parseShort(s)) *
* * @param s the string to be parsed * @return a Short object holding the value * represented by the string argument * @exception NumberFormatException If the String does * not contain a parsable short. */ public static Short valueOf(String s) throws NumberFormatException { return valueOf(s, 10); } private static class ShortCache { private ShortCache(){} static final Short cache[] = new Short[-(-128) + 127 + 1]; static { for(int i = 0; i < cache.length; i++) cache[i] = new Short((short)(i - 128)); } } /** * Returns a Short instance representing the specified * short value. * If a new Short instance is not required, this method * should generally be used in preference to the constructor * {@link #Short(short)}, as this method is likely to yield * significantly better space and time performance by caching * frequently requested values. * * @param s a short value. * @return a Short instance representing s. * @since 1.5 */ public static Short valueOf(short s) { final int offset = 128; int sAsInt = s; if (sAsInt >= -128 && sAsInt <= 127) { // must cache return ShortCache.cache[sAsInt + offset]; } return new Short(s); } /** * Decodes a String into a Short. * Accepts decimal, hexadecimal, and octal numbers given by * the following grammar: * *
*
*
DecodableString: *
Signopt DecimalNumeral *
Signopt 0x HexDigits *
Signopt 0X HexDigits *
Signopt # HexDigits *
Signopt 0 OctalDigits *

*

Sign: *
- *
*
* * DecimalNumeral, HexDigits, and OctalDigits * are defined in §3.10.1 * of the Java * Language Specification. *

* The sequence of characters following an (optional) negative * sign and/or radix specifier ("0x", * "0X", "#", or * leading zero) is parsed as by the Short.parseShort * method with the indicated radix (10, 16, or 8). This sequence * of characters must represent a positive value or a {@link * NumberFormatException} will be thrown. The result is negated * if first character of the specified String is the * minus sign. No whitespace characters are permitted in the * String. * * @param nm the String to decode. * @return a Short object holding the short * value represented by nm * @exception NumberFormatException if the String does not * contain a parsable short. * @see java.lang.Short#parseShort(java.lang.String, int) */ public static Short decode(String nm) throws NumberFormatException { int radix = 10; int index = 0; boolean negative = false; Short result; // Handle minus sign, if present if (nm.startsWith("-")) { negative = true; index++; } // Handle radix specifier, if present if (nm.startsWith("0x", index) || nm.startsWith("0X", index)) { index += 2; radix = 16; } else if (nm.startsWith("#", index)) { index ++; radix = 16; } else if (nm.startsWith("0", index) && nm.length() > 1 + index) { index ++; radix = 8; } if (nm.startsWith("-", index)) throw new NumberFormatException("Negative sign in wrong position"); try { result = Short.valueOf(nm.substring(index), radix); result = negative ? new Short((short)-result.shortValue()) :result; } catch (NumberFormatException e) { // If number is Short.MIN_VALUE, we'll end up here. The next line // handles this case, and causes any genuine format error to be // rethrown. String constant = negative ? new String("-" + nm.substring(index)) : nm.substring(index); result = Short.valueOf(constant, radix); } return result; } /** * The value of the Short. * * @serial */ private final short value; /** * Constructs a newly allocated Short object that * represents the specified short value. * * @param value the value to be represented by the * Short. */ public Short(short value) { this.value = value; } /** * Constructs a newly allocated Short object that * represents the short value indicated by the * String parameter. The string is converted to a * short value in exactly the manner used by the * parseShort method for radix 10. * * @param s the String to be converted to a * Short * @exception NumberFormatException If the String * does not contain a parsable short. * @see java.lang.Short#parseShort(java.lang.String, int) */ public Short(String s) throws NumberFormatException { this.value = parseShort(s, 10); } /** * Returns the value of this Short as a * byte. */ public byte byteValue() { return (byte)value; } /** * Returns the value of this Short as a * short. */ public short shortValue() { return value; } /** * Returns the value of this Short as an * int. */ public int intValue() { return (int)value; } /** * Returns the value of this Short as a * long. */ public long longValue() { return (long)value; } /** * Returns the value of this Short as a * float. */ public float floatValue() { return (float)value; } /** * Returns the value of this Short as a * double. */ public double doubleValue() { return (double)value; } /** * Returns a String object representing this * Short's value. The value is converted to signed * decimal representation and returned as a string, exactly as if * the short value were given as an argument to the * {@link java.lang.Short#toString(short)} method. * * @return a string representation of the value of this object in * base 10. */ public String toString() { return String.valueOf((int)value); } /** * Returns a hash code for this Short. */ public int hashCode() { return (int)value; } /** * Compares this object to the specified object. The result is * true if and only if the argument is not * null and is a Short object that * contains the same short value as this object. * * @param obj the object to compare with * @return true if the objects are the same; * false otherwise. */ public boolean equals(Object obj) { if (obj instanceof Short) { return value == ((Short)obj).shortValue(); } return false; } /** * Compares two Short objects numerically. * * @param anotherShort the Short to be compared. * @return the value 0 if this Short is * equal to the argument Short; a value less than * 0 if this Short is numerically less * than the argument Short; and a value greater than * 0 if this Short is numerically * greater than the argument Short (signed * comparison). * @since 1.2 */ public int compareTo(Short anotherShort) { return this.value - anotherShort.value; } /** * The number of bits used to represent a short value in two's * complement binary form. */ public static final int SIZE = 16; /** * Returns the value obtained by reversing the order of the bytes in the * two's complement representation of the specified short value. * * @return the value obtained by reversing (or, equivalently, swapping) * the bytes in the specified short value. * @since 1.5 */ public static short reverseBytes(short i) { return (short) (((i & 0xFF00) >> 8) | (i << 8)); } /** use serialVersionUID from JDK 1.1. for interoperability */ private static final long serialVersionUID = 7515723908773894738L; }