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Diffstat (limited to 'libjava/classpath/java/lang/Short.java')
| -rw-r--r-- | libjava/classpath/java/lang/Short.java | 383 |
1 files changed, 383 insertions, 0 deletions
diff --git a/libjava/classpath/java/lang/Short.java b/libjava/classpath/java/lang/Short.java new file mode 100644 index 000000000..ec87f933e --- /dev/null +++ b/libjava/classpath/java/lang/Short.java @@ -0,0 +1,383 @@ +/* Short.java -- object wrapper for short + Copyright (C) 1998, 2001, 2002, 2004, 2005 Free Software Foundation, Inc. + +This file is part of GNU Classpath. + +GNU Classpath is free software; you can redistribute it and/or modify +it under the terms of the GNU General Public License as published by +the Free Software Foundation; either version 2, or (at your option) +any later version. + +GNU Classpath is distributed in the hope that it will be useful, but +WITHOUT ANY WARRANTY; without even the implied warranty of +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU +General Public License for more details. + +You should have received a copy of the GNU General Public License +along with GNU Classpath; see the file COPYING. If not, write to the +Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA +02110-1301 USA. + +Linking this library statically or dynamically with other modules is +making a combined work based on this library. Thus, the terms and +conditions of the GNU General Public License cover the whole +combination. + +As a special exception, the copyright holders of this library give you +permission to link this library with independent modules to produce an +executable, regardless of the license terms of these independent +modules, and to copy and distribute the resulting executable under +terms of your choice, provided that you also meet, for each linked +independent module, the terms and conditions of the license of that +module. An independent module is a module which is not derived from +or based on this library. If you modify this library, you may extend +this exception to your version of the library, but you are not +obligated to do so. If you do not wish to do so, delete this +exception statement from your version. */ + + +package java.lang; + +/** + * Instances of class <code>Short</code> represent primitive + * <code>short</code> values. + * + * Additionally, this class provides various helper functions and variables + * related to shorts. + * + * @author Paul Fisher + * @author John Keiser + * @author Eric Blake (ebb9@email.byu.edu) + * @author Tom Tromey (tromey@redhat.com) + * @author Andrew John Hughes (gnu_andrew@member.fsf.org) + * @since 1.1 + * @status updated to 1.5 + */ +public final class Short extends Number implements Comparable<Short> +{ + /** + * Compatible with JDK 1.1+. + */ + private static final long serialVersionUID = 7515723908773894738L; + + /** + * The minimum value a <code>short</code> can represent is -32768 (or + * -2<sup>15</sup>). + */ + public static final short MIN_VALUE = -32768; + + /** + * The minimum value a <code>short</code> can represent is 32767 (or + * 2<sup>15</sup>). + */ + public static final short MAX_VALUE = 32767; + + /** + * The primitive type <code>short</code> is represented by this + * <code>Class</code> object. + */ + public static final Class<Short> TYPE = (Class<Short>) VMClassLoader.getPrimitiveClass('S'); + + /** + * The number of bits needed to represent a <code>short</code>. + * @since 1.5 + */ + public static final int SIZE = 16; + + // This caches some Short values, and is used by boxing conversions + // via valueOf(). We must cache at least -128..127; these constants + // control how much we actually cache. + private static final int MIN_CACHE = -128; + private static final int MAX_CACHE = 127; + private static Short[] shortCache = new Short[MAX_CACHE - MIN_CACHE + 1]; + static + { + for (short i=MIN_CACHE; i <= MAX_CACHE; i++) + shortCache[i - MIN_CACHE] = new Short(i); + } + + /** + * The immutable value of this Short. + * + * @serial the wrapped short + */ + private final short value; + + /** + * Create a <code>Short</code> object representing the value of the + * <code>short</code> argument. + * + * @param value the value to use + */ + public Short(short value) + { + this.value = value; + } + + /** + * Create a <code>Short</code> object representing the value of the + * argument after conversion to a <code>short</code>. + * + * @param s the string to convert + * @throws NumberFormatException if the String cannot be parsed + */ + public Short(String s) + { + value = parseShort(s, 10); + } + + /** + * Converts the <code>short</code> to a <code>String</code> and assumes + * a radix of 10. + * + * @param s the <code>short</code> to convert to <code>String</code> + * @return the <code>String</code> representation of the argument + */ + public static String toString(short s) + { + return String.valueOf(s); + } + + /** + * Converts the specified <code>String</code> into a <code>short</code>. + * This function assumes a radix of 10. + * + * @param s the <code>String</code> to convert + * @return the <code>short</code> value of <code>s</code> + * @throws NumberFormatException if <code>s</code> cannot be parsed as a + * <code>short</code> + */ + public static short parseShort(String s) + { + return parseShort(s, 10); + } + + /** + * Converts the specified <code>String</code> into a <code>short</code> + * using the specified radix (base). The string must not be <code>null</code> + * or empty. It may begin with an optional '-', which will negate the answer, + * provided that there are also valid digits. Each digit is parsed as if by + * <code>Character.digit(d, radix)</code>, and must be in the range + * <code>0</code> to <code>radix - 1</code>. Finally, the result must be + * within <code>MIN_VALUE</code> to <code>MAX_VALUE</code>, inclusive. + * Unlike Double.parseDouble, you may not have a leading '+'. + * + * @param s the <code>String</code> to convert + * @param radix the radix (base) to use in the conversion + * @return the <code>String</code> argument converted to <code>short</code> + * @throws NumberFormatException if <code>s</code> cannot be parsed as a + * <code>short</code> + */ + public static short parseShort(String s, int radix) + { + int i = Integer.parseInt(s, radix, false); + if ((short) i != i) + throw new NumberFormatException(); + return (short) i; + } + + /** + * Creates a new <code>Short</code> object using the <code>String</code> + * and specified radix (base). + * + * @param s the <code>String</code> to convert + * @param radix the radix (base) to convert with + * @return the new <code>Short</code> + * @throws NumberFormatException if <code>s</code> cannot be parsed as a + * <code>short</code> + * @see #parseShort(String, int) + */ + public static Short valueOf(String s, int radix) + { + return valueOf(parseShort(s, radix)); + } + + /** + * Creates a new <code>Short</code> object using the <code>String</code>, + * assuming a radix of 10. + * + * @param s the <code>String</code> to convert + * @return the new <code>Short</code> + * @throws NumberFormatException if <code>s</code> cannot be parsed as a + * <code>short</code> + * @see #Short(String) + * @see #parseShort(String) + */ + public static Short valueOf(String s) + { + return valueOf(parseShort(s, 10)); + } + + /** + * Returns a <code>Short</code> object wrapping the value. + * In contrast to the <code>Short</code> constructor, this method + * will cache some values. It is used by boxing conversion. + * + * @param val the value to wrap + * @return the <code>Short</code> + * @since 1.5 + */ + public static Short valueOf(short val) + { + if (val < MIN_CACHE || val > MAX_CACHE) + return new Short(val); + else + return shortCache[val - MIN_CACHE]; + } + + /** + * Convert the specified <code>String</code> into a <code>Short</code>. + * The <code>String</code> may represent decimal, hexadecimal, or + * octal numbers. + * + * <p>The extended BNF grammar is as follows:<br> + * <pre> + * <em>DecodableString</em>: + * ( [ <code>-</code> ] <em>DecimalNumber</em> ) + * | ( [ <code>-</code> ] ( <code>0x</code> | <code>0X</code> + * | <code>#</code> ) <em>HexDigit</em> { <em>HexDigit</em> } ) + * | ( [ <code>-</code> ] <code>0</code> { <em>OctalDigit</em> } ) + * <em>DecimalNumber</em>: + * <em>DecimalDigit except '0'</em> { <em>DecimalDigit</em> } + * <em>DecimalDigit</em>: + * <em>Character.digit(d, 10) has value 0 to 9</em> + * <em>OctalDigit</em>: + * <em>Character.digit(d, 8) has value 0 to 7</em> + * <em>DecimalDigit</em>: + * <em>Character.digit(d, 16) has value 0 to 15</em> + * </pre> + * Finally, the value must be in the range <code>MIN_VALUE</code> to + * <code>MAX_VALUE</code>, or an exception is thrown. + * + * @param s the <code>String</code> to interpret + * @return the value of the String as a <code>Short</code> + * @throws NumberFormatException if <code>s</code> cannot be parsed as a + * <code>short</code> + * @throws NullPointerException if <code>s</code> is null + * @see Integer#decode(String) + */ + public static Short decode(String s) + { + int i = Integer.parseInt(s, 10, true); + if ((short) i != i) + throw new NumberFormatException(); + return valueOf((short) i); + } + + /** + * Return the value of this <code>Short</code> as a <code>byte</code>. + * + * @return the byte value + */ + public byte byteValue() + { + return (byte) value; + } + + /** + * Return the value of this <code>Short</code>. + * + * @return the short value + */ + public short shortValue() + { + return value; + } + + /** + * Return the value of this <code>Short</code> as an <code>int</code>. + * + * @return the int value + */ + public int intValue() + { + return value; + } + + /** + * Return the value of this <code>Short</code> as a <code>long</code>. + * + * @return the long value + */ + public long longValue() + { + return value; + } + + /** + * Return the value of this <code>Short</code> as a <code>float</code>. + * + * @return the float value + */ + public float floatValue() + { + return value; + } + + /** + * Return the value of this <code>Short</code> as a <code>double</code>. + * + * @return the double value + */ + public double doubleValue() + { + return value; + } + + /** + * Converts the <code>Short</code> value to a <code>String</code> and + * assumes a radix of 10. + * + * @return the <code>String</code> representation of this <code>Short</code> + */ + public String toString() + { + return String.valueOf(value); + } + + /** + * Return a hashcode representing this Object. <code>Short</code>'s hash + * code is simply its value. + * + * @return this Object's hash code + */ + public int hashCode() + { + return value; + } + + /** + * Returns <code>true</code> if <code>obj</code> is an instance of + * <code>Short</code> and represents the same short value. + * + * @param obj the object to compare + * @return whether these Objects are semantically equal + */ + public boolean equals(Object obj) + { + return obj instanceof Short && value == ((Short) obj).value; + } + + /** + * Compare two Shorts numerically by comparing their <code>short</code> + * values. The result is positive if the first is greater, negative if the + * second is greater, and 0 if the two are equal. + * + * @param s the Short to compare + * @return the comparison + * @since 1.2 + */ + public int compareTo(Short s) + { + return value - s.value; + } + + /** + * Reverse the bytes in val. + * @since 1.5 + */ + public static short reverseBytes(short val) + { + return (short) (((val >> 8) & 0xff) | ((val << 8) & 0xff00)); + } +} |