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Diffstat (limited to 'libjava/classpath/java/lang/Integer.java')
| -rw-r--r-- | libjava/classpath/java/lang/Integer.java | 858 |
1 files changed, 0 insertions, 858 deletions
diff --git a/libjava/classpath/java/lang/Integer.java b/libjava/classpath/java/lang/Integer.java deleted file mode 100644 index 25eb5d5..0000000 --- a/libjava/classpath/java/lang/Integer.java +++ /dev/null @@ -1,858 +0,0 @@ -/* Integer.java -- object wrapper for int - Copyright (C) 1998, 1999, 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>Integer</code> represent primitive - * <code>int</code> values. - * - * Additionally, this class provides various helper functions and variables - * related to ints. - * - * @author Paul Fisher - * @author John Keiser - * @author Warren Levy - * @author Eric Blake (ebb9@email.byu.edu) - * @author Tom Tromey (tromey@redhat.com) - * @author Andrew John Hughes (gnu_andrew@member.fsf.org) - * @author Ian Rogers - * @since 1.0 - * @status updated to 1.5 - */ -public final class Integer extends Number implements Comparable<Integer> -{ - /** - * Compatible with JDK 1.0.2+. - */ - private static final long serialVersionUID = 1360826667806852920L; - - /** - * The minimum value an <code>int</code> can represent is -2147483648 (or - * -2<sup>31</sup>). - */ - public static final int MIN_VALUE = 0x80000000; - - /** - * The maximum value an <code>int</code> can represent is 2147483647 (or - * 2<sup>31</sup> - 1). - */ - public static final int MAX_VALUE = 0x7fffffff; - - /** - * The primitive type <code>int</code> is represented by this - * <code>Class</code> object. - * @since 1.1 - */ - public static final Class<Integer> TYPE = (Class<Integer>) VMClassLoader.getPrimitiveClass('I'); - - /** - * The number of bits needed to represent an <code>int</code>. - * @since 1.5 - */ - public static final int SIZE = 32; - - // This caches some Integer 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 final Integer[] intCache = new Integer[MAX_CACHE - MIN_CACHE + 1]; - static - { - for (int i=MIN_CACHE; i <= MAX_CACHE; i++) - intCache[i - MIN_CACHE] = new Integer(i); - } - - /** - * The immutable value of this Integer. - * - * @serial the wrapped int - */ - private final int value; - - /** - * Create an <code>Integer</code> object representing the value of the - * <code>int</code> argument. - * - * @param value the value to use - */ - public Integer(int value) - { - this.value = value; - } - - /** - * Create an <code>Integer</code> object representing the value of the - * argument after conversion to an <code>int</code>. - * - * @param s the string to convert - * @throws NumberFormatException if the String does not contain an int - * @see #valueOf(String) - */ - public Integer(String s) - { - value = parseInt(s, 10, false); - } - - /** - * Return the size of a string large enough to hold the given number - * - * @param num the number we want the string length for (must be positive) - * @param radix the radix (base) that will be used for the string - * @return a size sufficient for a string of num - */ - private static int stringSize(int num, int radix) { - int exp; - if (radix < 4) - { - exp = 1; - } - else if (radix < 8) - { - exp = 2; - } - else if (radix < 16) - { - exp = 3; - } - else if (radix < 32) - { - exp = 4; - } - else - { - exp = 5; - } - int size=0; - do - { - num >>>= exp; - size++; - } - while(num != 0); - return size; - } - - /** - * Converts the <code>int</code> to a <code>String</code> using - * the specified radix (base). If the radix exceeds - * <code>Character.MIN_RADIX</code> or <code>Character.MAX_RADIX</code>, 10 - * is used instead. If the result is negative, the leading character is - * '-' ('\\u002D'). The remaining characters come from - * <code>Character.forDigit(digit, radix)</code> ('0'-'9','a'-'z'). - * - * @param num the <code>int</code> to convert to <code>String</code> - * @param radix the radix (base) to use in the conversion - * @return the <code>String</code> representation of the argument - */ - public static String toString(int num, int radix) - { - if (radix < Character.MIN_RADIX || radix > Character.MAX_RADIX) - radix = 10; - - // Is the value negative? - boolean isNeg = num < 0; - - // Is the string a single character? - if (!isNeg && num < radix) - return new String(digits, num, 1, true); - - // Compute string size and allocate buffer - // account for a leading '-' if the value is negative - int size; - int i; - char[] buffer; - if (isNeg) - { - num = -num; - - // When the value is MIN_VALUE, it overflows when made positive - if (num < 0) - { - i = size = stringSize(MAX_VALUE, radix) + 2; - buffer = new char[size]; - buffer[--i] = digits[(int) (-(num + radix) % radix)]; - num = -(num / radix); - } - else - { - i = size = stringSize(num, radix) + 1; - buffer = new char[size]; - } - } - else - { - i = size = stringSize(num, radix); - buffer = new char[size]; - } - - do - { - buffer[--i] = digits[num % radix]; - num /= radix; - } - while (num > 0); - - if (isNeg) - buffer[--i] = '-'; - - // Package constructor avoids an array copy. - return new String(buffer, i, size - i, true); - } - - /** - * Converts the <code>int</code> to a <code>String</code> assuming it is - * unsigned in base 16. - * - * @param i the <code>int</code> to convert to <code>String</code> - * @return the <code>String</code> representation of the argument - */ - public static String toHexString(int i) - { - return toUnsignedString(i, 4); - } - - /** - * Converts the <code>int</code> to a <code>String</code> assuming it is - * unsigned in base 8. - * - * @param i the <code>int</code> to convert to <code>String</code> - * @return the <code>String</code> representation of the argument - */ - public static String toOctalString(int i) - { - return toUnsignedString(i, 3); - } - - /** - * Converts the <code>int</code> to a <code>String</code> assuming it is - * unsigned in base 2. - * - * @param i the <code>int</code> to convert to <code>String</code> - * @return the <code>String</code> representation of the argument - */ - public static String toBinaryString(int i) - { - return toUnsignedString(i, 1); - } - - /** - * Converts the <code>int</code> to a <code>String</code> and assumes - * a radix of 10. - * - * @param i the <code>int</code> to convert to <code>String</code> - * @return the <code>String</code> representation of the argument - * @see #toString(int, int) - */ - public static String toString(int i) - { - // This is tricky: in libgcj, String.valueOf(int) is a fast native - // implementation. In Classpath it just calls back to - // Integer.toString(int, int). - return String.valueOf(i); - } - - /** - * Converts the specified <code>String</code> into an <code>int</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 str 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>int</code> - * @throws NumberFormatException if <code>s</code> cannot be parsed as an - * <code>int</code> - */ - public static int parseInt(String str, int radix) - { - return parseInt(str, radix, false); - } - - /** - * Converts the specified <code>String</code> into an <code>int</code>. - * This function assumes a radix of 10. - * - * @param s the <code>String</code> to convert - * @return the <code>int</code> value of <code>s</code> - * @throws NumberFormatException if <code>s</code> cannot be parsed as an - * <code>int</code> - * @see #parseInt(String, int) - */ - public static int parseInt(String s) - { - return parseInt(s, 10, false); - } - - /** - * Creates a new <code>Integer</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>Integer</code> - * @throws NumberFormatException if <code>s</code> cannot be parsed as an - * <code>int</code> - * @see #parseInt(String, int) - */ - public static Integer valueOf(String s, int radix) - { - return valueOf(parseInt(s, radix, false)); - } - - /** - * Creates a new <code>Integer</code> object using the <code>String</code>, - * assuming a radix of 10. - * - * @param s the <code>String</code> to convert - * @return the new <code>Integer</code> - * @throws NumberFormatException if <code>s</code> cannot be parsed as an - * <code>int</code> - * @see #Integer(String) - * @see #parseInt(String) - */ - public static Integer valueOf(String s) - { - return valueOf(parseInt(s, 10, false)); - } - - /** - * Returns an <code>Integer</code> object wrapping the value. - * In contrast to the <code>Integer</code> constructor, this method - * will cache some values. It is used by boxing conversion. - * - * @param val the value to wrap - * @return the <code>Integer</code> - */ - public static Integer valueOf(int val) - { - if (val < MIN_CACHE || val > MAX_CACHE) - return new Integer(val); - else - return intCache[val - MIN_CACHE]; - } - - /** - * Return the value of this <code>Integer</code> as a <code>byte</code>. - * - * @return the byte value - */ - public byte byteValue() - { - return (byte) value; - } - - /** - * Return the value of this <code>Integer</code> as a <code>short</code>. - * - * @return the short value - */ - public short shortValue() - { - return (short) value; - } - - /** - * Return the value of this <code>Integer</code>. - * @return the int value - */ - public int intValue() - { - return value; - } - - /** - * Return the value of this <code>Integer</code> as a <code>long</code>. - * - * @return the long value - */ - public long longValue() - { - return value; - } - - /** - * Return the value of this <code>Integer</code> as a <code>float</code>. - * - * @return the float value - */ - public float floatValue() - { - return value; - } - - /** - * Return the value of this <code>Integer</code> as a <code>double</code>. - * - * @return the double value - */ - public double doubleValue() - { - return value; - } - - /** - * Converts the <code>Integer</code> value to a <code>String</code> and - * assumes a radix of 10. - * - * @return the <code>String</code> representation - */ - public String toString() - { - return String.valueOf(value); - } - - /** - * Return a hashcode representing this Object. <code>Integer</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>Integer</code> and represents the same int value. - * - * @param obj the object to compare - * @return whether these Objects are semantically equal - */ - public boolean equals(Object obj) - { - return obj instanceof Integer && value == ((Integer) obj).value; - } - - /** - * Get the specified system property as an <code>Integer</code>. The - * <code>decode()</code> method will be used to interpret the value of - * the property. - * - * @param nm the name of the system property - * @return the system property as an <code>Integer</code>, or null if the - * property is not found or cannot be decoded - * @throws SecurityException if accessing the system property is forbidden - * @see System#getProperty(String) - * @see #decode(String) - */ - public static Integer getInteger(String nm) - { - return getInteger(nm, null); - } - - /** - * Get the specified system property as an <code>Integer</code>, or use a - * default <code>int</code> value if the property is not found or is not - * decodable. The <code>decode()</code> method will be used to interpret - * the value of the property. - * - * @param nm the name of the system property - * @param val the default value - * @return the value of the system property, or the default - * @throws SecurityException if accessing the system property is forbidden - * @see System#getProperty(String) - * @see #decode(String) - */ - public static Integer getInteger(String nm, int val) - { - Integer result = getInteger(nm, null); - return result == null ? valueOf(val) : result; - } - - /** - * Get the specified system property as an <code>Integer</code>, or use a - * default <code>Integer</code> value if the property is not found or is - * not decodable. The <code>decode()</code> method will be used to - * interpret the value of the property. - * - * @param nm the name of the system property - * @param def the default value - * @return the value of the system property, or the default - * @throws SecurityException if accessing the system property is forbidden - * @see System#getProperty(String) - * @see #decode(String) - */ - public static Integer getInteger(String nm, Integer def) - { - if (nm == null || "".equals(nm)) - return def; - nm = System.getProperty(nm); - if (nm == null) - return def; - try - { - return decode(nm); - } - catch (NumberFormatException e) - { - return def; - } - } - - /** - * Convert the specified <code>String</code> into an <code>Integer</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 str the <code>String</code> to interpret - * @return the value of the String as an <code>Integer</code> - * @throws NumberFormatException if <code>s</code> cannot be parsed as a - * <code>int</code> - * @throws NullPointerException if <code>s</code> is null - * @since 1.2 - */ - public static Integer decode(String str) - { - return valueOf(parseInt(str, 10, true)); - } - - /** - * Compare two Integers numerically by comparing their <code>int</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 i the Integer to compare - * @return the comparison - * @since 1.2 - */ - public int compareTo(Integer i) - { - if (value == i.value) - return 0; - // Returns just -1 or 1 on inequality; doing math might overflow. - return value > i.value ? 1 : -1; - } - - /** - * Compares two unboxed int values. - * The result is positive if the first is greater, negative if the second - * is greater, and 0 if the two are equal. - * - * @param x First value to compare. - * @param y Second value to compare. - * - * @return positive int if the first value is greater, negative if the second - * is greater, and 0 if the two are equal. - * @since 1.7 - */ - public static int compare(int x, int y) - { - return Integer.valueOf(x).compareTo(Integer.valueOf(y)); - } - - /** - * Return the number of bits set in x. - * @param x value to examine - * @since 1.5 - */ - public static int bitCount(int x) - { - // Successively collapse alternating bit groups into a sum. - x = ((x >> 1) & 0x55555555) + (x & 0x55555555); - x = ((x >> 2) & 0x33333333) + (x & 0x33333333); - x = ((x >> 4) & 0x0f0f0f0f) + (x & 0x0f0f0f0f); - x = ((x >> 8) & 0x00ff00ff) + (x & 0x00ff00ff); - return ((x >> 16) & 0x0000ffff) + (x & 0x0000ffff); - } - - /** - * Rotate x to the left by distance bits. - * @param x the value to rotate - * @param distance the number of bits by which to rotate - * @since 1.5 - */ - public static int rotateLeft(int x, int distance) - { - // This trick works because the shift operators implicitly mask - // the shift count. - return (x << distance) | (x >>> - distance); - } - - /** - * Rotate x to the right by distance bits. - * @param x the value to rotate - * @param distance the number of bits by which to rotate - * @since 1.5 - */ - public static int rotateRight(int x, int distance) - { - // This trick works because the shift operators implicitly mask - // the shift count. - return (x << - distance) | (x >>> distance); - } - - /** - * Find the highest set bit in value, and return a new value - * with only that bit set. - * @param value the value to examine - * @since 1.5 - */ - public static int highestOneBit(int value) - { - value |= value >>> 1; - value |= value >>> 2; - value |= value >>> 4; - value |= value >>> 8; - value |= value >>> 16; - return value ^ (value >>> 1); - } - - /** - * Return the number of leading zeros in value. - * @param value the value to examine - * @since 1.5 - */ - public static int numberOfLeadingZeros(int value) - { - value |= value >>> 1; - value |= value >>> 2; - value |= value >>> 4; - value |= value >>> 8; - value |= value >>> 16; - return bitCount(~value); - } - - /** - * Find the lowest set bit in value, and return a new value - * with only that bit set. - * @param value the value to examine - * @since 1.5 - */ - public static int lowestOneBit(int value) - { - // Classic assembly trick. - return value & - value; - } - - /** - * Find the number of trailing zeros in value. - * @param value the value to examine - * @since 1.5 - */ - public static int numberOfTrailingZeros(int value) - { - return bitCount((value & -value) - 1); - } - - /** - * Return 1 if x is positive, -1 if it is negative, and 0 if it is - * zero. - * @param x the value to examine - * @since 1.5 - */ - public static int signum(int x) - { - return (x >> 31) | (-x >>> 31); - - // The LHS propagates the sign bit through every bit in the word; - // if X < 0, every bit is set to 1, else 0. if X > 0, the RHS - // negates x and shifts the resulting 1 in the sign bit to the - // LSB, leaving every other bit 0. - - // Hacker's Delight, Section 2-7 - } - - /** - * Reverse the bytes in val. - * @since 1.5 - */ - public static int reverseBytes(int val) - { - return ( ((val >> 24) & 0xff) - | ((val >> 8) & 0xff00) - | ((val << 8) & 0xff0000) - | ((val << 24) & 0xff000000)); - } - - /** - * Reverse the bits in val. - * @since 1.5 - */ - public static int reverse(int val) - { - // Successively swap alternating bit groups. - val = ((val >> 1) & 0x55555555) + ((val << 1) & ~0x55555555); - val = ((val >> 2) & 0x33333333) + ((val << 2) & ~0x33333333); - val = ((val >> 4) & 0x0f0f0f0f) + ((val << 4) & ~0x0f0f0f0f); - val = ((val >> 8) & 0x00ff00ff) + ((val << 8) & ~0x00ff00ff); - return ((val >> 16) & 0x0000ffff) + ((val << 16) & ~0x0000ffff); - } - - /** - * Helper for converting unsigned numbers to String. - * - * @param num the number - * @param exp log2(digit) (ie. 1, 3, or 4 for binary, oct, hex) - */ - // Package visible for use by Long. - static String toUnsignedString(int num, int exp) - { - // Compute string length - int size = 1; - int copy = num >>> exp; - while (copy != 0) - { - size++; - copy >>>= exp; - } - // Quick path for single character strings - if (size == 1) - return new String(digits, num, 1, true); - - // Encode into buffer - int mask = (1 << exp) - 1; - char[] buffer = new char[size]; - int i = size; - do - { - buffer[--i] = digits[num & mask]; - num >>>= exp; - } - while (num != 0); - - // Package constructor avoids an array copy. - return new String(buffer, i, size - i, true); - } - - /** - * Helper for parsing ints, used by Integer, Short, and Byte. - * - * @param str the string to parse - * @param radix the radix to use, must be 10 if decode is true - * @param decode if called from decode - * @return the parsed int value - * @throws NumberFormatException if there is an error - * @throws NullPointerException if decode is true and str if null - * @see #parseInt(String, int) - * @see #decode(String) - * @see Byte#parseByte(String, int) - * @see Short#parseShort(String, int) - */ - static int parseInt(String str, int radix, boolean decode) - { - if (! decode && str == null) - throw new NumberFormatException(); - int index = 0; - int len = str.length(); - boolean isNeg = false; - if (len == 0) - throw new NumberFormatException("string length is null"); - int ch = str.charAt(index); - if (ch == '-') - { - if (len == 1) - throw new NumberFormatException("pure '-'"); - isNeg = true; - ch = str.charAt(++index); - } - else if (ch == '+') - { - if (len == 1) - throw new NumberFormatException("pure '+'"); - ch = str.charAt(++index); - } - if (decode) - { - if (ch == '0') - { - if (++index == len) - return 0; - if ((str.charAt(index) & ~('x' ^ 'X')) == 'X') - { - radix = 16; - index++; - } - else - radix = 8; - } - else if (ch == '#') - { - radix = 16; - index++; - } - } - if (index == len) - throw new NumberFormatException("non terminated number: " + str); - - int max = MAX_VALUE / radix; - // We can't directly write `max = (MAX_VALUE + 1) / radix'. - // So instead we fake it. - if (isNeg && MAX_VALUE % radix == radix - 1) - ++max; - - int val = 0; - while (index < len) - { - if (val < 0 || val > max) - throw new NumberFormatException("number overflow (pos=" + index + ") : " + str); - - ch = Character.digit(str.charAt(index++), radix); - val = val * radix + ch; - if (ch < 0 || (val < 0 && (! isNeg || val != MIN_VALUE))) - throw new NumberFormatException("invalid character at position " + index + " in " + str); - } - return isNeg ? -val : val; - } -} |