gcc/libjava/java/lang/Long.java
Tom Tromey c86e69b2f9 Long.java (parseLong): Corrected overflow detection code.
* java/lang/Long.java (parseLong): Corrected overflow detection
	code.
	* java/lang/Integer.java (parseInt): Corrected overflow detection
	code.

From-SVN: r26295
1999-04-08 11:57:28 +00:00

362 lines
8.0 KiB
Java

/* Copyright (C) 1998, 1999 Cygnus Solutions
This file is part of libgcj.
This software is copyrighted work licensed under the terms of the
Libgcj License. Please consult the file "LIBGCJ_LICENSE" for
details. */
package java.lang;
/**
* @author Warren Levy <warrenl@cygnus.com>
* @date September 18, 1998.
*/
/* Written using "Java Class Libraries", 2nd edition, ISBN 0-201-31002-3
* "The Java Language Specification", ISBN 0-201-63451-1
* plus online API docs for JDK 1.2 beta from http://www.javasoft.com.
* Status: Believed complete and correct.
*/
public final class Long extends Number implements Comparable
{
public static final long MAX_VALUE = 0x7FFFFFFFFFFFFFFFL;
public static final long MIN_VALUE = 0x8000000000000000L;
// This initialization is seemingly circular, but it is accepted
// by javac, and is handled specially by gcc.
public static final Class TYPE = long.class;
/* The long value of the instance. */
private long value;
public Long(long val)
{
value = val;
}
public Long(String str) throws NumberFormatException
{
value = parseLong(str, 10);
}
public byte byteValue()
{
return (byte) value;
}
public double doubleValue()
{
return (double) value;
}
public float floatValue()
{
return (float) value;
}
public int intValue()
{
return (int) value;
}
public long longValue()
{
return value;
}
public short shortValue()
{
return (short) value;
}
// Added in JDK 1.2
public int compareTo(Long anotherLong)
{
if (this.value == anotherLong.value)
return 0;
// Returns just -1 or 1 on inequality; doing math might overflow the long.
if (this.value > anotherLong.value)
return 1;
return -1;
}
// Added in JDK 1.2
public int compareTo(Object o) throws ClassCastException
{
if (!(o instanceof Long))
throw new ClassCastException();
return this.compareTo((Long) o);
}
// Added in JDK 1.2
public static Long decode(String str) throws NumberFormatException
{
boolean isNeg = false;
int index = 0;
int radix = 10;
final int len;
if (str == null || (len = str.length()) == 0)
throw new NumberFormatException();
// Negative numbers are always radix 10.
if (str.charAt(0) == '-')
{
radix = 10;
index++;
isNeg = true;
}
else if (str.charAt(index) == '#')
{
radix = 16;
index++;
}
else if (str.charAt(index) == '0')
{
// Check if str is just "0"
if (len == 1)
return new Long(0L);
index++;
if (str.charAt(index) == 'x')
{
radix = 16;
index++;
}
else
radix = 8;
}
if (index >= len)
throw new NumberFormatException();
return new Long(parseLong(str, index, len, isNeg, radix));
}
public boolean equals(Object obj)
{
return (obj != null && (obj instanceof Long)
&& ((Long) obj).value == value);
}
public static Long getLong(String prop)
{
return getLong(prop, null);
}
public static Long getLong(String prop, long defval)
{
Long val = getLong(prop, null);
return val == null ? new Long(defval) : val;
}
public static Long getLong(String prop, Long defobj)
{
try
{
return decode(System.getProperty(prop));
}
catch (NumberFormatException ex)
{
return defobj;
}
}
public int hashCode()
{
return (int)(this.longValue()^(this.longValue()>>>32));
}
public static long parseLong(String str) throws NumberFormatException
{
return parseLong(str, 10);
}
public static long parseLong(String str, int radix)
throws NumberFormatException
{
final int len;
if (str == null || (len = str.length()) == 0 ||
radix < Character.MIN_RADIX || radix > Character.MAX_RADIX)
throw new NumberFormatException();
boolean isNeg = false;
int index = 0;
if (str.charAt(index) == '-')
if (len > 1)
{
isNeg = true;
index++;
}
else
throw new NumberFormatException();
return parseLong(str, index, len, isNeg, radix);
}
private static long parseLong(String str, int index, int len, boolean isNeg,
int radix) throws NumberFormatException
{
long val = 0;
int digval;
long 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;
for ( ; index < len; index++)
{
if (val < 0 || val > max)
throw new NumberFormatException();
if ((digval = Character.digit(str.charAt(index), radix)) < 0)
throw new NumberFormatException();
// Throw an exception for overflow if result is negative.
// However, we special-case the most negative value.
val = val * radix + digval;
if (val < 0 && (! isNeg || val != MIN_VALUE))
throw new NumberFormatException();
}
return isNeg ? -(val) : val;
}
public static String toBinaryString(long num)
{
return toUnsignedString(num, 1);
}
public static String toHexString(long num)
{
return toUnsignedString(num, 4);
}
public static String toOctalString(long num)
{
return toUnsignedString(num, 3);
}
private static String toUnsignedString(long num, int exp)
{
// Use an array large enough for a binary number.
int radix = 1 << exp;
long mask = radix - 1;
char[] buffer = new char[64];
int i = 64;
do
{
buffer[--i] = Character.forDigit((int) (num & mask), radix);
num = num >>> exp;
}
while (num != 0);
return String.valueOf(buffer, i, 64-i);
}
public String toString()
{
return toString(this.value);
}
public static String toString(long num)
{
// Use the Integer toString for efficiency if possible.
if (num <= Integer.MAX_VALUE && num >= Integer.MIN_VALUE)
return Integer.toString((int) num);
// Use an arrary large enough for "-9223372036854775808"; i.e. 11 chars.
char[] buffer = new char[20];
int i = 20;
boolean isNeg;
if (num < 0)
{
isNeg = true;
num = -(num);
if (num < 0)
{
// Must be MIN_VALUE, so handle this special case.
buffer[--i] = '8';
num = 922337203685477580L;
}
}
else
isNeg = false;
do
{
buffer[--i] = (char) ((int) '0' + (num % 10));
num /= 10;
}
while (num > 0);
if (isNeg)
buffer[--i] = '-';
return String.valueOf(buffer, i, 20-i);
}
public static String toString(long num, int radix)
{
// Use optimized method for the typical case.
if (radix == 10 ||
radix < Character.MIN_RADIX || radix > Character.MAX_RADIX)
return toString(num);
// Use the Integer toString for efficiency if possible.
if (num <= Integer.MAX_VALUE && num >= Integer.MIN_VALUE)
return Integer.toString((int) num, radix);
// For negative numbers, print out the absolute value w/ a leading '-'.
// Use an array large enough for a binary number.
char[] buffer = new char[65];
int i = 65;
boolean isNeg;
if (num < 0)
{
isNeg = true;
num = -(num);
// When the value is MIN_VALUE, it overflows when made positive
if (num < 0)
{
buffer[--i] = Character.forDigit((int) (-(num + radix) % radix),
radix);
num = -(num / radix);
}
}
else
isNeg = false;
do
{
buffer[--i] = Character.forDigit((int) (num % radix), radix);
num /= radix;
}
while (num > 0);
if (isNeg)
buffer[--i] = '-';
return String.valueOf(buffer, i, 65-i);
}
public static Long valueOf(String str) throws NumberFormatException
{
return new Long(parseLong(str, 10));
}
public static Long valueOf(String str, int radix)
throws NumberFormatException
{
return new Long(parseLong(str, radix));
}
}