fast.java

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							:
								( x < 1L<<50 ?
									49 /* 6 */
								:
									50 /* 6 */
								)
							)
						:
							( x < 1L<<53 ?
								( x < 1L<<52 ?
									51 /* 6 */
								:
									52 /* 6 */
								)
							:
								( x < 1L<<54 ?
									53 /* 6 */
								:
									54 /* 6 */
								)
							)
						)
					:
						( x < 1L<<59 ?
							( x < 1L<<57 ?
								( x < 1L<<56 ?
									55 /* 6 */
								:
									56 /* 6 */
								)
							:
								( x < 1L<<58 ?
									57 /* 6 */
								:
									58 /* 6 */
								)
							)
						:
							( x < 1L<<61 ?
								( x < 1L<<60 ?
									59 /* 6 */
								:
									60 /* 6 */
								)
							:
								( x < 1L<<62 ?
									61 /* 6 */
								:
									62 /* 6 */
								)
							)
						)
					)
				)
			);
	}


	/** Computes the least significant bit of an integer.
	 *
	 * @param x an integer.
	 * @return the least significant bit of the argument (-1 for 0).
	 * @deprecated Moved to <code>dsiutils</code>.
	 */
	@Deprecated
	public static int leastSignificantBit( final int x ) {
		if ( x == 0 ) return -1;
		if ( ( x & 0xFF ) != 0 ) return BYTELSB[ x & 0xFF ];
		if ( ( x & 0xFFFF ) != 0 ) return BYTELSB[ x >>> 8 & 0xFF ] + 8;
		if ( ( x & 0xFFFFFF ) != 0 ) return BYTELSB[ x >>> 16 & 0xFF ]+ 16;
		return BYTELSB[ x >>> 24 & 0xFF ] + 24;
	}

	/** Computes the least significant bit of a long integer.
	 *
	 * @param x a long integer.
	 * @return the least significant bit of the argument (-1 for 0).
	 * @deprecated Moved to <code>dsiutils</code>.
	 */
	@Deprecated
	public static int leastSignificantBit( final long x ) {
		if ( x == 0 ) return -1;
		if ( ( x & 0xFF ) != 0 ) return BYTELSB[ (int)( x & 0xFF ) ];
		if ( ( x & 0xFFFF ) != 0 ) return BYTELSB[ (int)( x >>> 8 & 0xFF ) ] + 8;
		if ( ( x & 0xFFFFFF ) != 0 ) return BYTELSB[ (int)( x >>> 16 & 0xFF ) ] + 16;
		if ( ( x & 0xFFFFFFFFL ) != 0 ) return BYTELSB[ (int)( x >>> 24 & 0xFF ) ] + 24;
		if ( ( x & 0xFFFFFFFFFFL ) != 0 ) return BYTELSB[ (int)( x >>> 32 & 0xFF ) ] + 32;
		if ( ( x & 0xFFFFFFFFFFFFL ) != 0 ) return BYTELSB[ (int)( x >>> 40 & 0xFF ) ] + 40;
		if ( ( x & 0xFFFFFFFFFFFFFFL ) != 0 ) return BYTELSB[ (int)( x >>> 48 & 0xFF ) ] + 48;
		return BYTELSB[ (int)( x >>> 56 & 0xFF ) ] + 56;
	}
 
	
	/** Maps integers bijectively into natural numbers.
	 * 
	 * <P>This method will map a negative integer <var>x</var> to -2<var>x</var>-1 and
	 * a nonnegative integer <var>x</var> to 2<var>x</var>. It can be used to save 
	 * integers in the range [{@link Integer#MIN_VALUE}/2..{@link Integer#MAX_VALUE}/2] 
	 * (i.e., [-2<sup>30</sup>..2<sup>30</sup>-1])
	 * using the standard coding methods (which all work on natural numbers). Note
	 * that no range checks are performed.
	 * 
	 * <P>The inverse of the above map is computed by {@link #nat2int(int)}.
	 *
	 * @param x an integer.
	 * @return the argument mapped into a natural number.
	 * @see #nat2int(int)
	 * @deprecated Moved to <code>dsiutils</code>.
	 */

	@Deprecated
	public static int int2nat( final int x ) {
		return x >= 0 ? x << 1 : -( ( x << 1 ) + 1 );
	}

	/** Maps natural numbers bijectively into integers.
	 * 
	 * <P>This method computes the inverse of {@link #int2nat(int)}.
	 *
	 * @param x a natural  number.
	 * @return the argument mapped into an integer.
	 * @see #int2nat(int)
	 * @deprecated Moved to <code>dsiutils</code>.
	 */

	@Deprecated
	public static int nat2int( final int x ) {
		return x % 2 == 0 ? x >> 1 : -( x >> 1 ) - 1;
	}

	/** Maps longs bijectively into long natural numbers.
	 * 
	 * <P>This method will map a negative long <var>x</var> to -2<var>x</var>-1 and
	 * a nonnegative long <var>x</var> to 2<var>x</var>. It can be used to save 
	 * longs in the range [{@link Long#MIN_VALUE}/2..{@link Long#MAX_VALUE}/2] 
	 * (i.e., [-2<sup>62</sup>..2<sup>62</sup>-1])
	 * using the standard coding methods (which all work on natural numbers). Note
	 * that no range checks are performed.
	 * 
	 * <P>The inverse of the above map is computed by {@link #nat2int(long)}.
	 *
	 * @param x a long.
	 * @return the argument mapped into a long natural number.
	 * @see #int2nat(int)
	 * @deprecated Moved to <code>dsiutils</code>.
	 */

	@Deprecated
	public static long int2nat( final long x ) {
		return x >= 0 ? x << 1 : -( ( x << 1 ) + 1 );
	}

	/** Maps long natural numbers bijectively into longs.
	 * 
	 * <P>This method computes the inverse of {@link #int2nat(long)}.
	 *
	 * @param x a long natural  number.
	 * @return the argument mapped into a long.
	 * @see #nat2int(int)
	 * @deprecated Moved to <code>dsiutils</code>.
	 */

	@Deprecated
	public static long nat2int( final long x ) {
		return x % 2 == 0 ? x >> 1 : -( x >> 1 ) - 1;
	}

	/** A reasonable format for real numbers. */
	private static final java.text.NumberFormat FORMAT_DOUBLE = new java.text.DecimalFormat( "#,##0.00" );
	
	/** Formats a number.
	 *
	 * <P>This method formats a double separating thousands and printing just two fractional digits.
	 * @param d a number.
	 * @return a string containing a pretty print of the number.
	 * @deprecated Moved to <code>dsiutils</code>.
	 */
	@Deprecated
	public static String format( final double d ) {
		final StringBuffer s = new StringBuffer();
		return FORMAT_DOUBLE.format( d, s, new java.text.FieldPosition( 0 ) ).toString();
	}
	
	/** A reasonable format for integers. */
	private static final java.text.NumberFormat FORMAT_LONG = new java.text.DecimalFormat( "#,###" );
	
	/** Formats a number.
	 *
	 * <P>This method formats a long separating thousands.
	 * @param l a number.
	 * @return a string containing a pretty print of the number.
	 * @deprecated Moved to <code>dsiutils</code>.
	 */
	@Deprecated
	public static String format( final long l ) {
		final StringBuffer s = new StringBuffer();
		return FORMAT_LONG.format( l, s, new java.text.FieldPosition( 0 ) ).toString();
	}

	/** Formats a size.
	 *
	 * <P>This method formats a long using suitable unit multipliers (e.g., <samp>K</samp>, <samp>M</samp>, <samp>G</samp>, and <samp>T</samp>)
	 * and printing just two fractional digits.
	 * @param l a number, representing a size (e.g., memory).
	 * @return a string containing a pretty print of the number using unit multipliers.
	 * @deprecated Moved to <code>dsiutils</code>.
	 */
	@Deprecated
	public static String formatSize( final long l ) {
		if ( l >= 1000000000000L ) return format( l / 1000000000000.0 ) + "T";
		if ( l >= 1000000000L ) return format( l / 1000000000.0 ) + "G";
		if ( l >= 1000000L ) return format( l / 1000000.0 ) + "M";
		if ( l >= 1000L ) return format( l / 1000.0 ) + "K";
		return Long.toString( l );
	}

	/** Formats a binary size.
	 *
	 * <P>This method formats a long using suitable unit binary multipliers (e.g., <samp>Ki</samp>, <samp>Mi</samp>, <samp>Gi</samp>, and <samp>Ti</samp>)
	 * and printing <em>no</em> fractional digits. The argument must be a power of 2.
	 * @param l a number, representing a binary size (e.g., memory); must be a power of 2.
	 * @return a string containing a pretty print of the number using binary unit multipliers.
	 * @deprecated Moved to <code>dsiutils</code>.
	 */
	@Deprecated
	public static String formatBinarySize( final long l ) {
		if ( ( l & -l ) != l ) throw new IllegalArgumentException( "Not a power of 2: " + l );
		if ( l >= ( 1L << 40 ) ) return format( l >> 40 ) + "Ti";
		if ( l >= ( 1L << 30 ) ) return format( l >> 30 ) + "Gi";
		if ( l >= ( 1L << 20 ) ) return format( l >> 20 ) + "Mi";
		if ( l >= ( 1L << 10 ) ) return format( l >> 10 ) + "Ki";
		return Long.toString( l );
	}

	/** Precomputed least significant bits for bytes (-1 for 0 ). 
	 * @deprecated Moved to <code>dsiutils</code>.
	 */
	@Deprecated
	public static final int[] BYTELSB = {
		-1, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0,
		4, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0,
		5, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0,
		4, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0,
		6, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0,
		4, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0,
		5, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0,
		4, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0,
		7, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0,
		4, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0,
		5, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0,
		4, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0,
		6, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0,
		4, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0,
		5, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0,
		4, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0
	};
	    

	/** Precomputed most significant bits for bytes (-1 for 0 ). 
	 * @deprecated Moved to <code>dsiutils</code>.
	 */
	@Deprecated
	public static final int[] BYTEMSB = {
		-1, 0, 1, 1, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3, 3, 
		4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 
		5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 
		5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 
		6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 
		6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 
		6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 
		6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 
		7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 
		7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 
		7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 
		7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 
		7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
		7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 
		7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 
		7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7
	};
	
	/** Checks whether Log4J is properly configuring by searching for appenders in all loggers.
	 * 
	 * @return whether Log4J is configured (or, at least, an educated guess).
	 * @deprecated Moved to <code>dsiutils</code>.
	 * 
	 */
	
	@Deprecated
	public static boolean log4JIsConfigured() {
		if ( Logger.getRootLogger().getAllAppenders().hasMoreElements() ) return true;
		Enumeration<?> loggers = LogManager.getCurrentLoggers();
		while ( loggers.hasMoreElements() ) {
			Logger logger = (Logger)loggers.nextElement();
			if ( logger.getAllAppenders().hasMoreElements() ) return true;
		}
		return false;
	}
	
	/** Ensures that Log4J is configured, by invoking, if necessary,
	 * {@link org.apache.log4j.BasicConfigurator#configure()}, and
	 * setting the root logger level to {@link Level#INFO}.
	 * @deprecated Moved to <code>dsiutils</code>.
	 */
	
	@Deprecated
	public static void ensureLog4JIsConfigured() {
		ensureLog4JIsConfigured( Level.INFO );
	}
	
	/** Ensures that Log4J is configured, by invoking, if necessary,
	 * {@link org.apache.log4j.BasicConfigurator#configure()}, and
	 * setting the root logger level to <code>level</code>.
	 * 
	 * @param level the required logging level.
	 * @deprecated Moved to <code>dsiutils</code>.
	 */
	
	@Deprecated
	public static void ensureLog4JIsConfigured( final Level level ) {
		if ( ! log4JIsConfigured() ) {
			System.err.println( "WARNING: MG4J is autoconfiguring Log4J. You should configure Log4J properly instead." );
			BasicConfigurator.configure();
			LogManager.getRootLogger().setLevel( level );
		}
	}
	
	/** Calls Log4J's {@link Logger#getLogger(java.lang.Class)} method and then {@link #ensureLog4JIsConfigured()}.
	 * 
	 * @param klass a class that will be passed to {@link Logger#getLogger(java.lang.Class)}.
	 * @return the logger returned by {@link Logger#getLogger(java.lang.Class)}.
	 * @deprecated Moved to <code>dsiutils</code>.
	 */
	
	@Deprecated
	public static Logger getLogger( final Class<?> klass ) {
		Logger logger = Logger.getLogger( klass );
		ensureLog4JIsConfigured();
		return logger;
	}
	
	private final static Runtime RUNTIME = Runtime.getRuntime();
	
	/** Returns true if less then 5% of the available memory is free.
	 * 
	 * @return true if less then 5% of the available memory is free.
	 * @deprecated Moved to <code>dsiutils</code>.
	 */
	@Deprecated
	public static boolean memoryIsLow() {
		return availableMemory() * 100 < RUNTIME.totalMemory() * 5; 
	}

	/** Returns the amount of available memory (free memory plus never allocated memory).
	 * 
	 * @return the amount of available memory, in bytes.
	 * @deprecated Moved to <code>dsiutils</code>.
	 */
	@Deprecated
	public static long availableMemory() {
		return RUNTIME.freeMemory() + ( RUNTIME.maxMemory() - RUNTIME.totalMemory() ); 
	}

	/** Returns the percentage of available memory (free memory plus never allocated memory).
	 * 
	 * @return the percentage of available memory.
	 * @deprecated Moved to <code>dsiutils</code>.
	 */
	@Deprecated
	public static int percAvailableMemory() {
		return (int)( ( Fast.availableMemory() * 100 ) / Runtime.getRuntime().maxMemory() ); 
	}

	/** Tries to compact memory as much as possible by forcing garbage collection.
	 * @deprecated Moved to <code>dsiutils</code>.
	 */
	@Deprecated
	public static void compactMemory() {
		try {
			@SuppressWarnings("unused")
			final byte[][] unused = new byte[ 128 ][]; 
			for( int i = unused.length; i-- != 0; ) unused[ i ] = new byte[ 2000000000 ];
		}
		catch ( OutOfMemoryError itsWhatWeWanted ) {}
	}
}