guava/src/com/google/common/primitives/Longs.java - platform/external/guava - Git at Google

 /*
  * Copyright (C) 2008 The Guava Authors
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
  * http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */

 package com.google.common.primitives;

 import static com.google.common.base.Preconditions.checkArgument;
 import static com.google.common.base.Preconditions.checkElementIndex;
 import static com.google.common.base.Preconditions.checkNotNull;
 import static com.google.common.base.Preconditions.checkPositionIndexes;

 import com.google.common.annotations.Beta;
 import com.google.common.annotations.GwtCompatible;
 import com.google.common.base.Converter;

 import java.io.Serializable;
 import java.util.AbstractList;
 import java.util.Arrays;
 import java.util.Collection;
 import java.util.Collections;
 import java.util.Comparator;
 import java.util.List;
 import java.util.RandomAccess;

 /**
  * Static utility methods pertaining to {@code long} primitives, that are not
  * already found in either {@link Long} or {@link Arrays}.
  *
  * <p>See the Guava User Guide article on <a href=
  * "http://code.google.com/p/guava-libraries/wiki/PrimitivesExplained">
  * primitive utilities</a>.
  *
  * @author Kevin Bourrillion
  * @since 1.0
  */
 @GwtCompatible
 public final class Longs {
   private Longs() {}

   /**
    * The number of bytes required to represent a primitive {@code long}
    * value.
    */
   public static final int BYTES = Long.SIZE / Byte.SIZE;

   /**
    * The largest power of two that can be represented as a {@code long}.
    *
    * @since 10.0
    */
   public static final long MAX_POWER_OF_TWO = 1L << (Long.SIZE - 2);

   /**
    * Returns a hash code for {@code value}; equal to the result of invoking
    * {@code ((Long) value).hashCode()}.
    *
    * <p>This method always return the value specified by {@link
    * Long#hashCode()} in java, which might be different from
    * {@code ((Long) value).hashCode()} in GWT because {@link Long#hashCode()}
    * in GWT does not obey the JRE contract.
    *
    * @param value a primitive {@code long} value
    * @return a hash code for the value
    */
   public static int hashCode(long value) {
     return (int) (value ^ (value >>> 32));
   }

   /**
    * Compares the two specified {@code long} values. The sign of the value
    * returned is the same as that of {@code ((Long) a).compareTo(b)}.
    *
    * <p><b>Note:</b> projects using JDK 7 or later should use the equivalent
    * {@link Long#compare} method instead.
    *
    * @param a the first {@code long} to compare
    * @param b the second {@code long} to compare
    * @return a negative value if {@code a} is less than {@code b}; a positive
    *     value if {@code a} is greater than {@code b}; or zero if they are equal
    */
   public static int compare(long a, long b) {
     return (a < b) ? -1 : ((a > b) ? 1 : 0);
   }

   /**
    * Returns {@code true} if {@code target} is present as an element anywhere in
    * {@code array}.
    *
    * @param array an array of {@code long} values, possibly empty
    * @param target a primitive {@code long} value
    * @return {@code true} if {@code array[i] == target} for some value of {@code
    *     i}
    */
   public static boolean contains(long[] array, long target) {
     for (long value : array) {
       if (value == target) {
         return true;
       }
     }
     return false;
   }

   /**
    * Returns the index of the first appearance of the value {@code target} in
    * {@code array}.
    *
    * @param array an array of {@code long} values, possibly empty
    * @param target a primitive {@code long} value
    * @return the least index {@code i} for which {@code array[i] == target}, or
    *     {@code -1} if no such index exists.
    */
   public static int indexOf(long[] array, long target) {
     return indexOf(array, target, 0, array.length);
   }

   // TODO(kevinb): consider making this public
   private static int indexOf(
       long[] array, long target, int start, int end) {
     for (int i = start; i < end; i++) {
       if (array[i] == target) {
         return i;
       }
     }
     return -1;
   }

   /**
    * Returns the start position of the first occurrence of the specified {@code
    * target} within {@code array}, or {@code -1} if there is no such occurrence.
    *
    * <p>More formally, returns the lowest index {@code i} such that {@code
    * java.util.Arrays.copyOfRange(array, i, i + target.length)} contains exactly
    * the same elements as {@code target}.
    *
    * @param array the array to search for the sequence {@code target}
    * @param target the array to search for as a sub-sequence of {@code array}
    */
   public static int indexOf(long[] array, long[] target) {
     checkNotNull(array, "array");
     checkNotNull(target, "target");
     if (target.length == 0) {
       return 0;
     }

     outer:
     for (int i = 0; i < array.length - target.length + 1; i++) {
       for (int j = 0; j < target.length; j++) {
         if (array[i + j] != target[j]) {
           continue outer;
         }
       }
       return i;
     }
     return -1;
   }

   /**
    * Returns the index of the last appearance of the value {@code target} in
    * {@code array}.
    *
    * @param array an array of {@code long} values, possibly empty
    * @param target a primitive {@code long} value
    * @return the greatest index {@code i} for which {@code array[i] == target},
    *     or {@code -1} if no such index exists.
    */
   public static int lastIndexOf(long[] array, long target) {
     return lastIndexOf(array, target, 0, array.length);
   }

   // TODO(kevinb): consider making this public
   private static int lastIndexOf(
       long[] array, long target, int start, int end) {
     for (int i = end - 1; i >= start; i--) {
       if (array[i] == target) {
         return i;
       }
     }
     return -1;
   }

   /**
    * Returns the least value present in {@code array}.
    *
    * @param array a <i>nonempty</i> array of {@code long} values
    * @return the value present in {@code array} that is less than or equal to
    *     every other value in the array
    * @throws IllegalArgumentException if {@code array} is empty
    */
   public static long min(long... array) {
     checkArgument(array.length > 0);
     long min = array[0];
     for (int i = 1; i < array.length; i++) {
       if (array[i] < min) {
         min = array[i];
       }
     }
     return min;
   }

   /**
    * Returns the greatest value present in {@code array}.
    *
    * @param array a <i>nonempty</i> array of {@code long} values
    * @return the value present in {@code array} that is greater than or equal to
    *     every other value in the array
    * @throws IllegalArgumentException if {@code array} is empty
    */
   public static long max(long... array) {
     checkArgument(array.length > 0);
     long max = array[0];
     for (int i = 1; i < array.length; i++) {
       if (array[i] > max) {
         max = array[i];
       }
     }
     return max;
   }

   /**
    * Returns the values from each provided array combined into a single array.
    * For example, {@code concat(new long[] {a, b}, new long[] {}, new
    * long[] {c}} returns the array {@code {a, b, c}}.
    *
    * @param arrays zero or more {@code long} arrays
    * @return a single array containing all the values from the source arrays, in
    *     order
    */
   public static long[] concat(long[]... arrays) {
     int length = 0;
     for (long[] array : arrays) {
       length += array.length;
     }
     long[] result = new long[length];
     int pos = 0;
     for (long[] array : arrays) {
       System.arraycopy(array, 0, result, pos, array.length);
       pos += array.length;
     }
     return result;
   }

   /**
    * Returns a big-endian representation of {@code value} in an 8-element byte
    * array; equivalent to {@code ByteBuffer.allocate(8).putLong(value).array()}.
    * For example, the input value {@code 0x1213141516171819L} would yield the
    * byte array {@code {0x12, 0x13, 0x14, 0x15, 0x16, 0x17, 0x18, 0x19}}.
    *
    * <p>If you need to convert and concatenate several values (possibly even of
    * different types), use a shared {@link java.nio.ByteBuffer} instance, or use
    * {@link com.google.common.io.ByteStreams#newDataOutput()} to get a growable
    * buffer.
    */
   public static byte[] toByteArray(long value) {
     // Note that this code needs to stay compatible with GWT, which has known
     // bugs when narrowing byte casts of long values occur.
     byte[] result = new byte[8];
     for (int i = 7; i >= 0; i--) {
       result[i] = (byte) (value & 0xffL);
       value >>= 8;
     }
     return result;
   }

   /**
    * Returns the {@code long} value whose big-endian representation is
    * stored in the first 8 bytes of {@code bytes}; equivalent to {@code
    * ByteBuffer.wrap(bytes).getLong()}. For example, the input byte array
    * {@code {0x12, 0x13, 0x14, 0x15, 0x16, 0x17, 0x18, 0x19}} would yield the
    * {@code long} value {@code 0x1213141516171819L}.
    *
    * <p>Arguably, it's preferable to use {@link java.nio.ByteBuffer}; that
    * library exposes much more flexibility at little cost in readability.
    *
    * @throws IllegalArgumentException if {@code bytes} has fewer than 8
    *     elements
    */
   public static long fromByteArray(byte[] bytes) {
     checkArgument(bytes.length >= BYTES,
         "array too small: %s < %s", bytes.length, BYTES);
     return fromBytes(bytes[0], bytes[1], bytes[2], bytes[3],
         bytes[4], bytes[5], bytes[6], bytes[7]) ;
   }

   /**
    * Returns the {@code long} value whose byte representation is the given 8
    * bytes, in big-endian order; equivalent to {@code Longs.fromByteArray(new
    * byte[] {b1, b2, b3, b4, b5, b6, b7, b8})}.
    *
    * @since 7.0
    */
   public static long fromBytes(byte b1, byte b2, byte b3, byte b4,
       byte b5, byte b6, byte b7, byte b8) {
     return (b1 & 0xFFL) << 56
         | (b2 & 0xFFL) << 48
         | (b3 & 0xFFL) << 40
         | (b4 & 0xFFL) << 32
         | (b5 & 0xFFL) << 24
         | (b6 & 0xFFL) << 16
         | (b7 & 0xFFL) << 8
         | (b8 & 0xFFL);
   }

   /**
    * Parses the specified string as a signed decimal long value. The ASCII
    * character {@code '-'} (<code>'&#92;u002D'</code>) is recognized as the
    * minus sign.
    *
    * <p>Unlike {@link Long#parseLong(String)}, this method returns
    * {@code null} instead of throwing an exception if parsing fails.
    * Additionally, this method only accepts ASCII digits, and returns
    * {@code null} if non-ASCII digits are present in the string.
    *
    * <p>Note that strings prefixed with ASCII {@code '+'} are rejected, even
    * under JDK 7, despite the change to {@link Long#parseLong(String)} for
    * that version.
    *
    * @param string the string representation of a long value
    * @return the long value represented by {@code string}, or {@code null} if
    *     {@code string} has a length of zero or cannot be parsed as a long
    *     value
    * @since 14.0
    */
   @Beta
   public static Long tryParse(String string) {
     if (checkNotNull(string).length() == 0) {
       return null;
     }
     boolean negative = string.charAt(0) == '-';
     int index = negative ? 1 : 0;
     if (index == string.length()) {
       return null;
     }
     int digit = string.charAt(index++) - '0';
     if (digit < 0 || digit > 9) {
       return null;
     }
     long accum = -digit;
     while (index < string.length()) {
       digit = string.charAt(index++) - '0';
       if (digit < 0 || digit > 9 || accum < Long.MIN_VALUE / 10) {
         return null;
       }
       accum *= 10;
       if (accum < Long.MIN_VALUE + digit) {
         return null;
       }
       accum -= digit;
     }

     if (negative) {
       return accum;
     } else if (accum == Long.MIN_VALUE) {
       return null;
     } else {
       return -accum;
     }
   }

   private static final class LongConverter extends Converter<String, Long> implements Serializable {
     static final LongConverter INSTANCE = new LongConverter();

     @Override
     protected Long doForward(String value) {
       return Long.decode(value);
     }

     @Override
     protected String doBackward(Long value) {
       return value.toString();
     }

     @Override
     public String toString() {
       return "Longs.stringConverter()";
     }

     private Object readResolve() {
       return INSTANCE;
     }
     private static final long serialVersionUID = 1;
   }

   /**
    * Returns a serializable converter object that converts between strings and
    * longs using {@link Long#decode} and {@link Long#toString()}.
    *
    * @since 16.0
    */
   @Beta
   public static Converter<String, Long> stringConverter() {
     return LongConverter.INSTANCE;
   }

   /**
    * Returns an array containing the same values as {@code array}, but
    * guaranteed to be of a specified minimum length. If {@code array} already
    * has a length of at least {@code minLength}, it is returned directly.
    * Otherwise, a new array of size {@code minLength + padding} is returned,
    * containing the values of {@code array}, and zeroes in the remaining places.
    *
    * @param array the source array
    * @param minLength the minimum length the returned array must guarantee
    * @param padding an extra amount to "grow" the array by if growth is
    *     necessary
    * @throws IllegalArgumentException if {@code minLength} or {@code padding} is
    *     negative
    * @return an array containing the values of {@code array}, with guaranteed
    *     minimum length {@code minLength}
    */
   public static long[] ensureCapacity(
       long[] array, int minLength, int padding) {
     checkArgument(minLength >= 0, "Invalid minLength: %s", minLength);
     checkArgument(padding >= 0, "Invalid padding: %s", padding);
     return (array.length < minLength)
         ? copyOf(array, minLength + padding)
         : array;
   }

   // Arrays.copyOf() requires Java 6
   private static long[] copyOf(long[] original, int length) {
     long[] copy = new long[length];
     System.arraycopy(original, 0, copy, 0, Math.min(original.length, length));
     return copy;
   }

   /**
    * Returns a string containing the supplied {@code long} values separated
    * by {@code separator}. For example, {@code join("-", 1L, 2L, 3L)} returns
    * the string {@code "1-2-3"}.
    *
    * @param separator the text that should appear between consecutive values in
    *     the resulting string (but not at the start or end)
    * @param array an array of {@code long} values, possibly empty
    */
   public static String join(String separator, long... array) {
     checkNotNull(separator);
     if (array.length == 0) {
       return "";
     }

     // For pre-sizing a builder, just get the right order of magnitude
     StringBuilder builder = new StringBuilder(array.length * 10);
     builder.append(array[0]);
     for (int i = 1; i < array.length; i++) {
       builder.append(separator).append(array[i]);
     }
     return builder.toString();
   }

   /**
    * Returns a comparator that compares two {@code long} arrays
    * lexicographically. That is, it compares, using {@link
    * #compare(long, long)}), the first pair of values that follow any
    * common prefix, or when one array is a prefix of the other, treats the
    * shorter array as the lesser. For example,
    * {@code [] < [1L] < [1L, 2L] < [2L]}.
    *
    * <p>The returned comparator is inconsistent with {@link
    * Object#equals(Object)} (since arrays support only identity equality), but
    * it is consistent with {@link Arrays#equals(long[], long[])}.
    *
    * @see <a href="http://en.wikipedia.org/wiki/Lexicographical_order">
    *     Lexicographical order article at Wikipedia</a>
    * @since 2.0
    */
   public static Comparator<long[]> lexicographicalComparator() {
     return LexicographicalComparator.INSTANCE;
   }

   private enum LexicographicalComparator implements Comparator<long[]> {
     INSTANCE;

     @Override
     public int compare(long[] left, long[] right) {
       int minLength = Math.min(left.length, right.length);
       for (int i = 0; i < minLength; i++) {
         int result = Longs.compare(left[i], right[i]);
         if (result != 0) {
           return result;
         }
       }
       return left.length - right.length;
     }
   }

   /**
    * Returns an array containing each value of {@code collection}, converted to
    * a {@code long} value in the manner of {@link Number#longValue}.
    *
    * <p>Elements are copied from the argument collection as if by {@code
    * collection.toArray()}.  Calling this method is as thread-safe as calling
    * that method.
    *
    * @param collection a collection of {@code Number} instances
    * @return an array containing the same values as {@code collection}, in the
    *     same order, converted to primitives
    * @throws NullPointerException if {@code collection} or any of its elements
    *     is null
    * @since 1.0 (parameter was {@code Collection<Long>} before 12.0)
    */
   public static long[] toArray(Collection<? extends Number> collection) {
     if (collection instanceof LongArrayAsList) {
       return ((LongArrayAsList) collection).toLongArray();
     }

     Object[] boxedArray = collection.toArray();
     int len = boxedArray.length;
     long[] array = new long[len];
     for (int i = 0; i < len; i++) {
       // checkNotNull for GWT (do not optimize)
       array[i] = ((Number) checkNotNull(boxedArray[i])).longValue();
     }
     return array;
   }

   /**
    * Returns a fixed-size list backed by the specified array, similar to {@link
    * Arrays#asList(Object[])}. The list supports {@link List#set(int, Object)},
    * but any attempt to set a value to {@code null} will result in a {@link
    * NullPointerException}.
    *
    * <p>The returned list maintains the values, but not the identities, of
    * {@code Long} objects written to or read from it.  For example, whether
    * {@code list.get(0) == list.get(0)} is true for the returned list is
    * unspecified.
    *
    * @param backingArray the array to back the list
    * @return a list view of the array
    */
   public static List<Long> asList(long... backingArray) {
     if (backingArray.length == 0) {
       return Collections.emptyList();
     }
     return new LongArrayAsList(backingArray);
   }

   @GwtCompatible
   private static class LongArrayAsList extends AbstractList<Long>
       implements RandomAccess, Serializable {
     final long[] array;
     final int start;
     final int end;

     LongArrayAsList(long[] array) {
       this(array, 0, array.length);
     }

     LongArrayAsList(long[] array, int start, int end) {
       this.array = array;
       this.start = start;
       this.end = end;
     }

     @Override public int size() {
       return end - start;
     }

     @Override public boolean isEmpty() {
       return false;
     }

     @Override public Long get(int index) {
       checkElementIndex(index, size());
       return array[start + index];
     }

     @Override public boolean contains(Object target) {
       // Overridden to prevent a ton of boxing
       return (target instanceof Long)
           && Longs.indexOf(array, (Long) target, start, end) != -1;
     }

     @Override public int indexOf(Object target) {
       // Overridden to prevent a ton of boxing
       if (target instanceof Long) {
         int i = Longs.indexOf(array, (Long) target, start, end);
         if (i >= 0) {
           return i - start;
         }
       }
       return -1;
     }

     @Override public int lastIndexOf(Object target) {
       // Overridden to prevent a ton of boxing
       if (target instanceof Long) {
         int i = Longs.lastIndexOf(array, (Long) target, start, end);
         if (i >= 0) {
           return i - start;
         }
       }
       return -1;
     }

     @Override public Long set(int index, Long element) {
       checkElementIndex(index, size());
       long oldValue = array[start + index];
       // checkNotNull for GWT (do not optimize)
       array[start + index] = checkNotNull(element);
       return oldValue;
     }

     @Override public List<Long> subList(int fromIndex, int toIndex) {
       int size = size();
       checkPositionIndexes(fromIndex, toIndex, size);
       if (fromIndex == toIndex) {
         return Collections.emptyList();
       }
       return new LongArrayAsList(array, start + fromIndex, start + toIndex);
     }

     @Override public boolean equals(Object object) {
       if (object == this) {
         return true;
       }
       if (object instanceof LongArrayAsList) {
         LongArrayAsList that = (LongArrayAsList) object;
         int size = size();
         if (that.size() != size) {
           return false;
         }
         for (int i = 0; i < size; i++) {
           if (array[start + i] != that.array[that.start + i]) {
             return false;
           }
         }
         return true;
       }
       return super.equals(object);
     }

     @Override public int hashCode() {
       int result = 1;
       for (int i = start; i < end; i++) {
         result = 31 * result + Longs.hashCode(array[i]);
       }
       return result;
     }

     @Override public String toString() {
       StringBuilder builder = new StringBuilder(size() * 10);
       builder.append('[').append(array[start]);
       for (int i = start + 1; i < end; i++) {
         builder.append(", ").append(array[i]);
       }
       return builder.append(']').toString();
     }

     long[] toLongArray() {
       // Arrays.copyOfRange() is not available under GWT
       int size = size();
       long[] result = new long[size];
       System.arraycopy(array, start, result, 0, size);
       return result;
     }

     private static final long serialVersionUID = 0;
   }
 }
	/*
	* Copyright (C) 2008 The Guava Authors
	*
	* Licensed under the Apache License, Version 2.0 (the "License");
	* you may not use this file except in compliance with the License.
	* You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*/

	package com.google.common.primitives;

	import static com.google.common.base.Preconditions.checkArgument;
	import static com.google.common.base.Preconditions.checkElementIndex;
	import static com.google.common.base.Preconditions.checkNotNull;
	import static com.google.common.base.Preconditions.checkPositionIndexes;

	import com.google.common.annotations.Beta;
	import com.google.common.annotations.GwtCompatible;
	import com.google.common.base.Converter;

	import java.io.Serializable;
	import java.util.AbstractList;
	import java.util.Arrays;
	import java.util.Collection;
	import java.util.Collections;
	import java.util.Comparator;
	import java.util.List;
	import java.util.RandomAccess;

	/**
	* Static utility methods pertaining to {@code long} primitives, that are not
	* already found in either {@link Long} or {@link Arrays}.
	*
	* <p>See the Guava User Guide article on <a href=
	* "http://code.google.com/p/guava-libraries/wiki/PrimitivesExplained">
	* primitive utilities</a>.
	*
	* @author Kevin Bourrillion
	* @since 1.0
	*/
	@GwtCompatible
	public final class Longs {
	private Longs() {}

	/**
	* The number of bytes required to represent a primitive {@code long}
	* value.
	*/
	public static final int BYTES = Long.SIZE / Byte.SIZE;

	/**
	* The largest power of two that can be represented as a {@code long}.
	*
	* @since 10.0
	*/
	public static final long MAX_POWER_OF_TWO = 1L << (Long.SIZE - 2);

	/**
	* Returns a hash code for {@code value}; equal to the result of invoking
	* {@code ((Long) value).hashCode()}.
	*
	* <p>This method always return the value specified by {@link
	* Long#hashCode()} in java, which might be different from
	* {@code ((Long) value).hashCode()} in GWT because {@link Long#hashCode()}
	* in GWT does not obey the JRE contract.
	*
	* @param value a primitive {@code long} value
	* @return a hash code for the value
	*/
	public static int hashCode(long value) {
	return (int) (value ^ (value >>> 32));
	}

	/**
	* Compares the two specified {@code long} values. The sign of the value
	* returned is the same as that of {@code ((Long) a).compareTo(b)}.
	*
	* <p><b>Note:</b> projects using JDK 7 or later should use the equivalent
	* {@link Long#compare} method instead.
	*
	* @param a the first {@code long} to compare
	* @param b the second {@code long} to compare
	* @return a negative value if {@code a} is less than {@code b}; a positive
	* value if {@code a} is greater than {@code b}; or zero if they are equal
	*/
	public static int compare(long a, long b) {
	return (a < b) ? -1 : ((a > b) ? 1 : 0);
	}

	/**
	* Returns {@code true} if {@code target} is present as an element anywhere in
	* {@code array}.
	*
	* @param array an array of {@code long} values, possibly empty
	* @param target a primitive {@code long} value
	* @return {@code true} if {@code array[i] == target} for some value of {@code
	* i}
	*/
	public static boolean contains(long[] array, long target) {
	for (long value : array) {
	if (value == target) {
	return true;
	}
	}
	return false;
	}

	/**
	* Returns the index of the first appearance of the value {@code target} in
	* {@code array}.
	*
	* @param array an array of {@code long} values, possibly empty
	* @param target a primitive {@code long} value
	* @return the least index {@code i} for which {@code array[i] == target}, or
	* {@code -1} if no such index exists.
	*/
	public static int indexOf(long[] array, long target) {
	return indexOf(array, target, 0, array.length);
	}

	// TODO(kevinb): consider making this public
	private static int indexOf(
	long[] array, long target, int start, int end) {
	for (int i = start; i < end; i++) {
	if (array[i] == target) {
	return i;
	}
	}
	return -1;
	}

	/**
	* Returns the start position of the first occurrence of the specified {@code
	* target} within {@code array}, or {@code -1} if there is no such occurrence.
	*
	* <p>More formally, returns the lowest index {@code i} such that {@code
	* java.util.Arrays.copyOfRange(array, i, i + target.length)} contains exactly
	* the same elements as {@code target}.
	*
	* @param array the array to search for the sequence {@code target}
	* @param target the array to search for as a sub-sequence of {@code array}
	*/
	public static int indexOf(long[] array, long[] target) {
	checkNotNull(array, "array");
	checkNotNull(target, "target");
	if (target.length == 0) {
	return 0;
	}

	outer:
	for (int i = 0; i < array.length - target.length + 1; i++) {
	for (int j = 0; j < target.length; j++) {
	if (array[i + j] != target[j]) {
	continue outer;
	}
	}
	return i;
	}
	return -1;
	}

	/**
	* Returns the index of the last appearance of the value {@code target} in
	* {@code array}.
	*
	* @param array an array of {@code long} values, possibly empty
	* @param target a primitive {@code long} value
	* @return the greatest index {@code i} for which {@code array[i] == target},
	* or {@code -1} if no such index exists.
	*/
	public static int lastIndexOf(long[] array, long target) {
	return lastIndexOf(array, target, 0, array.length);
	}

	// TODO(kevinb): consider making this public
	private static int lastIndexOf(
	long[] array, long target, int start, int end) {
	for (int i = end - 1; i >= start; i--) {
	if (array[i] == target) {
	return i;
	}
	}
	return -1;
	}

	/**
	* Returns the least value present in {@code array}.
	*
	* @param array a <i>nonempty</i> array of {@code long} values
	* @return the value present in {@code array} that is less than or equal to
	* every other value in the array
	* @throws IllegalArgumentException if {@code array} is empty
	*/
	public static long min(long... array) {
	checkArgument(array.length > 0);
	long min = array[0];
	for (int i = 1; i < array.length; i++) {
	if (array[i] < min) {
	min = array[i];
	}
	}
	return min;
	}

	/**
	* Returns the greatest value present in {@code array}.
	*
	* @param array a <i>nonempty</i> array of {@code long} values
	* @return the value present in {@code array} that is greater than or equal to
	* every other value in the array
	* @throws IllegalArgumentException if {@code array} is empty
	*/
	public static long max(long... array) {
	checkArgument(array.length > 0);
	long max = array[0];
	for (int i = 1; i < array.length; i++) {
	if (array[i] > max) {
	max = array[i];
	}
	}
	return max;
	}

	/**
	* Returns the values from each provided array combined into a single array.
	* For example, {@code concat(new long[] {a, b}, new long[] {}, new
	* long[] {c}} returns the array {@code {a, b, c}}.
	*
	* @param arrays zero or more {@code long} arrays
	* @return a single array containing all the values from the source arrays, in
	* order
	*/
	public static long[] concat(long[]... arrays) {
	int length = 0;
	for (long[] array : arrays) {
	length += array.length;
	}
	long[] result = new long[length];
	int pos = 0;
	for (long[] array : arrays) {
	System.arraycopy(array, 0, result, pos, array.length);
	pos += array.length;
	}
	return result;
	}

	/**
	* Returns a big-endian representation of {@code value} in an 8-element byte
	* array; equivalent to {@code ByteBuffer.allocate(8).putLong(value).array()}.
	* For example, the input value {@code 0x1213141516171819L} would yield the
	* byte array {@code {0x12, 0x13, 0x14, 0x15, 0x16, 0x17, 0x18, 0x19}}.
	*
	* <p>If you need to convert and concatenate several values (possibly even of
	* different types), use a shared {@link java.nio.ByteBuffer} instance, or use
	* {@link com.google.common.io.ByteStreams#newDataOutput()} to get a growable
	* buffer.
	*/
	public static byte[] toByteArray(long value) {
	// Note that this code needs to stay compatible with GWT, which has known
	// bugs when narrowing byte casts of long values occur.
	byte[] result = new byte[8];
	for (int i = 7; i >= 0; i--) {
	result[i] = (byte) (value & 0xffL);
	value >>= 8;
	}
	return result;
	}

	/**
	* Returns the {@code long} value whose big-endian representation is
	* stored in the first 8 bytes of {@code bytes}; equivalent to {@code
	* ByteBuffer.wrap(bytes).getLong()}. For example, the input byte array
	* {@code {0x12, 0x13, 0x14, 0x15, 0x16, 0x17, 0x18, 0x19}} would yield the
	* {@code long} value {@code 0x1213141516171819L}.
	*
	* <p>Arguably, it's preferable to use {@link java.nio.ByteBuffer}; that
	* library exposes much more flexibility at little cost in readability.
	*
	* @throws IllegalArgumentException if {@code bytes} has fewer than 8
	* elements
	*/
	public static long fromByteArray(byte[] bytes) {
	checkArgument(bytes.length >= BYTES,
	"array too small: %s < %s", bytes.length, BYTES);
	return fromBytes(bytes[0], bytes[1], bytes[2], bytes[3],
	bytes[4], bytes[5], bytes[6], bytes[7]) ;
	}

	/**
	* Returns the {@code long} value whose byte representation is the given 8
	* bytes, in big-endian order; equivalent to {@code Longs.fromByteArray(new
	* byte[] {b1, b2, b3, b4, b5, b6, b7, b8})}.
	*
	* @since 7.0
	*/
	public static long fromBytes(byte b1, byte b2, byte b3, byte b4,
	byte b5, byte b6, byte b7, byte b8) {
	return (b1 & 0xFFL) << 56
	\| (b2 & 0xFFL) << 48
	\| (b3 & 0xFFL) << 40
	\| (b4 & 0xFFL) << 32
	\| (b5 & 0xFFL) << 24
	\| (b6 & 0xFFL) << 16
	\| (b7 & 0xFFL) << 8
	\| (b8 & 0xFFL);
	}

	/**
	* Parses the specified string as a signed decimal long value. The ASCII
	* character {@code '-'} (<code>'\u002D'</code>) is recognized as the
	* minus sign.
	*
	* <p>Unlike {@link Long#parseLong(String)}, this method returns
	* {@code null} instead of throwing an exception if parsing fails.
	* Additionally, this method only accepts ASCII digits, and returns
	* {@code null} if non-ASCII digits are present in the string.
	*
	* <p>Note that strings prefixed with ASCII {@code '+'} are rejected, even
	* under JDK 7, despite the change to {@link Long#parseLong(String)} for
	* that version.
	*
	* @param string the string representation of a long value
	* @return the long value represented by {@code string}, or {@code null} if
	* {@code string} has a length of zero or cannot be parsed as a long
	* value
	* @since 14.0
	*/
	@Beta
	public static Long tryParse(String string) {
	if (checkNotNull(string).length() == 0) {
	return null;
	}
	boolean negative = string.charAt(0) == '-';
	int index = negative ? 1 : 0;
	if (index == string.length()) {
	return null;
	}
	int digit = string.charAt(index++) - '0';
	if (digit < 0 \|\| digit > 9) {
	return null;
	}
	long accum = -digit;
	while (index < string.length()) {
	digit = string.charAt(index++) - '0';
	if (digit < 0 \|\| digit > 9 \|\| accum < Long.MIN_VALUE / 10) {
	return null;
	}
	accum *= 10;
	if (accum < Long.MIN_VALUE + digit) {
	return null;
	}
	accum -= digit;
	}

	if (negative) {
	return accum;
	} else if (accum == Long.MIN_VALUE) {
	return null;
	} else {
	return -accum;
	}
	}

	private static final class LongConverter extends Converter<String, Long> implements Serializable {
	static final LongConverter INSTANCE = new LongConverter();

	@Override
	protected Long doForward(String value) {
	return Long.decode(value);
	}

	@Override
	protected String doBackward(Long value) {
	return value.toString();
	}

	@Override
	public String toString() {
	return "Longs.stringConverter()";
	}

	private Object readResolve() {
	return INSTANCE;
	}
	private static final long serialVersionUID = 1;
	}

	/**
	* Returns a serializable converter object that converts between strings and
	* longs using {@link Long#decode} and {@link Long#toString()}.
	*
	* @since 16.0
	*/
	@Beta
	public static Converter<String, Long> stringConverter() {
	return LongConverter.INSTANCE;
	}

	/**
	* Returns an array containing the same values as {@code array}, but
	* guaranteed to be of a specified minimum length. If {@code array} already
	* has a length of at least {@code minLength}, it is returned directly.
	* Otherwise, a new array of size {@code minLength + padding} is returned,
	* containing the values of {@code array}, and zeroes in the remaining places.
	*
	* @param array the source array
	* @param minLength the minimum length the returned array must guarantee
	* @param padding an extra amount to "grow" the array by if growth is
	* necessary
	* @throws IllegalArgumentException if {@code minLength} or {@code padding} is
	* negative
	* @return an array containing the values of {@code array}, with guaranteed
	* minimum length {@code minLength}
	*/
	public static long[] ensureCapacity(
	long[] array, int minLength, int padding) {
	checkArgument(minLength >= 0, "Invalid minLength: %s", minLength);
	checkArgument(padding >= 0, "Invalid padding: %s", padding);
	return (array.length < minLength)
	? copyOf(array, minLength + padding)
	: array;
	}

	// Arrays.copyOf() requires Java 6
	private static long[] copyOf(long[] original, int length) {
	long[] copy = new long[length];
	System.arraycopy(original, 0, copy, 0, Math.min(original.length, length));
	return copy;
	}

	/**
	* Returns a string containing the supplied {@code long} values separated
	* by {@code separator}. For example, {@code join("-", 1L, 2L, 3L)} returns
	* the string {@code "1-2-3"}.
	*
	* @param separator the text that should appear between consecutive values in
	* the resulting string (but not at the start or end)
	* @param array an array of {@code long} values, possibly empty
	*/
	public static String join(String separator, long... array) {
	checkNotNull(separator);
	if (array.length == 0) {
	return "";
	}

	// For pre-sizing a builder, just get the right order of magnitude
	StringBuilder builder = new StringBuilder(array.length * 10);
	builder.append(array[0]);
	for (int i = 1; i < array.length; i++) {
	builder.append(separator).append(array[i]);
	}
	return builder.toString();
	}

	/**
	* Returns a comparator that compares two {@code long} arrays
	* lexicographically. That is, it compares, using {@link
	* #compare(long, long)}), the first pair of values that follow any
	* common prefix, or when one array is a prefix of the other, treats the
	* shorter array as the lesser. For example,
	* {@code [] < [1L] < [1L, 2L] < [2L]}.
	*
	* <p>The returned comparator is inconsistent with {@link
	* Object#equals(Object)} (since arrays support only identity equality), but
	* it is consistent with {@link Arrays#equals(long[], long[])}.
	*
	* @see <a href="http://en.wikipedia.org/wiki/Lexicographical_order">
	* Lexicographical order article at Wikipedia</a>
	* @since 2.0
	*/
	public static Comparator<long[]> lexicographicalComparator() {
	return LexicographicalComparator.INSTANCE;
	}

	private enum LexicographicalComparator implements Comparator<long[]> {
	INSTANCE;

	@Override
	public int compare(long[] left, long[] right) {
	int minLength = Math.min(left.length, right.length);
	for (int i = 0; i < minLength; i++) {
	int result = Longs.compare(left[i], right[i]);
	if (result != 0) {
	return result;
	}
	}
	return left.length - right.length;
	}
	}

	/**
	* Returns an array containing each value of {@code collection}, converted to
	* a {@code long} value in the manner of {@link Number#longValue}.
	*
	* <p>Elements are copied from the argument collection as if by {@code
	* collection.toArray()}. Calling this method is as thread-safe as calling
	* that method.
	*
	* @param collection a collection of {@code Number} instances
	* @return an array containing the same values as {@code collection}, in the
	* same order, converted to primitives
	* @throws NullPointerException if {@code collection} or any of its elements
	* is null
	* @since 1.0 (parameter was {@code Collection<Long>} before 12.0)
	*/
	public static long[] toArray(Collection<? extends Number> collection) {
	if (collection instanceof LongArrayAsList) {
	return ((LongArrayAsList) collection).toLongArray();
	}

	Object[] boxedArray = collection.toArray();
	int len = boxedArray.length;
	long[] array = new long[len];
	for (int i = 0; i < len; i++) {
	// checkNotNull for GWT (do not optimize)
	array[i] = ((Number) checkNotNull(boxedArray[i])).longValue();
	}
	return array;
	}

	/**
	* Returns a fixed-size list backed by the specified array, similar to {@link
	* Arrays#asList(Object[])}. The list supports {@link List#set(int, Object)},
	* but any attempt to set a value to {@code null} will result in a {@link
	* NullPointerException}.
	*
	* <p>The returned list maintains the values, but not the identities, of
	* {@code Long} objects written to or read from it. For example, whether
	* {@code list.get(0) == list.get(0)} is true for the returned list is
	* unspecified.
	*
	* @param backingArray the array to back the list
	* @return a list view of the array
	*/
	public static List<Long> asList(long... backingArray) {
	if (backingArray.length == 0) {
	return Collections.emptyList();
	}
	return new LongArrayAsList(backingArray);
	}

	@GwtCompatible
	private static class LongArrayAsList extends AbstractList<Long>
	implements RandomAccess, Serializable {
	final long[] array;
	final int start;
	final int end;

	LongArrayAsList(long[] array) {
	this(array, 0, array.length);
	}

	LongArrayAsList(long[] array, int start, int end) {
	this.array = array;
	this.start = start;
	this.end = end;
	}

	@Override public int size() {
	return end - start;
	}

	@Override public boolean isEmpty() {
	return false;
	}

	@Override public Long get(int index) {
	checkElementIndex(index, size());
	return array[start + index];
	}

	@Override public boolean contains(Object target) {
	// Overridden to prevent a ton of boxing
	return (target instanceof Long)
	&& Longs.indexOf(array, (Long) target, start, end) != -1;
	}

	@Override public int indexOf(Object target) {
	// Overridden to prevent a ton of boxing
	if (target instanceof Long) {
	int i = Longs.indexOf(array, (Long) target, start, end);
	if (i >= 0) {
	return i - start;
	}
	}
	return -1;
	}

	@Override public int lastIndexOf(Object target) {
	// Overridden to prevent a ton of boxing
	if (target instanceof Long) {
	int i = Longs.lastIndexOf(array, (Long) target, start, end);
	if (i >= 0) {
	return i - start;
	}
	}
	return -1;
	}

	@Override public Long set(int index, Long element) {
	checkElementIndex(index, size());
	long oldValue = array[start + index];
	// checkNotNull for GWT (do not optimize)
	array[start + index] = checkNotNull(element);
	return oldValue;
	}

	@Override public List<Long> subList(int fromIndex, int toIndex) {
	int size = size();
	checkPositionIndexes(fromIndex, toIndex, size);
	if (fromIndex == toIndex) {
	return Collections.emptyList();
	}
	return new LongArrayAsList(array, start + fromIndex, start + toIndex);
	}

	@Override public boolean equals(Object object) {
	if (object == this) {
	return true;
	}
	if (object instanceof LongArrayAsList) {
	LongArrayAsList that = (LongArrayAsList) object;
	int size = size();
	if (that.size() != size) {
	return false;
	}
	for (int i = 0; i < size; i++) {
	if (array[start + i] != that.array[that.start + i]) {
	return false;
	}
	}
	return true;
	}
	return super.equals(object);
	}

	@Override public int hashCode() {
	int result = 1;
	for (int i = start; i < end; i++) {
	result = 31 * result + Longs.hashCode(array[i]);
	}
	return result;
	}

	@Override public String toString() {
	StringBuilder builder = new StringBuilder(size() * 10);
	builder.append('[').append(array[start]);
	for (int i = start + 1; i < end; i++) {
	builder.append(", ").append(array[i]);
	}
	return builder.append(']').toString();
	}

	long[] toLongArray() {
	// Arrays.copyOfRange() is not available under GWT
	int size = size();
	long[] result = new long[size];
	System.arraycopy(array, start, result, 0, size);
	return result;
	}

	private static final long serialVersionUID = 0;
	}
	}