Ints (Guava: Google Core Libraries for Java 16.0 API)

java.lang.Object
- com.google.common.primitives.Ints

```
@GwtCompatible(emulated=true)
public final class Ints
extends Object
```
Static utility methods pertaining to int primitives, that are not already found in either Integer or Arrays.
See the Guava User Guide article on primitive utilities.

Since:

1.0

Author:

Kevin Bourrillion

Field Summary

Fields
Modifier and Type	Field and Description
`static int`	`BYTES` The number of bytes required to represent a primitive `int` value.
`static int`	`MAX_POWER_OF_TWO` The largest power of two that can be represented as an `int`.

Method Summary

Methods
Modifier and Type	Method and Description
`static List<Integer>`	`asList(int... backingArray)` Returns a fixed-size list backed by the specified array, similar to `Arrays.asList(Object[])`.
`static int`	`checkedCast(long value)` Returns the `int` value that is equal to `value`, if possible.
`static int`	`compare(int a, int b)` Compares the two specified `int` values.
`static int[]`	`concat(int[]... arrays)` Returns the values from each provided array combined into a single array.
`static boolean`	`contains(int[] array, int target)` Returns `true` if `target` is present as an element anywhere in `array`.
`static int[]`	`ensureCapacity(int[] array, int minLength, int padding)` Returns an array containing the same values as `array`, but guaranteed to be of a specified minimum length.
`static int`	`fromByteArray(byte[] bytes)` Returns the `int` value whose big-endian representation is stored in the first 4 bytes of `bytes`; equivalent to `ByteBuffer.wrap(bytes).getInt()`.
`static int`	`fromBytes(byte b1, byte b2, byte b3, byte b4)` Returns the `int` value whose byte representation is the given 4 bytes, in big-endian order; equivalent to `Ints.fromByteArray(new byte[] {b1, b2, b3, b4})`.
`static int`	`hashCode(int value)` Returns a hash code for `value`; equal to the result of invoking `((Integer) value).hashCode()`.
`static int`	`indexOf(int[] array, int target)` Returns the index of the first appearance of the value `target` in `array`.
`static int`	`indexOf(int[] array, int[] target)` Returns the start position of the first occurrence of the specified `target` within `array`, or `-1` if there is no such occurrence.
`static String`	`join(String separator, int... array)` Returns a string containing the supplied `int` values separated by `separator`.
`static int`	`lastIndexOf(int[] array, int target)` Returns the index of the last appearance of the value `target` in `array`.
`static Comparator<int[]>`	`lexicographicalComparator()` Returns a comparator that compares two `int` arrays lexicographically.
`static int`	`max(int... array)` Returns the greatest value present in `array`.
`static int`	`min(int... array)` Returns the least value present in `array`.
`static int`	`saturatedCast(long value)` Returns the `int` nearest in value to `value`.
`static Converter<String,Integer>`	`stringConverter()` Returns a serializable converter object that converts between strings and integers using `Integer.decode(java.lang.String)` and `Integer.toString()`.
`static int[]`	`toArray(Collection<? extends Number> collection)` Returns an array containing each value of `collection`, converted to a `int` value in the manner of `Number.intValue()`.
`static byte[]`	`toByteArray(int value)` Returns a big-endian representation of `value` in a 4-element byte array; equivalent to `ByteBuffer.allocate(4).putInt(value).array()`.
`static Integer`	`tryParse(String string)` Parses the specified string as a signed decimal integer value.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - BYTES
```
public static final int BYTES
```
    The number of bytes required to represent a primitive int value.
    
    See Also:
    Constant Field Values
  - MAX_POWER_OF_TWO
```
public static final int MAX_POWER_OF_TWO
```
    The largest power of two that can be represented as an int.
    
    Since:
    
    10.0
    
    See Also:
    Constant Field Values
- Method Detail
  - hashCode
```
public static int hashCode(int value)
```
    Returns a hash code for value; equal to the result of invoking ((Integer) value).hashCode().
    
    Parameters:
    value - a primitive int value
    
    Returns:
    a hash code for the value
  - checkedCast
```
public static int checkedCast(long value)
```
    Returns the int value that is equal to value, if possible.
    
    Parameters:
    value - any value in the range of the int type
    
    Returns:
    the int value that equals value
    
    Throws:
    
    IllegalArgumentException - if value is greater than Integer.MAX_VALUE or less than Integer.MIN_VALUE
  - saturatedCast
```
public static int saturatedCast(long value)
```
    Returns the int nearest in value to value.
    
    Parameters:
    value - any long value
    
    Returns:
    the same value cast to int if it is in the range of the int type, Integer.MAX_VALUE if it is too large, or Integer.MIN_VALUE if it is too small
  - compare
```
public static int compare(int a,
          int b)
```
    Compares the two specified int values. The sign of the value returned is the same as that of ((Integer) a).compareTo(b).
    Note: projects using JDK 7 or later should use the equivalent Integer.compare(int, int) method instead.
    
    Parameters:
    a - the first int to compare
    b - the second int to compare
    
    Returns:
    a negative value if a is less than b; a positive value if a is greater than b; or zero if they are equal
  - contains
```
public static boolean contains(int[] array,
               int target)
```
    Returns true if target is present as an element anywhere in array.
    
    Parameters:
    array - an array of int values, possibly empty
    target - a primitive int value
    
    Returns:
    true if array[i] == target for some value of i
  - indexOf
```
public static int indexOf(int[] array,
          int target)
```
    Returns the index of the first appearance of the value target in array.
    
    Parameters:
    array - an array of int values, possibly empty
    target - a primitive int value
    
    Returns:
    the least index i for which array[i] == target, or -1 if no such index exists.
  - indexOf
```
public static int indexOf(int[] array,
          int[] target)
```
    Returns the start position of the first occurrence of the specified target within array, or -1 if there is no such occurrence.
    More formally, returns the lowest index i such that java.util.Arrays.copyOfRange(array, i, i + target.length) contains exactly the same elements as target.
    
    Parameters:
    array - the array to search for the sequence target
    target - the array to search for as a sub-sequence of array
  - lastIndexOf
```
public static int lastIndexOf(int[] array,
              int target)
```
    Returns the index of the last appearance of the value target in array.
    
    Parameters:
    array - an array of int values, possibly empty
    target - a primitive int value
    
    Returns:
    the greatest index i for which array[i] == target, or -1 if no such index exists.
  - min
```
public static int min(int... array)
```
    Returns the least value present in array.
    
    Parameters:
    array - a nonempty array of int values
    
    Returns:
    the value present in array that is less than or equal to every other value in the array
    
    Throws:
    
    IllegalArgumentException - if array is empty
  - max
```
public static int max(int... array)
```
    Returns the greatest value present in array.
    
    Parameters:
    array - a nonempty array of int values
    
    Returns:
    the value present in array that is greater than or equal to every other value in the array
    
    Throws:
    
    IllegalArgumentException - if array is empty
  - concat
```
public static int[] concat(int[]... arrays)
```
    Returns the values from each provided array combined into a single array. For example, concat(new int[] {a, b}, new int[] {}, new int[] {c} returns the array {a, b, c}.
    
    Parameters:
    arrays - zero or more int arrays
    
    Returns:
    a single array containing all the values from the source arrays, in order
  - toByteArray
```
@GwtIncompatible(value="doesn\'t work")
public static byte[] toByteArray(int value)
```
    Returns a big-endian representation of value in a 4-element byte array; equivalent to ByteBuffer.allocate(4).putInt(value).array(). For example, the input value 0x12131415 would yield the byte array {0x12, 0x13, 0x14, 0x15}.
    If you need to convert and concatenate several values (possibly even of different types), use a shared ByteBuffer instance, or use ByteStreams.newDataOutput() to get a growable buffer.
  - fromByteArray
```
@GwtIncompatible(value="doesn\'t work")
public static int fromByteArray(byte[] bytes)
```
    Returns the int value whose big-endian representation is stored in the first 4 bytes of bytes; equivalent to ByteBuffer.wrap(bytes).getInt(). For example, the input byte array {0x12, 0x13, 0x14, 0x15, 0x33} would yield the int value 0x12131415.
    Arguably, it's preferable to use ByteBuffer; that library exposes much more flexibility at little cost in readability.
    
    Throws:
    
    IllegalArgumentException - if bytes has fewer than 4 elements
  - fromBytes
```
@GwtIncompatible(value="doesn\'t work")
public static int fromBytes(byte b1,
                                 byte b2,
                                 byte b3,
                                 byte b4)
```
    Returns the int value whose byte representation is the given 4 bytes, in big-endian order; equivalent to Ints.fromByteArray(new byte[] {b1, b2, b3, b4}).
    
    Since:
    
    7.0
  - stringConverter
```
@Beta
public static Converter<String,Integer> stringConverter()
```
    Returns a serializable converter object that converts between strings and integers using Integer.decode(java.lang.String) and Integer.toString().
    
    Since:
    
    16.0
  - ensureCapacity
```
public static int[] ensureCapacity(int[] array,
                   int minLength,
                   int padding)
```
    Returns an array containing the same values as array, but guaranteed to be of a specified minimum length. If array already has a length of at least minLength, it is returned directly. Otherwise, a new array of size minLength + padding is returned, containing the values of array, and zeroes in the remaining places.
    
    Parameters:
    array - the source array
    minLength - the minimum length the returned array must guarantee
    padding - an extra amount to "grow" the array by if growth is necessary
    
    Returns:
    an array containing the values of array, with guaranteed minimum length minLength
    
    Throws:
    
    IllegalArgumentException - if minLength or padding is negative
  - join
```
public static String join(String separator,
          int... array)
```
    Returns a string containing the supplied int values separated by separator. For example, join("-", 1, 2, 3) returns the string "1-2-3".
    
    Parameters:
    separator - the text that should appear between consecutive values in the resulting string (but not at the start or end)
    array - an array of int values, possibly empty
  - lexicographicalComparator
```
public static Comparator<int[]> lexicographicalComparator()
```
    Returns a comparator that compares two int arrays lexicographically. That is, it compares, using compare(int, int)), 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, [] < [1] < [1, 2] < [2].
    The returned comparator is inconsistent with Object.equals(Object) (since arrays support only identity equality), but it is consistent with Arrays.equals(int[], int[]).
    
    Since:
    
    2.0
    
    See Also:
    Lexicographical order article at Wikipedia
  - toArray
```
public static int[] toArray(Collection<? extends Number> collection)
```
    Returns an array containing each value of collection, converted to a int value in the manner of Number.intValue().
    Elements are copied from the argument collection as if by collection.toArray(). Calling this method is as thread-safe as calling that method.
    
    Parameters:
    collection - a collection of Number instances
    
    Returns:
    an array containing the same values as collection, in the same order, converted to primitives
    
    Throws:
    
    NullPointerException - if collection or any of its elements is null
    Since:
    
    1.0 (parameter was Collection<Integer> before 12.0)
  - asList
```
public static List<Integer> asList(int... backingArray)
```
    Returns a fixed-size list backed by the specified array, similar to Arrays.asList(Object[]). The list supports List.set(int, Object), but any attempt to set a value to null will result in a NullPointerException.
    The returned list maintains the values, but not the identities, of Integer objects written to or read from it. For example, whether list.get(0) == list.get(0) is true for the returned list is unspecified.
    
    Parameters:
    backingArray - the array to back the list
    
    Returns:
    a list view of the array
  - tryParse
```
@Beta
@CheckForNull
@GwtIncompatible(value="TODO")
public static Integer tryParse(String string)
```
    Parses the specified string as a signed decimal integer value. The ASCII character '-' ('\u002D') is recognized as the minus sign.
    Unlike Integer.parseInt(String), this method returns null instead of throwing an exception if parsing fails.
    Note that strings prefixed with ASCII '+' are rejected, even under JDK 7, despite the change to Integer.parseInt(String) for that version.
    
    Parameters:
    string - the string representation of an integer value
    
    Returns:
    the integer value represented by string, or null if string has a length of zero or cannot be parsed as an integer value
    Since:
    
    11.0

Class Ints

Field Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

BYTES

MAX_POWER_OF_TWO

Method Detail

hashCode

checkedCast

saturatedCast

compare

contains

indexOf

indexOf

lastIndexOf

min

max

concat

toByteArray

fromByteArray

fromBytes

stringConverter

ensureCapacity

join

lexicographicalComparator

toArray

asList

tryParse