org.apache.hadoop.hbase.util
Class CollectionUtils

java.lang.Object
  org.apache.hadoop.hbase.util.CollectionUtils

@InterfaceAudience.Private
public class CollectionUtils
extends Object

Utility methods for dealing with Collections, including treating null collections as empty.

Constructor Summary

CollectionUtils()

Method Summary

static <T> T	getFirst(Collection<T> collection) first/last
static <T> T	getLast(List<T> list)
static int	getLastIndex(List<?> list)
static <T> boolean	isEmpty(Collection<T> collection) empty
static boolean	isLastIndex(List<?> list, int index)
static <T> boolean	notEmpty(Collection<T> collection)
static <T> Collection<T>	nullSafe(Collection<T> in)
static <A,B> boolean	nullSafeSameSize(Collection<A> a, Collection<B> b)
static <T> int	nullSafeSize(Collection<T> collection) size

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

CollectionUtils

public CollectionUtils()

Method Detail

nullSafe

public static <T> Collection<T> nullSafe(Collection<T> in)

nullSafeSize

public static <T> int nullSafeSize(Collection<T> collection)

size

nullSafeSameSize

public static <A,B> boolean nullSafeSameSize(Collection<A> a,
                                             Collection<B> b)

isEmpty

public static <T> boolean isEmpty(Collection<T> collection)

empty

notEmpty

public static <T> boolean notEmpty(Collection<T> collection)

getFirst

public static <T> T getFirst(Collection<T> collection)

first/last

getLastIndex

public static int getLastIndex(List<?> list)

Parameters:

list - any list

Returns:

-1 if list is empty, otherwise the max index

isLastIndex

public static boolean isLastIndex(List<?> list,
                                  int index)

Parameters:

list -

index - the index in question

Returns:

true if it is the last index or if list is empty and -1 is passed for the index param

getLast

public static <T> T getLast(List<T> list)