org.apache.dubbo.common.utils

Class CollectionUtils

java.lang.Object

org.apache.dubbo.common.utils.CollectionUtils

public class CollectionUtils
extends Object

Miscellaneous collection utility methods. Mainly for internal use within the framework.

Since:

2.0.7

Author:

william.liangf

Method Summary

Modifier and Type	Method and Description
static <T> int	addAll(Collection<T> collection, T... values) Add the multiple values into the specified collection
static boolean	equals(Collection<?> one, Collection<?> another) Compares the specified collection with another, the main implementation references AbstractSet
static <T> T	first(Collection<T> values) Take the first element from the specified collection
static boolean	isEmpty(Collection<?> collection) Return true if the supplied Collection is null or empty.
static boolean	isEmptyMap(Map map) Return true if the supplied Map is null or empty.
static boolean	isNotEmpty(Collection<?> collection) Return true if the supplied Collection is not null or not empty.
static boolean	isNotEmptyMap(Map map) Return true if the supplied Map is not null or not empty.
static String	join(List<String> list, String separator)
static List<String>	join(Map<String,String> map, String separator)
static Map<String,List<String>>	joinAll(Map<String,Map<String,String>> map, String separator)
static boolean	mapEquals(Map<?,?> map1, Map<?,?> map2)
static <T> Set<T>	ofSet(T... values) Convert to multiple values to be LinkedHashSet
static int	size(Collection<?> collection) Get the size of the specified Collection
static <T> List<T>	sort(List<T> list)
static List<String>	sortSimpleName(List<String> list)
static Map<String,String>	split(List<String> list, String separator)
static Map<String,Map<String,String>>	splitAll(Map<String,List<String>> list, String separator)
static <K,V> Map<K,V>	toMap(Object... pairs)
static Map<String,String>	toStringMap(String... pairs)

Methods inherited from class java.lang.Object

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

Method Detail

sort

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

sortSimpleName

public static List<String> sortSimpleName(List<String> list)

splitAll

public static Map<String,Map<String,String>> splitAll(Map<String,List<String>> list,
                                                      String separator)

joinAll

public static Map<String,List<String>> joinAll(Map<String,Map<String,String>> map,
                                               String separator)

split

public static Map<String,String> split(List<String> list,
                                       String separator)

join

public static List<String> join(Map<String,String> map,
                                String separator)

join

public static String join(List<String> list,
                          String separator)

mapEquals

public static boolean mapEquals(Map<?,?> map1,
                                Map<?,?> map2)

toStringMap

public static Map<String,String> toStringMap(String... pairs)

toMap

public static <K,V> Map<K,V> toMap(Object... pairs)

isEmpty

public static boolean isEmpty(Collection<?> collection)

Return true if the supplied Collection is null or empty. Otherwise, return false.

Parameters:

collection - the Collection to check

Returns:

whether the given Collection is empty

isNotEmpty

public static boolean isNotEmpty(Collection<?> collection)

Return true if the supplied Collection is not null or not empty. Otherwise, return false.

Parameters:

collection - the Collection to check

Returns:

whether the given Collection is not empty

isEmptyMap

public static boolean isEmptyMap(Map map)

Return true if the supplied Map is null or empty. Otherwise, return false.

Parameters:

map - the Map to check

Returns:

whether the given Map is empty

isNotEmptyMap

public static boolean isNotEmptyMap(Map map)

Return true if the supplied Map is not null or not empty. Otherwise, return false.

Parameters:

map - the Map to check

Returns:

whether the given Map is not empty

ofSet

public static <T> Set<T> ofSet(T... values)

Convert to multiple values to be LinkedHashSet

Type Parameters:

T - the type of values

Parameters:

values - one or more values

Returns:

read-only Set

size

public static int size(Collection<?> collection)

Get the size of the specified Collection

Parameters:

collection - the specified Collection

Returns:

must be positive number

Since:

2.7.6

equals

public static boolean equals(Collection<?> one,
                             Collection<?> another)

Compares the specified collection with another, the main implementation references AbstractSet

Parameters:

one - Collection

another - Collection

Returns:

if equals, return true, or false

Since:

2.7.6

addAll

public static <T> int addAll(Collection<T> collection,
                             T... values)

Add the multiple values into the specified collection

Type Parameters:

T - the type of values

Parameters:

collection - the specified collection

values - the multiple values

Returns:

the effected count after added

Since:

2.7.6

first

public static <T> T first(Collection<T> values)

Take the first element from the specified collection

Type Parameters:

T - the type of element of collection

Parameters:

values - the collection object

Returns:

if found, return the first one, or null

Since:

2.7.6