net.obvj.jep.util

Class CollectionsUtils

java.lang.Object

net.obvj.jep.util.CollectionsUtils

public class CollectionsUtils
extends Object

Utility methods for working with Java Collections.

Author:

oswaldo.bapvic.jr

Method Summary

Modifier and Type	Method and Description
static List<Object>	asList(Object object) Converts the given object into a List.
static Map<String,String>	asMap(String... entries) Accepts one or more entries as strings in the format recognized by parseMapEntry(String) and populates a Map of Strings with these associations.
static Map<Object,Object>	createMapOfParsedObjects(Iterable<?> iterable) Converts the given Iterable into a Map where each key is an element of the given Iterable, parsed either as Double or Date, and the associated value is the original element without conversion.
static List<Object>	distincList(List<Object> list) Returns a list consisting of the distinct elements (according to Object.equals(Object)) of a given list.
static boolean	isEmpty(Collection<?> collection)
static Object	max(Iterable<?> iterable) Returns the maximum element inside the given Iterable
static Object	min(Iterable<?> iterable) Returns the minimum element inside the given Iterable
static Stack<Object>	newParametersStack(Object... parameters) Produces a Stack to be processed by JEP functions.
static Map.Entry<String,String>	parseMapEntry(String entry) Parses a string into a Map.Entry.

Methods inherited from class java.lang.Object

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

Method Detail

isEmpty

public static boolean isEmpty(Collection<?> collection)

Parameters:

collection - the collection to be evaluated

Returns:

true if the given collection is either null or empty; otherwise, false.

asList

public static List<Object> asList(Object object)

Converts the given object into a List.

If the source object is either an array of Objects (primitive types not supported) or a JSONArray, it will return a List backed by the specified array. If a non-null Object is received (not a List or JSONArray), a singleton list will be returned (containing only the specified object). If a null or empty object is received, then an empty list will be returned. If the input is already a List, the same object will be returned.

Parameters:

object - the source object to be parsed into a List

Returns:

a List object

asMap

public static Map<String,String> asMap(String... entries)

Accepts one or more entries as strings in the format recognized by parseMapEntry(String) and populates a Map of Strings with these associations.

Parameters:

entries - one or more strings containing, each one, a map entry parseable by parseMapEntry(String)

Returns:

a Map containing associations for the given entries

parseMapEntry

public static Map.Entry<String,String> parseMapEntry(String entry)

Parses a string into a Map.Entry.

Parameters:

entry - a string containing a key, a separator, and a value. A separator can be either an equal sign (=) or colon (:). For example: "key1=value1" or "key2:value2"

Returns:

a Map.Entry of Strings for the given entry string

createMapOfParsedObjects

public static Map<Object,Object> createMapOfParsedObjects(Iterable<?> iterable)

Converts the given Iterable into a Map where each key is an element of the given Iterable, parsed either as Double or Date, and the associated value is the original element without conversion.

Parameters:

iterable - the Iterable to be converted

Returns:

A map contains the parsed objects as keys and the original elements as values

max

public static Object max(Iterable<?> iterable)

Returns the maximum element inside the given Iterable

Parameters:

iterable - the Iterable whose maximum element is to be evaluated

Returns:

The maximum element inside the given Iterable.

min

public static Object min(Iterable<?> iterable)

Returns the minimum element inside the given Iterable

Parameters:

iterable - the Iterable whose minimum element is to be evaluated

Returns:

The minimum element inside the given Iterable.

distincList

public static List<Object> distincList(List<Object> list)

Returns a list consisting of the distinct elements (according to Object.equals(Object)) of a given list.

Parameters:

list - the list to be processed

Returns:

a new list containing only distinct elements

newParametersStack

public static Stack<Object> newParametersStack(Object... parameters)

Produces a Stack to be processed by JEP functions.

Parameters:

parameters - the parameters to populate the stack

Returns:

a Stack with the given parameters.