org.kuali.student.common.collection

Class KSCollectionUtils

java.lang.Object

org.kuali.student.common.collection.KSCollectionUtils

public class KSCollectionUtils
extends Object

Author:

Kuali Student Team This is a common utility class for the KS project.

Constructor Summary

Constructors

Constructor and Description
KSCollectionUtils()

Method Summary

Methods

Modifier and Type	Method and Description
static <T> boolean	areCollectionContentsEqual(Collection<T> source, Collection<T> target) A Null-safe test of the contents of each list that returns true if they are identical using bag semantics.
static <T> T	getOptionalZeroElement(List<T> list) Cardinality of zero or one.
static <T> T	getOptionalZeroElement(List<T> list, boolean throwOnNullList) Cardinality of zero or one.
static <T> T	getRequiredZeroElement(List<T> list) Cardinality of one This is a generic method so you will not need to worry about casting when using this method Using get(0) in a non-test class will result in a critical sonar issue being reported which will result in a JIRA issue.
static <T> T	getRequiredZeroElement(List<T> list, boolean throwOnNullList, boolean throwOnEmptyList) Cardinality of one This is a generic method so you will not need to worry about casting when using this method Using get(0) in a non-test class will result in a critical sonar issue being reported which will result in a JIRA issue.

Methods inherited from class java.lang.Object

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

Constructor Detail

KSCollectionUtils

public KSCollectionUtils()

Method Detail

getRequiredZeroElement

public static <T> T getRequiredZeroElement(List<T> list)
                                throws OperationFailedException

Cardinality of one This is a generic method so you will not need to worry about casting when using this method Using get(0) in a non-test class will result in a critical sonar issue being reported which will result in a JIRA issue. Correcting get(0) depends on the cardinality constraints on the list. If a list constraint is changed, get(0) might not be the right answer anymore and we would prefer to expose that problem at the source rather than requiring implementers to track down the cardinality constraint enforcement in java. This is handled via OperationFailedException being thrown in the examples belowCardinality of one and only one element:

Type Parameters:

T - Type of element to return

Parameters:

list - Typed list passed into method. Cannot be null.

Returns:

the get(0) element in the list.

Throws:

OperationFailedException

getRequiredZeroElement

public static <T> T getRequiredZeroElement(List<T> list,
                           boolean throwOnNullList,
                           boolean throwOnEmptyList)
                                throws OperationFailedException

Cardinality of one This is a generic method so you will not need to worry about casting when using this method Using get(0) in a non-test class will result in a critical sonar issue being reported which will result in a JIRA issue. Correcting get(0) depends on the cardinality constraints on the list. If a list constraint is changed, get(0) might not be the right answer anymore and we would prefer to expose that problem at the source rather than requiring implementers to track down the cardinality constraint enforcement in java. This is handled via OperationFailedException being thrown in the examples belowCardinality of one and only one element:

Type Parameters:

T - Type of element to return

Parameters:

list - Typed list passed into method. Cannot be null.

throwOnNullList - true if an OperationFailedException should be thrown if the list is null. If false it will allow null to be returned in the list is null case.

throwOnEmptyList - true if an OperationFailedException should be thrown if the list is empty. If false it will allow null to be returned in the list is empty case.

Returns:

the get(0) element in the list.

Throws:

OperationFailedException

getOptionalZeroElement

public static <T> T getOptionalZeroElement(List<T> list)
                                throws OperationFailedException

Cardinality of zero or one. Will return the value or null depending on what's in the list. List has 1 element, return element. List has 0 elements, return null. else throw exception. This is a generic method so you will not need to worry about casting when using this method Using get(0) in a non-test class will result in a critical sonar issue being reported which will result in a JIRA issue. Correcting get(0) depends on the cardinality constraints on the list. If a list constraint is changed, get(0) might not be the right answer anymore and we would prefer to expose that problem at the source rather than requiring implementers to track down the cardinality constraint enforcement in java. This is handled via OperationFailedException being thrown in the examples belowCardinality of one and only one element:

Type Parameters:

T - Type of element to return

Parameters:

list - Typed list passed into method. Cannot be null.

Returns:

the get(0) element in the list. If there are no elements, return null.

Throws:

OperationFailedException

getOptionalZeroElement

public static <T> T getOptionalZeroElement(List<T> list,
                           boolean throwOnNullList)
                                throws OperationFailedException

Cardinality of zero or one. Will return the value or null depending on what's in the list. List has 1 element, return element. List has 0 elements, return null. else throw exception. This is a generic method so you will not need to worry about casting when using this method Using get(0) in a non-test class will result in a critical sonar issue being reported which will result in a JIRA issue. Correcting get(0) depends on the cardinality constraints on the list. If a list constraint is changed, get(0) might not be the right answer anymore and we would prefer to expose that problem at the source rather than requiring implementers to track down the cardinality constraint enforcement in java. This is handled via OperationFailedException being thrown in the examples belowCardinality of one and only one element:

Type Parameters:

T - Type of element to return

Parameters:

list - Typed list passed into method.

throwOnNullList - true if an OperationFailedException should be thrown if the list is null. If false it will allow null to be returned in the list is null case.

throwOnEmptyList - true if an OperationFailedException should be thrown if the list is empty. If false it will allow null to be returned in the list is empty case.

Returns:

the get(0) element in the list. If there are no elements, return null.

Throws:

OperationFailedException

areCollectionContentsEqual

public static <T> boolean areCollectionContentsEqual(Collection<T> source,
                                     Collection<T> target)

A Null-safe test of the contents of each list that returns true if they are identical using bag semantics.

With the same collection size and the frequency of values are equal between the collections.

The type T needs to implement Object.hashCode and Object.equals since we need to compute the frequency of each occurrence in the collection using a java.util.Map.

Parameters:

source - the first collection in the comparison

target - the second collection in the comparison

Returns:

true if the source and target list are of the same size and each element within them are equal.