Package org.apache.commons.collections.map

Class AbstractInputCheckedMapDecorator

java.lang.Object

org.apache.commons.collections.map.AbstractMapDecorator

org.apache.commons.collections.map.AbstractInputCheckedMapDecorator

All Implemented Interfaces:

java.util.Map

Direct Known Subclasses:

PredicatedMap, TransformedMap

abstract class AbstractInputCheckedMapDecorator
extends AbstractMapDecorator

An abstract base class that simplifies the task of creating map decorators.

The Map API is very difficult to decorate correctly, and involves implementing lots of different classes. This class exists to provide a simpler API.

Special hook methods are provided that are called when objects are added to the map. By overriding these methods, the input can be validated or manipulated. In addition to the main map methods, the entrySet is also affected, which is the hardest part of writing map implementations.

This class is package-scoped, and may be withdrawn or replaced in future versions of Commons Collections.

Since:

Commons Collections 3.1

Version:

$Revision: 646777 $ $Date: 2008-04-10 14:33:15 +0200 (Thu, 10 Apr 2008) $

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
(package private) static class	AbstractInputCheckedMapDecorator.EntrySet	Implementation of an entry set that checks additions via setValue.
(package private) static class	AbstractInputCheckedMapDecorator.EntrySetIterator	Implementation of an entry set iterator that checks additions via setValue.
(package private) static class	AbstractInputCheckedMapDecorator.MapEntry	Implementation of a map entry that checks additions via setValue.

Nested classes/interfaces inherited from interface java.util.Map

java.util.Map.Entry<K extends java.lang.Object,V extends java.lang.Object>

Field Summary

Fields inherited from class org.apache.commons.collections.map.AbstractMapDecorator

map

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	AbstractInputCheckedMapDecorator()	Constructor only used in deserialization, do not use otherwise.
protected	AbstractInputCheckedMapDecorator(java.util.Map map)	Constructor that wraps (not copies).

Method Summary

Modifier and Type	Method	Description
protected abstract java.lang.Object	checkSetValue(java.lang.Object value)	Hook method called when a value is being set using setValue.
java.util.Set	entrySet()
protected boolean	isSetValueChecking()	Hook method called to determine if checkSetValue has any effect.

Methods inherited from class org.apache.commons.collections.map.AbstractMapDecorator

clear, containsKey, containsValue, equals, get, getMap, hashCode, isEmpty, keySet, put, putAll, remove, size, toString, values

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface java.util.Map

compute, computeIfAbsent, computeIfPresent, forEach, getOrDefault, merge, putIfAbsent, remove, replace, replace, replaceAll

Constructor Detail

AbstractInputCheckedMapDecorator

protected AbstractInputCheckedMapDecorator()

Constructor only used in deserialization, do not use otherwise.

AbstractInputCheckedMapDecorator

protected AbstractInputCheckedMapDecorator(java.util.Map map)

Constructor that wraps (not copies).

Parameters:

map - the map to decorate, must not be null

Throws:

java.lang.IllegalArgumentException - if map is null

Method Detail

checkSetValue

protected abstract java.lang.Object checkSetValue(java.lang.Object value)

Hook method called when a value is being set using setValue.

An implementation may validate the value and throw an exception or it may transform the value into another object.

This implementation returns the input value.

Parameters:

value - the value to check

Throws:

java.lang.UnsupportedOperationException - if the map may not be changed by setValue

java.lang.IllegalArgumentException - if the specified value is invalid

java.lang.ClassCastException - if the class of the specified value is invalid

java.lang.NullPointerException - if the specified value is null and nulls are invalid

isSetValueChecking

protected boolean isSetValueChecking()

Hook method called to determine if checkSetValue has any effect.

An implementation should return false if the checkSetValue method has no effect as this optimises the implementation.

This implementation returns true.

Returns:

true always

entrySet

public java.util.Set entrySet()

Specified by:

entrySet in interface java.util.Map

Overrides:

entrySet in class AbstractMapDecorator