jadex.commons.collection

Class NestedMap

java.lang.Object

jadex.commons.collection.NestedMap

All Implemented Interfaces:

Serializable, Map

public class NestedMap
extends Object
implements Map, Serializable

A nested map refers to parent maps for entries not found in this map. Modifications of this map do not affect the parent maps.

See Also:

Serialized Form

Nested Class Summary

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

Map.Entry<K,V>

Constructor Summary

Constructors

Constructor and Description
NestedMap(Map parent) Create a nested map, referring to the specified parent map.
NestedMap(Map[] parents) Create a nested map, referring to the specified parent maps.

Method Summary

Modifier and Type	Method and Description
void	clear() Removes all mappings from this map (optional operation).
boolean	containsKey(Object key) Returns true if this map contains a mapping for the specified key.
boolean	containsValue(Object value) Returns true if this map maps one or more keys to the specified value.
Set	entrySet() Returns a set view of the mappings contained in this map.
boolean	equals(Object o) Compares the specified object with this map for equality.
Object	get(Object key) Returns the value to which this map maps the specified key.
Map	getLocalMap() Get the map containing the local mappings.
int	hashCode() Returns the hash code value for this map.
boolean	isEmpty() Returns true if this map contains no key-value mappings.
Set	keySet() Returns a set view of the keys contained in this map.
Object	put(Object key, Object value) Associates the specified value with the specified key in this map (optional operation).
void	putAll(Map t) Copies all of the mappings from the specified map to this map (optional operation).
Object	remove(Object key) Removes the mapping for this key from this map if it is present (optional operation).
int	size() Returns the number of key-value mappings in this map.
String	toString() Create a string representation of this map.
Collection	values() Returns a collection view of the values contained in this map.

Methods inherited from class java.lang.Object

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

NestedMap

public NestedMap(Map parent)

Create a nested map, referring to the specified parent map.

Parameters:

parent - The parent map.

NestedMap

public NestedMap(Map[] parents)

Create a nested map, referring to the specified parent maps.

Parameters:

parents - The parent maps.

Method Detail

getLocalMap

public Map getLocalMap()

Get the map containing the local mappings.

size

public int size()

Returns the number of key-value mappings in this map. If the map contains more than Integer.MAX_VALUE elements, returns Integer.MAX_VALUE. Note, complexity of the implementation is not constant but linear to the number of entries in the contained maps!

Specified by:

size in interface Map

Returns:

the number of key-value mappings in this map.

isEmpty

public boolean isEmpty()

Returns true if this map contains no key-value mappings.

Specified by:

isEmpty in interface Map

Returns:

true if this map contains no key-value mappings.

containsKey

public boolean containsKey(Object key)

Returns true if this map contains a mapping for the specified key. More formally, returns true if and only if this map contains at a mapping for a key k such that (key==null ? k==null : key.equals(k)). (There can be at most one such mapping.)

Specified by:

containsKey in interface Map

Parameters:

key - key whose presence in this map is to be tested.

Returns:

true if this map contains a mapping for the specified key.

Throws:

ClassCastException - if the key is of an inappropriate type for this map (optional).

NullPointerException - if the key is null and this map does not not permit null keys (optional).

containsValue

public boolean containsValue(Object value)

Returns true if this map maps one or more keys to the specified value. More formally, returns true if and only if this map contains at least one mapping to a value v such that (value==null ? v==null : value.equals(v)). This operation will probably require time linear in the map size for most implementations of the Map interface.

Specified by:

containsValue in interface Map

Parameters:

value - value whose presence in this map is to be tested.

Returns:

true if this map maps one or more keys to the specified value.

Throws:

ClassCastException - if the value is of an inappropriate type for this map (optional).

NullPointerException - if the value is null and this map does not not permit null values (optional).

get

public Object get(Object key)

Returns the value to which this map maps the specified key. Returns null if the map contains no mapping for this key. A return value of null does not necessarily indicate that the map contains no mapping for the key; it's also possible that the map explicitly maps the key to null. The containsKey operation may be used to distinguish these two cases.

More formally, if this map contains a mapping from a key k to a value v such that (key==null ? k==null : key.equals(k)), then this method returns v; otherwise it returns null. (There can be at most one such mapping.)

Specified by:

get in interface Map

Parameters:

key - key whose associated value is to be returned.

Returns:

the value to which this map maps the specified key, or null if the map contains no mapping for this key.

Throws:

ClassCastException - if the key is of an inappropriate type for this map (optional).

NullPointerException - key is null and this map does not not permit null keys (optional).

See Also:

containsKey(Object)

put

public Object put(Object key,
                  Object value)

Associates the specified value with the specified key in this map (optional operation). If the map previously contained a mapping for this key, the old value is replaced by the specified value. (A map m is said to contain a mapping for a key k if and only if m.containsKey(k) would return true.))

Specified by:

put in interface Map

Parameters:

key - key with which the specified value is to be associated.

value - value to be associated with the specified key.

Returns:

previous value associated with specified key, or null if there was no mapping for key. A null return can also indicate that the map previously associated null with the specified key, if the implementation supports null values.

Throws:

UnsupportedOperationException - if the put operation is not supported by this map.

ClassCastException - if the class of the specified key or value prevents it from being stored in this map.

IllegalArgumentException - if some aspect of this key or value prevents it from being stored in this map.

NullPointerException - this map does not permit null keys or values, and the specified key or value is null.

remove

public Object remove(Object key)

Removes the mapping for this key from this map if it is present (optional operation). More formally, if this map contains a mapping from key k to value v such that (key==null ? k==null : key.equals(k)), that mapping is removed. (The map can contain at most one such mapping.)

Returns the value to which the map previously associated the key, or null if the map contained no mapping for this key. (A null return can also indicate that the map previously associated null with the specified key if the implementation supports null values.) The map will not contain a mapping for the specified key once the call returns.

Specified by:

remove in interface Map

Parameters:

key - key whose mapping is to be removed from the map.

Returns:

previous value associated with specified key, or null if there was no mapping for key.

Throws:

ClassCastException - if the key is of an inappropriate type for this map (optional).

NullPointerException - if the key is null and this map does not not permit null keys (optional).

UnsupportedOperationException - if the remove method is not supported by this map.

putAll

public void putAll(Map t)

Copies all of the mappings from the specified map to this map (optional operation). The effect of this call is equivalent to that of calling put(k, v) on this map once for each mapping from key k to value v in the specified map. The behavior of this operation is unspecified if the specified map is modified while the operation is in progress.

Specified by:

putAll in interface Map

Parameters:

t - Mappings to be stored in this map.

Throws:

UnsupportedOperationException - if the putAll method is not supported by this map.

ClassCastException - if the class of a key or value in the specified map prevents it from being stored in this map.

IllegalArgumentException - some aspect of a key or value in the specified map prevents it from being stored in this map.

NullPointerException - the specified map is null, or if this map does not permit null keys or values, and the specified map contains null keys or values.

clear

public void clear()

Removes all mappings from this map (optional operation).

Specified by:

clear in interface Map

Throws:

UnsupportedOperationException - if clear is not supported by this map.

keySet

public Set keySet()

Returns a set view of the keys contained in this map. The set is backed by the map, so changes to the map are reflected in the set, and vice-versa. If the map is modified while an iteration over the set is in progress, the results of the iteration are undefined. The set supports element removal, which removes the corresponding mapping from the map, via the Iterator.remove, Set.remove, removeAll retainAll, and clear operations. It does not support the add or addAll operations.

Specified by:

keySet in interface Map

Returns:

a set view of the keys contained in this map.

values

public Collection values()

Returns a collection view of the values contained in this map. The collection is backed by the map, so changes to the map are reflected in the collection, and vice-versa. If the map is modified while an iteration over the collection is in progress, the results of the iteration are undefined. The collection supports element removal, which removes the corresponding mapping from the map, via the Iterator.remove, Collection.remove, removeAll, retainAll and clear operations. It does not support the add or addAll operations.

Specified by:

values in interface Map

Returns:

a collection view of the values contained in this map.

entrySet

public Set entrySet()

Returns a set view of the mappings contained in this map. Each element in the returned set is a Map.Entry. The set is backed by the map, so changes to the map are reflected in the set, and vice-versa. If the map is modified while an iteration over the set is in progress, the results of the iteration are undefined. The set supports element removal, which removes the corresponding mapping from the map, via the Iterator.remove, Set.remove, removeAll, retainAll and clear operations. It does not support the add or addAll operations.

Specified by:

entrySet in interface Map

Returns:

a set view of the mappings contained in this map.

equals

public boolean equals(Object o)

Compares the specified object with this map for equality. Returns true if the given object is also a map and the two Maps represent the same mappings. More formally, two maps t1 and t2 represent the same mappings if t1.entrySet().equals(t2.entrySet()). This ensures that the equals method works properly across different implementations of the Map interface.

Specified by:

equals in interface Map

Overrides:

equals in class Object

Parameters:

o - object to be compared for equality with this map.

Returns:

true if the specified object is equal to this map.

hashCode

public int hashCode()

Returns the hash code value for this map. The hash code of a map is defined to be the sum of the hashCodes of each entry in the map's entrySet view. This ensures that t1.equals(t2) implies that t1.hashCode()==t2.hashCode() for any two maps t1 and t2, as required by the general contract of Object.hashCode.

Specified by:

hashCode in interface Map

Overrides:

hashCode in class Object

Returns:

the hash code value for this map.

See Also:

Object.hashCode(), Object.equals(Object), equals(Object)

toString

public String toString()

Create a string representation of this map.

Overrides:

toString in class Object