org.springframework.binding.collection

Class MapAccessor<K,V>

java.lang.Object

org.springframework.binding.collection.MapAccessor<K,V>

All Implemented Interfaces:

MapAdaptable<K,V>

public class MapAccessor<K,V>
extends java.lang.Object
implements MapAdaptable<K,V>

A simple, generic decorator for getting attributes out of a map. May be instantiated directly or used as a base class as a convenience.

Author:

Keith Donald

Constructor Summary

Constructors

Constructor and Description
MapAccessor(java.util.Map<K,V> map) Creates a new attribute map accessor.

Method Summary

Methods

Modifier and Type	Method and Description
java.util.Map<K,V>	asMap() Returns this object's contents as a Map.
void	assertContainsKey(java.lang.Object key) Asserts that the attribute is present in the attribute map.
<T> T	assertKeyValueInstanceOf(java.lang.Object key, java.lang.Object value, java.lang.Class<T> requiredType) Assert that the key value, if non null, is an instance of the required type.
<T> T	assertKeyValueOfType(java.lang.Object key, java.lang.Class<T> requiredType) Assert that value of the map key, if non-null, is of the required type.
boolean	containsKey(java.lang.Object key, java.lang.Class<?> requiredType) Indicates if the attribute is present in the attribute map and of the required type.
V	get(java.lang.Object key) Returns a value in the map, returning null if the attribute is not present.
<T extends V> T	get(java.lang.Object key, java.lang.Class<T> requiredType) Returns a value in the map, asserting it is of the required type if present and returning null if not found.
<T extends V> T	get(java.lang.Object key, java.lang.Class<T> requiredType, T defaultValue) Returns a value in the map of the specified type, returning the defaultValue if no value is found.
V	get(java.lang.Object key, V defaultValue) Returns a value in the map, returning the defaultValue if no value was found.
<T extends V> T[]	getArray(java.lang.Object key, java.lang.Class<? extends T[]> requiredType) Returns a array value in the map, asserting it is of the required type if present and returning null if not found.
java.lang.Boolean	getBoolean(java.lang.Object key) Returns a boolean value in the map, returning null if no value was found.
java.lang.Boolean	getBoolean(java.lang.Object key, java.lang.Boolean defaultValue) Returns a boolean value in the map, returning the defaultValue if no value was found.
java.util.Collection<V>	getCollection(java.lang.Object key) Returns a collection value in the map, returning null if no value was found.
<T extends java.util.Collection<V>> T	getCollection(java.lang.Object key, java.lang.Class<T> requiredType) Returns a collection value in the map, asserting it is of the required type if present and returning null if not found.
java.lang.Integer	getInteger(java.lang.Object key) Returns an integer value in the map, returning null if no value was found.
java.lang.Integer	getInteger(java.lang.Object key, java.lang.Integer defaultValue) Returns an integer value in the map, returning the defaultValue if no value was found.
java.lang.Long	getLong(java.lang.Object key) Returns a long value in the map, returning null if no value was found.
java.lang.Long	getLong(java.lang.Object key, java.lang.Long defaultValue) Returns a long value in the map, returning the defaultValue if no value was found.
<T extends java.lang.Number> T	getNumber(java.lang.Object key, java.lang.Class<T> requiredType) Returns a number value in the map that is of the specified type, returning null if no value was found.
<T extends java.lang.Number> T	getNumber(java.lang.Object key, java.lang.Class<T> requiredType, T defaultValue) Returns a number attribute value in the map of the specified type, returning the defaultValue if no value was found.
V	getRequired(java.lang.Object key) Returns a value in the map, throwing an exception if the attribute is not present and of the correct type.
<T extends V> T	getRequired(java.lang.Object key, java.lang.Class<T> requiredType) Returns an value in the map, asserting it is present and of the required type.
<T extends V> T[]	getRequiredArray(java.lang.Object key, java.lang.Class<? extends T[]> requiredType) Returns an array value in the map, asserting it is of the required type if present and throwing an exception if not found.
java.lang.Boolean	getRequiredBoolean(java.lang.Object key) Returns a boolean value in the map, throwing an exception if the value is not present and of the correct type.
java.util.Collection<V>	getRequiredCollection(java.lang.Object key) Returns a collection value in the map, throwing an exception if not found.
<T extends java.util.Collection<V>> T	getRequiredCollection(java.lang.Object key, java.lang.Class<T> requiredType) Returns a collection value in the map, asserting it is of the required type if present and throwing an exception if not found.
java.lang.Integer	getRequiredInteger(java.lang.Object key) Returns an integer value in the map, throwing an exception if the value is not present and of the correct type.
java.lang.Long	getRequiredLong(java.lang.Object key) Returns a long value in the map, throwing an exception if the value is not present and of the correct type.
<T extends java.lang.Number> T	getRequiredNumber(java.lang.Object key, java.lang.Class<T> requiredType) Returns a number value in the map, throwing an exception if the attribute is not present and of the correct type.
java.lang.String	getRequiredString(java.lang.Object key) Returns a string value in the map, throwing an exception if the attribute is not present and of the correct type.
java.lang.String	getString(java.lang.Object key) Returns a string value in the map, returning null if no value was found.
java.lang.String	getString(java.lang.Object key, java.lang.String defaultValue) Returns a string value in the map, returning the defaultValue if no value was found.

Methods inherited from class java.lang.Object

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

Constructor Detail

MapAccessor

public MapAccessor(java.util.Map<K,V> map)

Creates a new attribute map accessor.

Parameters:

map - the map

Method Detail

asMap

public java.util.Map<K,V> asMap()

Description copied from interface: MapAdaptable

Returns this object's contents as a Map. The returned map may or may not be modifiable depending on this implementation.

Warning: this operation may be called frequently; if so care should be taken so that the map contents (if calculated) be cached as appropriate.

Specified by:

asMap in interface MapAdaptable<K,V>

Returns:

the object's contents as a map

get

public V get(java.lang.Object key)

Returns a value in the map, returning null if the attribute is not present.

Parameters:

key - the key

Returns:

the value

get

public V get(java.lang.Object key,
    V defaultValue)

Returns a value in the map, returning the defaultValue if no value was found.

Parameters:

key - the key

defaultValue - the default

Returns:

the attribute value

get

public <T extends V> T get(java.lang.Object key,
                  java.lang.Class<T> requiredType)
                throws java.lang.IllegalArgumentException

Returns a value in the map, asserting it is of the required type if present and returning null if not found.

Parameters:

key - the key

requiredType - the required type

Returns:

the value

Throws:

java.lang.IllegalArgumentException - if the key is present but the value is not of the required type

get

public <T extends V> T get(java.lang.Object key,
                  java.lang.Class<T> requiredType,
                  T defaultValue)

Returns a value in the map of the specified type, returning the defaultValue if no value is found.

Parameters:

key - the key

requiredType - the required type

defaultValue - the default

Returns:

the attribute value

Throws:

java.lang.IllegalArgumentException - if the key is present but the value is not of the required type

getRequired

public V getRequired(java.lang.Object key)
              throws java.lang.IllegalArgumentException

Returns a value in the map, throwing an exception if the attribute is not present and of the correct type.

Parameters:

key - the key

Returns:

the value

Throws:

java.lang.IllegalArgumentException

getRequired

public <T extends V> T getRequired(java.lang.Object key,
                          java.lang.Class<T> requiredType)
                        throws java.lang.IllegalArgumentException

Returns an value in the map, asserting it is present and of the required type.

Parameters:

key - the key

requiredType - the required type

Returns:

the value

Throws:

java.lang.IllegalArgumentException

getString

public java.lang.String getString(java.lang.Object key)
                           throws java.lang.IllegalArgumentException

Returns a string value in the map, returning null if no value was found.

Parameters:

key - the key

Returns:

the string value

Throws:

java.lang.IllegalArgumentException - if the key is present but the value is not a string

getString

public java.lang.String getString(java.lang.Object key,
                         java.lang.String defaultValue)
                           throws java.lang.IllegalArgumentException

Returns a string value in the map, returning the defaultValue if no value was found.

Parameters:

key - the key

defaultValue - the default

Returns:

the string value

Throws:

java.lang.IllegalArgumentException - if the key is present but the value is not a string

getRequiredString

public java.lang.String getRequiredString(java.lang.Object key)
                                   throws java.lang.IllegalArgumentException

Returns a string value in the map, throwing an exception if the attribute is not present and of the correct type.

Parameters:

key - the key

Returns:

the string value

Throws:

java.lang.IllegalArgumentException - if the key is not present or present but the value is not a string

getCollection

public java.util.Collection<V> getCollection(java.lang.Object key)
                                      throws java.lang.IllegalArgumentException

Returns a collection value in the map, returning null if no value was found.

Parameters:

key - the key

Returns:

the collection value

Throws:

java.lang.IllegalArgumentException - if the key is present but the value is not a collection

getCollection

public <T extends java.util.Collection<V>> T getCollection(java.lang.Object key,
                                                  java.lang.Class<T> requiredType)
                                             throws java.lang.IllegalArgumentException

Returns a collection value in the map, asserting it is of the required type if present and returning null if not found.

Parameters:

key - the key

Returns:

the collection value

Throws:

java.lang.IllegalArgumentException - if the key is present but the value is not a collection

getRequiredCollection

public java.util.Collection<V> getRequiredCollection(java.lang.Object key)
                                              throws java.lang.IllegalArgumentException

Returns a collection value in the map, throwing an exception if not found.

Parameters:

key - the key

Returns:

the collection value

Throws:

java.lang.IllegalArgumentException - if the key is not present or present but the value is not a collection

getRequiredCollection

public <T extends java.util.Collection<V>> T getRequiredCollection(java.lang.Object key,
                                                          java.lang.Class<T> requiredType)
                                                     throws java.lang.IllegalArgumentException

Returns a collection value in the map, asserting it is of the required type if present and throwing an exception if not found.

Parameters:

key - the key

Returns:

the collection value

Throws:

java.lang.IllegalArgumentException - if the key is not present or present but the value is not a collection of the required type

getArray

public <T extends V> T[] getArray(java.lang.Object key,
                         java.lang.Class<? extends T[]> requiredType)
                       throws java.lang.IllegalArgumentException

Returns a array value in the map, asserting it is of the required type if present and returning null if not found.

Parameters:

key - the key

Returns:

the array value

Throws:

java.lang.IllegalArgumentException - if the key is present but the value is not an array of the required type

getRequiredArray

public <T extends V> T[] getRequiredArray(java.lang.Object key,
                                 java.lang.Class<? extends T[]> requiredType)
                               throws java.lang.IllegalArgumentException

Returns an array value in the map, asserting it is of the required type if present and throwing an exception if not found.

Parameters:

key - the key

Returns:

the array value

Throws:

java.lang.IllegalArgumentException - if the key is not present or present but the value is not a array of the required type

getNumber

public <T extends java.lang.Number> T getNumber(java.lang.Object key,
                                       java.lang.Class<T> requiredType)
                                     throws java.lang.IllegalArgumentException

Returns a number value in the map that is of the specified type, returning null if no value was found.

Parameters:

key - the key

requiredType - the required number type

Returns:

the number value

Throws:

java.lang.IllegalArgumentException - if the key is present but the value is not a number of the required type

getNumber

public <T extends java.lang.Number> T getNumber(java.lang.Object key,
                                       java.lang.Class<T> requiredType,
                                       T defaultValue)
                                     throws java.lang.IllegalArgumentException

Returns a number attribute value in the map of the specified type, returning the defaultValue if no value was found.

Parameters:

key - the attribute name

defaultValue - the default

Returns:

the number value

Throws:

java.lang.IllegalArgumentException - if the key is present but the value is not a number of the required type

getRequiredNumber

public <T extends java.lang.Number> T getRequiredNumber(java.lang.Object key,
                                               java.lang.Class<T> requiredType)
                                             throws java.lang.IllegalArgumentException

Returns a number value in the map, throwing an exception if the attribute is not present and of the correct type.

Parameters:

key - the key

Returns:

the number value

Throws:

java.lang.IllegalArgumentException - if the key is not present or present but the value is not a number of the required type

getInteger

public java.lang.Integer getInteger(java.lang.Object key)
                             throws java.lang.IllegalArgumentException

Returns an integer value in the map, returning null if no value was found.

Parameters:

key - the key

Returns:

the integer value

Throws:

java.lang.IllegalArgumentException - if the key is present but the value is not an integer

getInteger

public java.lang.Integer getInteger(java.lang.Object key,
                           java.lang.Integer defaultValue)
                             throws java.lang.IllegalArgumentException

Returns an integer value in the map, returning the defaultValue if no value was found.

Parameters:

key - the key

defaultValue - the default

Returns:

the integer value

Throws:

java.lang.IllegalArgumentException - if the key is present but the value is not an integer

getRequiredInteger

public java.lang.Integer getRequiredInteger(java.lang.Object key)
                                     throws java.lang.IllegalArgumentException

Returns an integer value in the map, throwing an exception if the value is not present and of the correct type.

Parameters:

key - the attribute name

Returns:

the integer attribute value

Throws:

java.lang.IllegalArgumentException - if the key is not present or present but the value is not an integer

getLong

public java.lang.Long getLong(java.lang.Object key)
                       throws java.lang.IllegalArgumentException

Returns a long value in the map, returning null if no value was found.

Parameters:

key - the key

Returns:

the long value

Throws:

java.lang.IllegalArgumentException - if the key is present but not a long

getLong

public java.lang.Long getLong(java.lang.Object key,
                     java.lang.Long defaultValue)
                       throws java.lang.IllegalArgumentException

Returns a long value in the map, returning the defaultValue if no value was found.

Parameters:

key - the key

defaultValue - the default

Returns:

the long attribute value

Throws:

java.lang.IllegalArgumentException - if the key is present but the value is not a long

getRequiredLong

public java.lang.Long getRequiredLong(java.lang.Object key)
                               throws java.lang.IllegalArgumentException

Returns a long value in the map, throwing an exception if the value is not present and of the correct type.

Parameters:

key - the key

Returns:

the long attribute value

Throws:

java.lang.IllegalArgumentException - if the key is not present or present but the value is not a long

getBoolean

public java.lang.Boolean getBoolean(java.lang.Object key)
                             throws java.lang.IllegalArgumentException

Returns a boolean value in the map, returning null if no value was found.

Parameters:

key - the key

Returns:

the boolean value

Throws:

java.lang.IllegalArgumentException - if the key is present but the value is not a boolean

getBoolean

public java.lang.Boolean getBoolean(java.lang.Object key,
                           java.lang.Boolean defaultValue)
                             throws java.lang.IllegalArgumentException

Returns a boolean value in the map, returning the defaultValue if no value was found.

Parameters:

key - the key

defaultValue - the default

Returns:

the boolean value

Throws:

java.lang.IllegalArgumentException - if the key is present but the value is not a boolean

getRequiredBoolean

public java.lang.Boolean getRequiredBoolean(java.lang.Object key)
                                     throws java.lang.IllegalArgumentException

Returns a boolean value in the map, throwing an exception if the value is not present and of the correct type.

Parameters:

key - the attribute

Returns:

the boolean value

Throws:

java.lang.IllegalArgumentException - if the key is not present or present but the value is not a boolean

assertContainsKey

public void assertContainsKey(java.lang.Object key)
                       throws java.lang.IllegalArgumentException

Asserts that the attribute is present in the attribute map.

Parameters:

key - the key

Throws:

java.lang.IllegalArgumentException - if the key is not present

containsKey

public boolean containsKey(java.lang.Object key,
                  java.lang.Class<?> requiredType)
                    throws java.lang.IllegalArgumentException

Indicates if the attribute is present in the attribute map and of the required type.

Parameters:

key - the attribute name

Returns:

true if present and of the required type, false if not present.

Throws:

java.lang.IllegalArgumentException

assertKeyValueOfType

public <T> T assertKeyValueOfType(java.lang.Object key,
                         java.lang.Class<T> requiredType)

Assert that value of the map key, if non-null, is of the required type.

Parameters:

key - the attribute name

requiredType - the required attribute value type

Returns:

the attribute value

assertKeyValueInstanceOf

public <T> T assertKeyValueInstanceOf(java.lang.Object key,
                             java.lang.Object value,
                             java.lang.Class<T> requiredType)

Assert that the key value, if non null, is an instance of the required type.

Parameters:

key - the key

value - the value

requiredType - the required type

Returns:

the value