org.springframework.core

Class AttributeAccessorSupport

java.lang.Object

org.springframework.core.AttributeAccessorSupport

All Implemented Interfaces:

Serializable, AttributeAccessor

Direct Known Subclasses:

BeanMetadataAttributeAccessor

public abstract class AttributeAccessorSupport
extends Object
implements AttributeAccessor, Serializable

Support class for AttributeAccessors, providing a base implementation of all methods. To be extended by subclasses.

Serializable if subclasses and all attribute values are Serializable.

Since:

2.0

Author:

Rob Harrop, Juergen Hoeller, Sam Brannen

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
AttributeAccessorSupport()

Method Summary

Modifier and Type	Method and Description
String[]	attributeNames() Return the names of all attributes.
<T> T	computeAttribute(String name, Function<String,T> computeFunction) Compute a new value for the attribute identified by name if necessary and set the new value in this AttributeAccessor.
protected void	copyAttributesFrom(AttributeAccessor source) Copy the attributes from the supplied AttributeAccessor to this accessor.
boolean	equals(Object other)
Object	getAttribute(String name) Get the value of the attribute identified by name.
boolean	hasAttribute(String name) Return true if the attribute identified by name exists.
int	hashCode()
Object	removeAttribute(String name) Remove the attribute identified by name and return its value.
void	setAttribute(String name, Object value) Set the attribute defined by name to the supplied value.

Methods inherited from class java.lang.Object

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

Constructor Detail

AttributeAccessorSupport

public AttributeAccessorSupport()

Method Detail

setAttribute

public void setAttribute(String name,
                         @Nullable
                         Object value)

Description copied from interface: AttributeAccessor

Set the attribute defined by name to the supplied value.

If value is null, the attribute is removed.

In general, users should take care to prevent overlaps with other metadata attributes by using fully-qualified names, perhaps using class or package names as prefix.

Specified by:

setAttribute in interface AttributeAccessor

Parameters:

name - the unique attribute key

value - the attribute value to be attached

getAttribute

@Nullable
public Object getAttribute(String name)

Description copied from interface: AttributeAccessor

Get the value of the attribute identified by name.

Return null if the attribute doesn't exist.

Specified by:

getAttribute in interface AttributeAccessor

Parameters:

name - the unique attribute key

Returns:

the current value of the attribute, if any

computeAttribute

public <T> T computeAttribute(String name,
                              Function<String,T> computeFunction)

Description copied from interface: AttributeAccessor

Compute a new value for the attribute identified by name if necessary and set the new value in this AttributeAccessor.

If a value for the attribute identified by name already exists in this AttributeAccessor, the existing value will be returned without applying the supplied compute function.

The default implementation of this method is not thread safe but can be overridden by concrete implementations of this interface.

Specified by:

computeAttribute in interface AttributeAccessor

Type Parameters:

T - the type of the attribute value

Parameters:

name - the unique attribute key

computeFunction - a function that computes a new value for the attribute name; the function must not return a null value

Returns:

the existing value or newly computed value for the named attribute

See Also:

AttributeAccessor.getAttribute(String), AttributeAccessor.setAttribute(String, Object)

removeAttribute

@Nullable
public Object removeAttribute(String name)

Description copied from interface: AttributeAccessor

Remove the attribute identified by name and return its value.

Return null if no attribute under name is found.

Specified by:

removeAttribute in interface AttributeAccessor

Parameters:

name - the unique attribute key

Returns:

the last value of the attribute, if any

hasAttribute

public boolean hasAttribute(String name)

Description copied from interface: AttributeAccessor

Return true if the attribute identified by name exists.

Otherwise return false.

Specified by:

hasAttribute in interface AttributeAccessor

Parameters:

name - the unique attribute key

attributeNames

public String[] attributeNames()

Description copied from interface: AttributeAccessor

Return the names of all attributes.

Specified by:

attributeNames in interface AttributeAccessor

copyAttributesFrom

protected void copyAttributesFrom(AttributeAccessor source)

Copy the attributes from the supplied AttributeAccessor to this accessor.

Parameters:

source - the AttributeAccessor to copy from

equals

public boolean equals(@Nullable
                      Object other)

Overrides:

equals in class Object

hashCode

public int hashCode()

Overrides:

hashCode in class Object