ch.agent.crnickl.impl

Class AttributeImpl<T>

java.lang.Object

ch.agent.crnickl.impl.AttributeImpl<T>

Type Parameters:

T - the underlying data type of the attribute

All Implemented Interfaces:

Attribute<T>

public class AttributeImpl<T>
extends Object
implements Attribute<T>

Default implementation of Attribute.

Author:

Jean-Paul Vetterli

Constructor Summary

Constructors

Constructor and Description
AttributeImpl(AttributeDefinitionImpl<T> attributeDefinition) Construct an Attribute.

Method Summary

Modifier and Type	Method and Description
boolean	equals(Object obj)
T	get() Return the attribute's value.
String	getDescription(boolean effective) Return the description of the attribute's value.
Property<T>	getProperty() Return the attribute's Property.
int	hashCode()
void	reset() Reset the default value of the attribute.
void	scan(Object value) Set the value of the attribute from an Object.
void	set(T value) Set the value of the attribute.
void	setDescription(String description) Set the description of the current attribute value.
String	toString()
<S> Attribute<S>	typeCheck(Class<S> type) Cast the attribute to the type specified.

Methods inherited from class java.lang.Object

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

Constructor Detail

AttributeImpl

public AttributeImpl(AttributeDefinitionImpl<T> attributeDefinition)

Construct an Attribute.

Parameters:

attributeDefinition - an attribute definition

Method Detail

getProperty

public Property<T> getProperty()

Description copied from interface: Attribute

Return the attribute's Property.

Specified by:

getProperty in interface Attribute<T>

Returns:

the property of the attribute

get

public T get()

Description copied from interface: Attribute

Return the attribute's value. This value is either the default value, taken from the AttributeDefinition, or the value set with Attribute.set(T) or Attribute.scan(java.lang.Object).

Specified by:

get in interface Attribute<T>

Returns:

the value of the attribute

reset

public void reset()

Description copied from interface: Attribute

Reset the default value of the attribute. This removes the current value of the attribute with the consequence that the current default value taken from the AttributeDefinition will apply.

Note

When an attribute value happens to be equal to the default value but should not change when the default is updated, it must be set explicitly.

Specified by:

reset in interface Attribute<T>

set

public void set(T value)
         throws T2DBException

Description copied from interface: Attribute

Set the value of the attribute. The value must agree with the AttributeDefinition, as enforced by Property.check(Object). Setting the value to null has the same effect as calling Attribute.reset().

Specified by:

set in interface Attribute<T>

Parameters:

value - a value for the attribute

Throws:

T2DBException

scan

public void scan(Object value)
          throws T2DBException

Description copied from interface: Attribute

Set the value of the attribute from an Object. A null value is passed directly to Attribute.set(Object). When not null, the value either must be assignment compatible with the underlying type of the attribute or it must be a string. In the first case it is cast and passed to Attribute.set(Object). In the second case it is scanned by ValueType.scan(String) before being passed to Attribute.set(Object).

Specified by:

scan in interface Attribute<T>

Parameters:

value - an object representing the new value of the attribute

Throws:

T2DBException

getDescription

public String getDescription(boolean effective)

Description copied from interface: Attribute

Return the description of the attribute's value. When the effective parameter is set, and there is no description, and the attribute value is from a value list, return the description from the value list, if any.

Specified by:

getDescription in interface Attribute<T>

Parameters:

effective - if true fall back to description from definition

Returns:

a description of the current attribute value

setDescription

public void setDescription(String description)

Description copied from interface: Attribute

Set the description of the current attribute value.

Specified by:

setDescription in interface Attribute<T>

Parameters:

description - a description for the current attribute value

typeCheck

public <S> Attribute<S> typeCheck(Class<S> type)
                           throws T2DBException

Description copied from interface: Attribute

Cast the attribute to the type specified. The method performs type checking at run time and allows to catch type errors in controlled fashion.

Specified by:

typeCheck in interface Attribute<T>

Parameters:

type - the underlying type required

Returns:

the attribute cast to the type specified

Throws:

T2DBException

hashCode

public int hashCode()

Overrides:

hashCode in class Object

equals

public boolean equals(Object obj)

Overrides:

equals in class Object

toString

public String toString()

Overrides:

toString in class Object