javax.swing.text
Class SimpleAttributeSet.EmptyAttributeSet

java.lang.Object
  javax.swing.text.SimpleAttributeSet.EmptyAttributeSet

All Implemented Interfaces:

AttributeSet, Serializable

Enclosing class:

SimpleAttributeSet

static class SimpleAttributeSet.EmptyAttributeSet

extends Object

implements AttributeSet, Serializable

An AttributeSet this is always empty.

Nested Class Summary

Nested classes inherited from class javax.swing.text.AttributeSet

AttributeSet.CharacterAttribute, AttributeSet.ColorAttribute, AttributeSet.FontAttribute, AttributeSet.ParagraphAttribute

Field Summary

Fields inherited from interface javax.swing.text.AttributeSet

NameAttribute, ResolveAttribute

Constructor Summary

(package private)

SimpleAttributeSet.EmptyAttributeSet()

Method Summary

boolean	containsAttribute(Object name, Object value) Returns true if this set contains this attribute with an equal value.
boolean	containsAttributes(AttributeSet attributes) Returns true if this set contains all the attributes with equal values.
AttributeSet	copyAttributes() Returns an attribute set that is guaranteed not to change over time.
boolean	equals(Object obj) Indicates whether some other object is "equal to" this one.
Object	getAttribute(Object key) Fetches the value of the given attribute.
int	getAttributeCount() Returns the number of attributes contained in this set.
Enumeration	getAttributeNames() Returns an enumeration over the names of the attributes in the set.
AttributeSet	getResolveParent() Gets the resolving parent.
int	hashCode() Returns a hash code value for the object.
boolean	isDefined(Object attrName) Checks whether the named attribute has a value specified in the set without resolving through another attribute set.
boolean	isEqual(AttributeSet attr) Determines if the two attribute sets are equivalent.

Methods inherited from class java.lang.Object

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

Constructor Detail

SimpleAttributeSet.EmptyAttributeSet

SimpleAttributeSet.EmptyAttributeSet()

Method Detail

getAttributeCount

public int getAttributeCount()

Description copied from interface: AttributeSet

Returns the number of attributes contained in this set.

Specified by:

getAttributeCount in interface AttributeSet

Returns:

the number of attributes >= 0

isDefined

public boolean isDefined(Object attrName)

Description copied from interface: AttributeSet

Checks whether the named attribute has a value specified in the set without resolving through another attribute set.

Specified by:

isDefined in interface AttributeSet

Parameters:

attrName - the attribute name

Returns:

true if the attribute has a value specified

isEqual

public boolean isEqual(AttributeSet attr)

Description copied from interface: AttributeSet

Determines if the two attribute sets are equivalent.

Specified by:

isEqual in interface AttributeSet

Parameters:

attr - an attribute set

Returns:

true if the sets are equivalent

copyAttributes

public AttributeSet copyAttributes()

Description copied from interface: AttributeSet

Returns an attribute set that is guaranteed not to change over time.

Specified by:

copyAttributes in interface AttributeSet

Returns:

a copy of the attribute set

getAttribute

public Object getAttribute(Object key)

Description copied from interface: AttributeSet

Fetches the value of the given attribute. If the value is not found locally, the search is continued upward through the resolving parent (if one exists) until the value is either found or there are no more parents. If the value is not found, null is returned.

Specified by:

getAttribute in interface AttributeSet

Parameters:

key - the non-null key of the attribute binding

Returns:

the value

getAttributeNames

public Enumeration getAttributeNames()

Description copied from interface: AttributeSet

Returns an enumeration over the names of the attributes in the set. The values of the Enumeration may be anything and are not constrained to a particular Object type. The set does not include the resolving parent, if one is defined.

Specified by:

getAttributeNames in interface AttributeSet

Returns:

the names

containsAttribute

public boolean containsAttribute(Object name,
                                 Object value)

Description copied from interface: AttributeSet

Returns true if this set contains this attribute with an equal value.

Specified by:

containsAttribute in interface AttributeSet

Parameters:

name - the non-null attribute name

value - the value

Returns:

true if the set contains the attribute with an equal value

containsAttributes

public boolean containsAttributes(AttributeSet attributes)

Description copied from interface: AttributeSet

Returns true if this set contains all the attributes with equal values.

Specified by:

containsAttributes in interface AttributeSet

Parameters:

attributes - the set of attributes to check against

Returns:

true if this set contains all the attributes with equal values

getResolveParent

public AttributeSet getResolveParent()

Description copied from interface: AttributeSet

Gets the resolving parent.

Specified by:

getResolveParent in interface AttributeSet

Returns:

the parent

equals

public boolean equals(Object obj)

Description copied from class: Object

Indicates whether some other object is "equal to" this one.

The equals method implements an equivalence relation on non-null object references:

• It is reflexive: for any non-null reference value x, x.equals(x) should return true.
• It is symmetric: for any non-null reference values x and y, x.equals(y) should return true if and only if y.equals(x) returns true.
• It is transitive: for any non-null reference values x, y, and z, if x.equals(y) returns true and y.equals(z) returns true, then x.equals(z) should return true.
• It is consistent: for any non-null reference values x and y, multiple invocations of x.equals(y) consistently return true or consistently return false, provided no information used in equals comparisons on the objects is modified.
• For any non-null reference value x, x.equals(null) should return false.

The equals method for class Object implements the most discriminating possible equivalence relation on objects; that is, for any non-null reference values x and y, this method returns true if and only if x and y refer to the same object (x == y has the value true).

Note that it is generally necessary to override the hashCode method whenever this method is overridden, so as to maintain the general contract for the hashCode method, which states that equal objects must have equal hash codes.

Overrides:

equals in class Object

Parameters:

obj - the reference object with which to compare.

Returns:

true if this object is the same as the obj argument; false otherwise.

See Also:

Object.hashCode(), Hashtable

hashCode

public int hashCode()

Description copied from class: Object

Returns a hash code value for the object. This method is supported for the benefit of hashtables such as those provided by java.util.Hashtable.

The general contract of hashCode is:

• Whenever it is invoked on the same object more than once during an execution of a Java application, the hashCode method must consistently return the same integer, provided no information used in equals comparisons on the object is modified. This integer need not remain consistent from one execution of an application to another execution of the same application.
• If two objects are equal according to the equals(Object) method, then calling the hashCode method on each of the two objects must produce the same integer result.
• It is not required that if two objects are unequal according to the Object.equals(java.lang.Object) method, then calling the hashCode method on each of the two objects must produce distinct integer results. However, the programmer should be aware that producing distinct integer results for unequal objects may improve the performance of hashtables.

As much as is reasonably practical, the hashCode method defined by class Object does return distinct integers for distinct objects. (This is typically implemented by converting the internal address of the object into an integer, but this implementation technique is not required by the Java^TM programming language.)

Overrides:

hashCode in class Object

Returns:

a hash code value for this object.

See Also:

Object.equals(java.lang.Object), Hashtable