/*
* @(#)AttributeSet.java 1.10 05/11/17
*
* Copyright 2006 Sun Microsystems, Inc. All rights reserved.
* SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
*/
package javax.print.attribute;
/**
* Interface AttributeSet specifies the interface for a set of printing
* attributes. A printing attribute is an object whose class implements
* interface {@link Attribute Attribute}.
* <P>
* An attribute set contains a group of <I>attribute values,</I>
* where duplicate values are not allowed in the set.
* Furthermore, each value in an attribute set is
* a member of some <I>category,</I> and at most one value in any particular
* category is allowed in the set. For an attribute set, the values are {@link
* Attribute Attribute} objects, and the categories are {@link java.lang.Class
* Class} objects. An attribute's category is the class (or interface) at the
* root of the class hierarchy for that kind of attribute. Note that an
* attribute object's category may be a superclass of the attribute object's
* class rather than the attribute object's class itself. An attribute
* object's
* category is determined by calling the {@link Attribute#getCategory()
* <CODE>getCategory()</CODE>} method defined in interface {@link Attribute
* Attribute}.
* <P>
* The interfaces of an AttributeSet resemble those of the Java Collections
* API's java.util.Map interface, but is more restrictive in the types
* it will accept, and combines keys and values into an Attribute.
* <P>
* Attribute sets are used in several places in the Print Service API. In
* each context, only certain kinds of attributes are allowed to appear in the
* attribute set, as determined by the tagging interfaces which the attribute
* class implements -- {@link DocAttribute DocAttribute}, {@link
* PrintRequestAttribute PrintRequestAttribute}, {@link PrintJobAttribute
* PrintJobAttribute}, and {@link PrintServiceAttribute
* PrintServiceAttribute}.
* There are four specializations of an attribute set that are restricted to
* contain just one of the four kinds of attribute -- {@link DocAttributeSet
* DocAttributeSet}, {@link PrintRequestAttributeSet
* PrintRequestAttributeSet},
* {@link PrintJobAttributeSet PrintJobAttributeSet}, and {@link
* PrintServiceAttributeSet PrintServiceAttributeSet}, respectively. Note that
* many attribute classes implement more than one tagging interface and so may
* appear in more than one context.
* <UL>
* <LI>
* A {@link DocAttributeSet DocAttributeSet}, containing {@link DocAttribute
* DocAttribute}s, specifies the characteristics of an individual doc and the
* print job settings to be applied to an individual doc.
* <P>
* <LI>
* A {@link PrintRequestAttributeSet PrintRequestAttributeSet}, containing
* {@link PrintRequestAttribute PrintRequestAttribute}s, specifies the
* settings
* to be applied to a whole print job and to all the docs in the print job.
* <P>
* <LI>
* A {@link PrintJobAttributeSet PrintJobAttributeSet}, containing {@link
* PrintJobAttribute PrintJobAttribute}s, reports the status of a print job.
* <P>
* <LI>
* A {@link PrintServiceAttributeSet PrintServiceAttributeSet}, containing
* {@link PrintServiceAttribute PrintServiceAttribute}s, reports the status of
* a Print Service instance.
* </UL>
* <P>
* In some contexts, the client is only allowed to examine an attribute set's
* contents but not change them (the set is read-only). In other places, the
* client is allowed both to examine and to change an attribute set's contents
* (the set is read-write). For a read-only attribute set, calling a mutating
* operation throws an UnmodifiableSetException.
* <P>
* The Print Service API provides one implementation of interface
* AttributeSet, class {@link HashAttributeSet HashAttributeSet}.
* A client can use class {@link
* HashAttributeSet HashAttributeSet} or provide its own implementation of
* interface AttributeSet. The Print Service API also provides
* implementations of interface AttributeSet's subinterfaces -- classes {@link
* HashDocAttributeSet HashDocAttributeSet},
* {@link HashPrintRequestAttributeSet
* HashPrintRequestAttributeSet}, {@link HashPrintJobAttributeSet
* HashPrintJobAttributeSet}, and {@link HashPrintServiceAttributeSet
* HashPrintServiceAttributeSet}.
* <P>
*
* @author Alan Kaminsky
*/
public interface AttributeSet {
/**
* Returns the attribute value which this attribute set contains in the
* given attribute category. Returns <tt>null</tt> if this attribute set
* does not contain any attribute value in the given attribute category.
*
* @param category Attribute category whose associated attribute value
* is to be returned. It must be a
* {@link java.lang.Class Class}
* that implements interface {@link Attribute
* Attribute}.
*
* @return The attribute value in the given attribute category contained
* in this attribute set, or <tt>null</tt> if this attribute set
* does not contain any attribute value in the given attribute
* category.
*
* @throws NullPointerException
* (unchecked exception) Thrown if the <CODE>category</CODE> is null.
* @throws ClassCastException
* (unchecked exception) Thrown if the <CODE>category</CODE> is not a
* {@link java.lang.Class Class} that implements interface {@link
* Attribute Attribute}.
*/
public Attribute get(Class<?> category);
/**
* Adds the specified attribute to this attribute set if it is not
* already present, first removing any existing value in the same
* attribute category as the specified attribute value.
*
* @param attribute Attribute value to be added to this attribute set.
*
* @return <tt>true</tt> if this attribute set changed as a result of the
* call, i.e., the given attribute value was not already a member
* of this attribute set.
*
* @throws NullPointerException
* (unchecked exception) Thrown if the <CODE>attribute</CODE> is null.
* @throws UnmodifiableSetException
* (unchecked exception) Thrown if this attribute set does not support
* the <CODE>add()</CODE> operation.
*/
public boolean add(Attribute attribute);
/**
* Removes any attribute for this category from this attribute set if
* present. If <CODE>category</CODE> is null, then
* <CODE>remove()</CODE> does nothing and returns <tt>false</tt>.
*
* @param category Attribute category to be removed from this
* attribute set.
*
* @return <tt>true</tt> if this attribute set changed as a result of the
* call, i.e., the given attribute value had been a member of this
* attribute set.
*
* @throws UnmodifiableSetException
* (unchecked exception) Thrown if this attribute set does not support
* the <CODE>remove()</CODE> operation.
*/
public boolean remove(Class<?> category);
/**
* Removes the specified attribute from this attribute set if
* present. If <CODE>attribute</CODE> is null, then
* <CODE>remove()</CODE> does nothing and returns <tt>false</tt>.
*
* @param attribute Attribute value to be removed from this attribute set.
*
* @return <tt>true</tt> if this attribute set changed as a result of the
* call, i.e., the given attribute value had been a member of this
* attribute set.
*
* @throws UnmodifiableSetException
* (unchecked exception) Thrown if this attribute set does not support
* the <CODE>remove()</CODE> operation.
*/
public boolean remove(Attribute attribute);
/**
* Returns <tt>true</tt> if this attribute set contains an
* attribute for the specified category.
*
* @param category whose presence in this attribute set is
* to be tested.
*
* @return <tt>true</tt> if this attribute set contains an attribute
* value for the specified category.
*/
public boolean containsKey(Class<?> category);
/**
* Returns <tt>true</tt> if this attribute set contains the given
* attribute value.
*
* @param attribute Attribute value whose presence in this
* attribute set is to be tested.
*
* @return <tt>true</tt> if this attribute set contains the given
* attribute value.
*/
public boolean containsValue(Attribute attribute);
/**
* Adds all of the elements in the specified set to this attribute.
* The outcome is the same as if the =
* {@link #add(Attribute) <CODE>add(Attribute)</CODE>}
* operation had been applied to this attribute set successively with each
* element from the specified set.
* The behavior of the <CODE>addAll(AttributeSet)</CODE>
* operation is unspecified if the specified set is modified while
* the operation is in progress.
* <P>
* If the <CODE>addAll(AttributeSet)</CODE> operation throws an exception,
* the effect on this attribute set's state is implementation dependent;
* elements from the specified set before the point of the exception may
* or may not have been added to this attribute set.
*
* @param attributes whose elements are to be added to this attribute
* set.
*
* @return <tt>true</tt> if this attribute set changed as a result of the
* call.
*
* @throws UnmodifiableSetException
* (Unchecked exception) Thrown if this attribute set does not support
* the <tt>addAll(AttributeSet)</tt> method.
* @throws NullPointerException
* (Unchecked exception) Thrown if some element in the specified
* set is null.
*
* @see #add(Attribute)
*/
public boolean addAll(AttributeSet attributes);
/**
* Returns the number of attributes in this attribute set. If this
* attribute set contains more than <tt>Integer.MAX_VALUE</tt> elements,
* returns <tt>Integer.MAX_VALUE</tt>.
*
* @return The number of attributes in this attribute set.
*/
public int size();
/**
* Returns an array of the attributes contained in this set.
* @return the Attributes contained in this set as an array, zero length
* if the AttributeSet is empty.
*/
public Attribute[] toArray();
/**
* Removes all attributes from this attribute set.
*
* @throws UnmodifiableSetException
* (unchecked exception) Thrown if this attribute set does not support
* the <CODE>clear()</CODE> operation.
*/
public void clear();
/**
* Returns true if this attribute set contains no attributes.
*
* @return true if this attribute set contains no attributes.
*/
public boolean isEmpty();
/**
* Compares the specified object with this attribute set for equality.
* Returns <tt>true</tt> if the given object is also an attribute set and
* the two attribute sets contain the same attribute category-attribute
* value mappings. This ensures that the
* <tt>equals()</tt> method works properly across different
* implementations of the AttributeSet interface.
*
* @param object to be compared for equality with this attribute set.
*
* @return <tt>true</tt> if the specified object is equal to this
* attribute set.
*/
public boolean equals(Object object);
/**
* Returns the hash code value for this attribute set. The hash code of an
* attribute set is defined to be the sum of the hash codes of each entry
* in the AttributeSet.
* This ensures that <tt>t1.equals(t2)</tt> implies that
* <tt>t1.hashCode()==t2.hashCode()</tt> for any two attribute sets
* <tt>t1</tt> and <tt>t2</tt>, as required by the general contract of
* {@link java.lang.Object#hashCode() <CODE>Object.hashCode()</CODE>}.
*
* @return The hash code value for this attribute set.
*/
public int hashCode();
}