/* MutableAttributeSet.java --
   Copyright (C) 2002, 2004, 2006 Free Software Foundation, Inc.

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permission to link this library with independent modules to produce an
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package javax.swing.text;

import java.util.Enumeration;

/**
 * An {@link AttributeSet} that supports modification of the stored 
 * attributes.
 * 
 * @author	Andrew Selkirk
 * @since 1.2
 */
public interface MutableAttributeSet extends AttributeSet
{
  /**
   * Adds an attribute with the given <code>name</code> and <code>value</code>
   * to the set.  If the set already contains an attribute with the given
   * <code>name</code>, the attribute value is updated.
   * 
   * @param name  the attribute name (<code>null</code> not permitted).
   * @param value  the value (<code>null</code> not permitted).
   * 
   * @throws NullPointerException if either argument is <code>null</code>.
   */
  void addAttribute(Object name, Object value);

  /**
   * Adds all the attributes from <code>attributes</code> to this set.
   * 
   * @param attributes  the set of attributes to add (<code>null</code> not
   *                    permitted).
   *                    
   * @throws NullPointerException if <code>attributes</code> is 
   *         <code>null</code>.
   */
  void addAttributes(AttributeSet attributes);

  /**
   * Removes the attribute with the specified <code>name</code>, if this 
   * attribute is defined.  This method will only remove an attribute from
   * this set, not from the resolving parent.
   * 
   * @param name  the attribute name (<code>null</code> not permitted).
   * 
   * @throws NullPointerException if <code>name</code> is <code>null</code>.
   */
  void removeAttribute(Object name);

  /**
   * Removes the attributes listed in <code>names</code>.
   * 
   * @param names  the attribute names (<code>null</code> not permitted).
   * 
   * @throws NullPointerException if <code>names</code> is <code>null</code> 
   *         or contains any <code>null</code> values.
   */
  void removeAttributes(Enumeration<?> names);

  /**
   * Removes attributes from this set if they are found in the 
   * given set.  Only attributes whose key AND value are removed.
   * Removes attributes only from this set, not from the resolving parent.  
   * Since the resolving parent is stored as an attribute, if 
   * <code>attributes</code> has the same resolving parent as this set, the
   * parent will be removed from this set.
   * 
   * @param attributes  the attributes (<code>null</code> not permitted).
   */
  void removeAttributes(AttributeSet attributes);

  /**
   * Sets the reolving parent for this set.  When looking up an attribute, if
   * it is not found in this set, then the resolving parent is also used for
   * the lookup. 
   * 
   * @param parent  the parent attribute set (<code>null</code> not permitted).
   * 
   * @throws NullPointerException if <code>parent</code> is <code>null</code>.
   */
  void setResolveParent(AttributeSet parent);
}
