AWT/Swing merge from GNU Classpath.

From-SVN: r56147

libjava/javax/accessibility/AccessibleRelationSet.java

@@ -0,0 +1,222 @@
+/* AccessibleRelationSet.java -- the combined relations of an accessible object
+   Copyright (C) 2002 Free Software Foundation
+
+This file is part of GNU Classpath.
+
+GNU Classpath is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2, or (at your option)
+any later version.
+
+GNU Classpath is distributed in the hope that it will be useful, but
+WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with GNU Classpath; see the file COPYING.  If not, write to the
+Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+02111-1307 USA.
+
+Linking this library statically or dynamically with other modules is
+making a combined work based on this library.  Thus, the terms and
+conditions of the GNU General Public License cover the whole
+combination.
+
+As a special exception, the copyright holders of this library give you
+permission to link this library with independent modules to produce an
+executable, regardless of the license terms of these independent
+modules, and to copy and distribute the resulting executable under
+terms of your choice, provided that you also meet, for each linked
+independent module, the terms and conditions of the license of that
+module.  An independent module is a module which is not derived from
+or based on this library.  If you modify this library, you may extend
+this exception to your version of the library, but you are not
+obligated to do so.  If you do not wish to do so, delete this
+exception statement from your version. */
+
+package javax.accessibility;
+
+import java.util.Vector;
+
+/**
+ * Describes all relations of an accessible object. For example, an object
+ * by labeled by one object and control another.
+ *
+ * @author Eric Blake <ebb9@email.byu.edu>
+ * @see AccessibleRelation
+ * @since 1.2
+ * @status updated to 1.4
+ */
+public class AccessibleRelationSet
+{
+  /**
+   * The list of relations, should be instances of AccessibleRelation. Don't
+   * set this to null.
+   *
+   * @see #add(AccessibleRelation)
+   * @see #addAll(AccessibleRelation[])
+   * @see #remove(AccessibleRelation)
+   * @see #contains(String)
+   * @see #get(String)
+   * @see #size()
+   * @see #toArray()
+   * @see #clear()
+   */
+  protected Vector relations = new Vector();
+
+  /**
+   * Create an empty relation set.
+   */
+  public AccessibleRelationSet()
+  {
+  }
+
+  /**
+   * Create a relation set initialized with the given relations, duplicates are
+   * ignored.
+   *
+   * @param relations the relations to insert
+   * @throws NullPointerException if relations is null
+   */
+  public AccessibleRelationSet(AccessibleRelation[] relations)
+  {
+    addAll(relations);
+  }
+
+  /**
+   * Add a new relation to the current set. If the relation is already in
+   * the set, the targets are merged with the existing relation, possibly
+   * resulting in an object being in the target list more than once. Do not
+   * add a relation with a null key, as it will cause problems later.
+   *
+   * @param relation the relation to add
+   * @return true if the set was modified, which is always the case
+   * @throws NullPointerException if relation is null
+   */
+  public boolean add(AccessibleRelation relation)
+  {
+    AccessibleRelation old = get(relation.key);
+    if (old == null)
+      return relations.add(relation);
+    if (old.targets.length == 0)
+      old.targets = relation.targets;
+    else if (relation.targets.length != 0)
+      {
+        Object[] t = new Object[old.targets.length + relation.targets.length];
+        System.arraycopy(old.targets, 0, t, 0, old.targets.length);
+        System.arraycopy(relation.targets, 0, t, old.targets.length,
+                         relation.targets.length);
+        old.targets = t;
+      }
+    return true;
+  }
+
+  /**
+   * Add all of the relations to the current set. Duplicates are ignored.
+   *
+   * @param array the array of relations to add
+   * @throws NullPointerException if array is null or has null entries
+   */
+  public void addAll(AccessibleRelation[] array)
+  {
+    int i = array.length;
+    while (--i >= 0)
+      add(array[i]);
+  }
+
+  /**
+   * Remove a relation from the set. If a relation was removed, return true.
+   * Note that this uses AccessibleRelation.equals, which defaults to ==, so a
+   * relation with the same key may still exist in the set afterwords.
+   *
+   * @param relation the state to remove
+   * @return true if the set changed
+   */
+  public boolean remove(AccessibleRelation relation)
+  {
+    return relations.remove(relation);
+  }
+
+  /**
+   * Clear all relations in the set.
+   */
+  public void clear()
+  {
+    relations.clear();
+  }
+
+  /**
+   * Return the number of relations in the set.
+   *
+   * @return the set size
+   */
+  public int size()
+  {
+    return relations.size();
+  }
+
+  /**
+   * Check if the relation key is in the set.
+   *
+   * @param relation the relation to locate
+   * @return true if it is in the set
+   */
+  public boolean contains(String key)
+  {
+    int i = relations.size();
+    while (--i >= 0)
+      if (((AccessibleRelation) relations.get(i)).key.equals(key))
+        return true;
+    return false;
+  }
+
+  /**
+   * Get the relation that matches the key.
+   *
+   * @param relation the relation to locate
+   * @return the relation in the set, or null
+   */
+  public AccessibleRelation get(String key)
+  {
+    int i = relations.size();
+    while (--i >= 0)
+      {
+        AccessibleRelation r = (AccessibleRelation) relations.get(i);
+        if (r.key.equals(key))
+          return r;
+      }
+    return null;
+  }
+
+  /**
+   * Return the relation set as an array.
+   *
+   * @return an array of the current relations
+   */
+  public AccessibleRelation[] toArray()
+  {
+    AccessibleRelation[] result = new AccessibleRelation[relations.size()];
+    relations.toArray(result);
+    return result;
+  }
+
+  /**
+   * Return a localized, comma-separated string representing all relations
+   * in the set. This is in arbitrary order.
+   *
+   * @return the string representation
+   * @see AccessibleBundle#toDisplayString(String, Locale)
+   */
+  public String toString()
+  {
+    int i = relations.size();
+    if (i == 0)
+      return "";
+    // Pre-allocate an average of 10 chars per state.
+    StringBuffer b = new StringBuffer(i * 10);
+    while (--i >= 0)
+      b.append(relations.get(i)).append(',');
+    return b.substring(0, b.length() - 1);
+  }
+} // class AccessibleRelationSet