1 files changed, 142 insertions, 0 deletions
diff --git a/libjava/classpath/gnu/javax/swing/text/html/parser/support/low/Queue.java b/libjava/classpath/gnu/javax/swing/text/html/parser/support/low/Queue.java
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+/* Queue.java -- a token queue.
+   Copyright (C) 2005 Free Software Foundation, Inc.
+
+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., 51 Franklin Street, Fifth Floor, Boston, MA
+02110-1301 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 gnu.javax.swing.text.html.parser.support.low;
+
+import java.util.Arrays;
+
+/**
+ * A token queue.
+ * @author Audrius Meskauskas, Lithuania (AudriusA@Bioinformatics.org)
+ */
+public class Queue
+{
+  Token[] m = new Token[ 64 ];
+  int a = 0;
+  int b = 0;
+
+  /**
+   * True for the empty queue.
+   */
+  public boolean isEmpty()
+  {
+    return size() == 0;
+  }
+
+  /**
+   *  Add this trace to the end of the queue.
+   */
+  public void add(Token u)
+  {
+    if (a < m.length)
+      {
+        m [ a ] = u;
+        a++;
+      }
+    else // The end of array has been reached.
+      {
+        if (b > 0) // If some elements were deleted from the start of the queue, shift.
+          {
+            int d = b;
+            System.arraycopy(m, b, m, 0, a - b);
+            b = b - d;
+            a = a - d;
+            m [ a ] = u;
+            a++;
+          }
+        else // Enlarge the queue, doubling the size.
+          {
+            int n = m.length * 2;
+            Token[] nm = new Token[ 2 * n ];
+            System.arraycopy(m, 0, nm, 0, m.length);
+            Arrays.fill(m, null);
+
+            nm [ a ] = u;
+            m = nm;
+            a++;
+          }
+      }
+  }
+
+  /**
+   * Clear the queue.
+   */
+  public void clear()
+  {
+    a = b = 0;
+    Arrays.fill(m, null);
+  }
+
+  /**
+   * Read the value ahead. 0 is the value that will be returned with
+   * the following next. This method does not remove values from the
+   * queue. To test if there is enough tokens in the queue, size() must
+   * be checked before calling this method.
+   */
+  public Token get(int ahead)
+  {
+    int p = b + ahead;
+    if (p < a)
+      return m [ p ];
+    else
+      throw new ArrayIndexOutOfBoundsException("Not enough tokens");
+  }
+
+  /**
+   * Read the oldest value from the queue and remove this value from
+   * the queue.
+   */
+  public Token next()
+  {
+    if (a == b)
+      throw new ArrayIndexOutOfBoundsException("queue empty");
+
+    Token r = m [ b ];
+    m [ b ] = null;
+    b++;
+    return r;
+  }
+
+  /**
+   * Size of the queue.
+   */
+  public int size()
+  {
+    return a - b;
+  }
+}