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diff --git a/libjava/classpath/gnu/javax/swing/text/html/parser/models/node.java b/libjava/classpath/gnu/javax/swing/text/html/parser/models/node.java
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@@ -0,0 +1,339 @@
+/* node.java --
+   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.models;
+
+import gnu.java.lang.CPStringBuilder;
+
+import java.io.Serializable;
+
+/**
+ * Part of the internal representation of the content model.
+ * @author Audrius Meskauskas, Lithuania (AudriusA@Bioinformatics.org)
+ */
+public class node
+  implements Serializable
+{
+  private static final long serialVersionUID = 1;
+
+  /**
+   * The token to match (can be instance of list).
+   */
+  public Object token;
+
+  /**
+   * True for the node that cannot be visited again.
+   */
+  public boolean _closed;
+
+  /**
+   * The binary operation for this node.
+   */
+  public char binary;
+
+  /**
+   * The unary opeation for this node.
+   */
+  public char unary;
+
+  /**
+   * The number of times the node already was visited.
+   */
+  public int visits;
+
+  /**
+   * The previous node in content model (used for closing nodes).
+   */
+  public node previous;
+
+  /**
+   * Creates a new node.
+   * @param binary_operator The operator, connecting all nodes in the list.
+   * The nodes, connected by the different operators, must be arranged into
+   * the different lists.
+   * @param unary_operator The unary operator for this node or zero if
+   * no such was specified.
+   * @param token The token to match. This can be either a string or
+   * the new instance of the list.
+   * @param a_previous The previous node in the list, null for the first
+   * node. This is used for propagating the closing operation for the
+   * comma delimited list.
+   */
+  public node(char binary_operator, char unary_operator, Object a_token)
+  {
+    if (a_token != null)
+      if (a_token.getClass().equals(node.class))
+        throw new Error("Creating node in node is redundant and ineffective.");
+
+    binary = binary_operator;
+    unary = unary_operator;
+    token = a_token;
+  }
+
+  /**
+   * Checks if this node is in the closed state.
+   * @return True if the node is closed.
+   */
+  public boolean isClosed()
+  {
+    return _closed;
+  }
+
+  /**
+   * Check if closing this node means closing the previous node.
+   */
+  public boolean closePrevious()
+  {
+    return binary == ',';
+  }
+
+  /**
+   * Return the token object if it could match as a next token in
+   * a token list of null if it could not.
+   * @return
+   */
+  public Object findFreeNode()
+  {
+    boolean ok;
+    if (isClosed() || silenceAllowed())
+      return null;
+
+    // Try if the node would stay valid after a one more visit.
+    visits++;
+    ok = valid();
+    visits--;
+
+    if (ok)
+      {
+        if (token instanceof node)
+          return ((node) token).findFreeNode();
+        else
+          return token;
+      }
+    else
+      return null;
+  }
+
+  /**
+   * Check if the current situation is such that the node must be closed
+   * now.
+   */
+  public boolean mustClose()
+  {
+    switch (unary)
+      {
+        case 0 :
+          return true;
+
+        case '*' :
+          return false;
+
+        case '+' :
+          return false;
+
+        case '?' :
+          return visits <= 1;
+
+        default :
+          throw new Error("Invalid unary operation " + unary + " ( '" +
+                          (char) unary + "' )"
+                         );
+      }
+  }
+
+  /**
+   * Do the match operation with the given token. This sets various
+   * flags.
+   * @param a_token The token to match.
+   * @return true if the the token matches node, false if it does not match
+   * or if the node is closed.
+   */
+  public boolean performMatch(Object a_token)
+  {
+    if (isClosed())
+      return false;
+
+    boolean matches = compare(a_token);
+    if (matches)
+      matches();
+
+    return matches;
+  }
+
+  /**
+   * Prepares the node for matching against a new list of tokens.
+   */
+  public void reset()
+  {
+    _closed = false;
+    visits = 0;
+  }
+
+  /**
+   * Check if the provided token can match this node.
+   * In the case of match, the node state changes, moving
+   * current position after the matched token. However if this method
+   * returns a suggested new token to insert before the provided one,
+   * the state of the list does not change.
+   * @return Boolean.TRUE if the match is found,
+   * Boolean.FALSE if the match is not possible and no token can be
+   * inserted to make the match valid. Otherwise, returns the
+   * token object that can be inserted before the last token in the
+   * list, probably (not for sure) making the match valid.
+   */
+  public Object show(Object x)
+  {
+    if (compare(x))
+      return performMatch(x) ? Boolean.TRUE : Boolean.FALSE;
+
+    Object recommended = findFreeNode();
+    return recommended != null ? recommended : Boolean.FALSE;
+  }
+
+  /**
+   * Check if it would be a valid case if this node is visited zero times.
+   * Nodes with unary operator * or ? need not be matched to make a
+   * model valid.
+   */
+  public boolean silenceAllowed()
+  {
+    return unary == '?' || unary == '*';
+  }
+
+  /**
+   * Returns a string representation of the list.
+   * @return String representation, similar to BNF expression.
+   */
+  public String toString()
+  {
+    CPStringBuilder b = new CPStringBuilder();
+
+    b.append(token);
+    if (unary != 0)
+      b.append((char) unary);
+    else
+      b.append('\'');
+
+    return b.toString();
+  }
+
+  /**
+   * Check if the node state is valid.
+   */
+  public boolean valid()
+  {
+    switch (unary)
+      {
+        case 0 :
+          if (binary == '|')
+            return true;
+          else
+            return visits == 1;
+
+        case '*' :
+          return true;
+
+        case '+' :
+          return visits > 0;
+
+        case '?' :
+          return visits <= 1;
+
+        default :
+          throw new Error("Invalid unary operation " + unary + " ( '" +
+                          (char) unary + "' )"
+                         );
+      }
+  }
+
+  public boolean validPreliminary()
+  {
+    return visits == 0 || valid();
+  }
+
+  /**
+  * Closes this node and, if closePrevious() returs true, calls close() for
+  * the previous node.
+  */
+  protected void close()
+  {
+    _closed = true;
+    if (previous != null && closePrevious())
+      previous.close();
+  }
+
+  /**
+   * Compare the provided token object with the token object of this node.
+   */
+  protected boolean compare(Object a_token)
+  {
+    if (token instanceof Object[])
+      throw new Error("Invalid token object, probably the 'list' " +
+                      "should be used. "
+                     );
+
+    if (token instanceof node[])
+      throw new Error("Do not use 'node' for the array of nodes, use 'list'. ");
+
+    if (token instanceof node)
+      {
+        return ((node) token).performMatch(a_token);
+      }
+
+    boolean rt = false;
+
+    if (token == a_token)
+      rt = true;
+    if (token.equals(a_token))
+      rt = true;
+    if (token.toString().equalsIgnoreCase(a_token.toString()))
+      rt = true;
+
+    return rt;
+  }
+
+  /**
+   * Fire the changes that must happen then the token matches this node.
+   */
+  protected void matches()
+  {
+    visits++;
+    if (mustClose())
+      close();
+  }
+}