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1   /**
2    * Redistribution  and use  in source  and binary  forms, with  or without
3    * modification, are permitted provided  that the following conditions are
4    * met :
5    *
6    * . Redistributions  of  source  code  must  retain  the  above copyright
7    *   notice, this list of conditions and the following disclaimer.
8    *
9    * . Redistributions in  binary form  must reproduce  the above  copyright
10   *   notice, this list of conditions  and the following disclaimer in  the
11   *   documentation and/or other materials provided with the distribution.
12   *
13   * . The name of the author may not be used to endorse or promote products
14   *   derived from this software without specific prior written permission.
15   *
16   * THIS SOFTWARE IS  PROVIDED BY THE  AUTHOR ``AS IS''  AND ANY EXPRESS  OR
17   * IMPLIED  WARRANTIES,  INCLUDING,  BUT   NOT  LIMITED  TO,  THE   IMPLIED
18   * WARRANTIES OF MERCHANTABILITY AND  FITNESS FOR A PARTICULAR  PURPOSE ARE
19   * DISCLAIMED.  IN NO  EVENT SHALL  THE AUTHOR  BE LIABLE  FOR ANY  DIRECT,
20   * INDIRECT,  INCIDENTAL,  SPECIAL,  EXEMPLARY,  OR  CONSEQUENTIAL  DAMAGES
21   * (INCLUDING,  BUT  NOT LIMITED  TO,  PROCUREMENT OF  SUBSTITUTE  GOODS OR
22   * SERVICES;  LOSS  OF USE,  DATA,  OR PROFITS;  OR  BUSINESS INTERRUPTION)
23   * HOWEVER CAUSED  AND ON  ANY THEORY  OF LIABILITY,  WHETHER IN  CONTRACT,
24   * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
25   * ANY  WAY  OUT OF  THE  USE OF  THIS  SOFTWARE, EVEN  IF  ADVISED OF  THE
26   * POSSIBILITY OF SUCH DAMAGE.
27   */
28  
29  package cppast;
30  
31  /**
32   * Manages the symbol table and scopes.
33   *
34   * @author Mathieu Champlon
35   */
36  public final class SymbolTable
37  {
38      private final Scope root;
39      private Scope current;
40  
41      /**
42       * Creates a symbol table.
43       */
44      public SymbolTable()
45      {
46          root = new Scope();
47          current = root;
48      }
49  
50      /**
51       * Opens a scope of a given name.
52       *
53       * @param name a non-null scope name
54       */
55      public void openScope( final String name )
56      {
57          final Scope scope = current.getScope( name );
58          if( scope != null )
59              current = scope;
60          else
61              current = current.createScope( name );
62      }
63  
64      /**
65       * Close current scope.
66       */
67      public void closeScope()
68      {
69          current = current.close();
70      }
71  
72      /**
73       * Close all scopes.
74       */
75      public void closeScopes()
76      {
77          current = root;
78      }
79  
80      public Scope getCurrentScope()
81      {
82          return current;
83      }
84  
85      /**
86       * Extend the current scope with another scope.
87       *
88       * @param name the name of the extension scope
89       */
90      public void extend( final String name )
91      {
92          current.extend( getScope( name ) );
93      }
94  
95      private Scope getScope( final String name )
96      {
97          if( name == null )
98              return null;
99          if( name.indexOf( "::" ) == 0 )
100             return root.getScope( name.substring( 2 ) );
101         return current.getScope( name );
102     }
103 }