Java example source code file (PragmaHandler.java)

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Java - Java tags/keywords

ioexception, pragmahandler, preprocessor, string, symtabentry

The PragmaHandler.java Java example source code

/*
 * Copyright (c) 1999, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code 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
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */
/*
 * COMPONENT_NAME: idl.parser
 *
 * ORIGINS: 27
 *
 * Licensed Materials - Property of IBM
 * 5639-D57 (C) COPYRIGHT International Business Machines Corp. 1997, 1999
 * RMI-IIOP v1.0
 *
 */

package com.sun.tools.corba.se.idl;

// NOTES:
// - Add openScope and closeScope.

import java.io.IOException;

public abstract class PragmaHandler
{
  public abstract boolean process (String pragma, String currentToken) throws IOException;

  void init (Preprocessor p)
  {
    preprocessor = p;
  } // init

  // Utility methods.

  /** Get the current token. */
  protected String currentToken ()
  {
    return preprocessor.currentToken ();
  } // currentToken

  /** This method, given an entry name, returns the entry with that name.
      It can take fully or partially qualified names and returns the
      appropriate entry defined within the current scope.  If no entry
      exists, null is returned. */
  protected SymtabEntry getEntryForName (String string)
  {
    return preprocessor.getEntryForName (string);
  } // getEntryForName

  /** This method returns a string of all of the characters from the input
      file from the current position up to, but not including, the end-of-line
      character(s). */
  protected String getStringToEOL () throws IOException
  {
    return preprocessor.getStringToEOL ();
  } // getStringToEOL

  /** This method returns a string of all of the characters from the input
      file from the current position up to, but not including, the given
      character.  It encapsulates parenthesis and quoted strings, meaning
      it does not stop if the given character is found within parentheses
      or quotes.  For instance, given the input of `start(inside)end',
      getUntil ('n') will return "start(inside)e" */
  protected String getUntil (char c) throws IOException
  {
    return preprocessor.getUntil (c);
  } // getUntil

  /** This method returns the next token String from the input file. */
  protected String nextToken () throws IOException
  {
    return preprocessor.nextToken ();
  } // nextToken

  /** This method assumes that the current token marks the beginning
      of a scoped name.  It then parses the subsequent identifier and
      double colon tokens, builds the scoped name, and finds the symbol
      table entry with that name. */
  protected SymtabEntry scopedName () throws IOException
  {
    return preprocessor.scopedName ();
  } // scopedName

  /** Skip to the end of the line. */
  protected void skipToEOL () throws IOException
  {
    preprocessor.skipToEOL ();
  } // skipToEOL

  /** This method skips the data in the input file until the specified
      character is encountered, then it returns the next token. */
  protected String skipUntil (char c) throws IOException
  {
    return preprocessor.skipUntil (c);
  } // skipUntil

  /** This method displays a Parser Exception complete with line number
      and position information with the given message string. */
  protected void parseException (String message)
  {
    preprocessor.parseException (message);
  } // parseException

  /** This method is called when the parser encounters a left curly brace.
      An extender of PragmaHandler may find scope information useful.
      For example, the prefix pragma takes effect as soon as it is
      encountered and stays in effect until the current scope is closed.
      If a similar pragma extension is desired, then the openScope and
      closeScope methods are available for overriding.
      @param entry the symbol table entry whose scope has just been opened.
       Be aware that, since the scope has just been entered, this entry is
       incomplete at this point.  */
  protected void openScope (SymtabEntry entry)
  {
  } // openScope

  /** This method is called when the parser encounters a right curly brace.
      An extender of PragmaHandler may find scope information useful.
      For example, the prefix pragma takes effect as soon as it is
      encountered and stays in effect until the current scope is closed.
      If a similar pragma extension is desired, then the openScope and
      closeScope methods are available for overriding.
      @param entry the symbol table entry whose scope has just been closed. */
  protected void closeScope (SymtabEntry entry)
  {
  } // closeScope

  private Preprocessor preprocessor = null;
} // class PragmaHandler