code: //==============================================================================
  //	
  //	Copyright (c) 2016-
  //	Authors:
  //	* Joachim Klein <klein@tcs.inf.tu-dresden.de> (TU Dresden)
  //	
  //------------------------------------------------------------------------------
  //	
  //	This file is part of PRISM.
  //	
  //	PRISM 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 of the License, or
  //	(at your option) any later version.
  //	
  //	PRISM 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 PRISM; if not, write to the Free Software Foundation,
  //	Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  //	
  //==============================================================================
  
  
  package parser.visitor;
  
  import java.util.HashMap;
  import java.util.Map;
  
  import parser.ast.ExpressionLabel;
  
  /** Visitor for replacing some labels in an expression by other labels */
  public class ReplaceLabels extends ASTTraverseModify
  {
  	/** The replacement map */
  	private Map<String, String> replacements;
  
  	/** Constructor for multiple replacements (from -> to) */
  	public ReplaceLabels(Map<String, String> replacements)
  	{
  		this.replacements = replacements;
  	}
  
  	/** Constructor for a single replacement */
  	public ReplaceLabels(String labelFrom, String labelTo)
  	{
  		replacements = new HashMap<String,String>();
  		replacements.put(labelFrom, labelTo);
  	}
  
  	@Override
  	public Object visit(ExpressionLabel e)
  	{
  		if (e.getName() == null)
  			return e;
  
  		String replacement = replacements.get(e.getName());
  		if (replacement != null)
  			return new ExpressionLabel(replacement);
  
  		return e;
  	}
  
  }
  