| /* |
| [The "BSD license"] |
| Copyright (c) 2005-2009 Terence Parr |
| All rights reserved. |
| |
| Redistribution and use in source and binary forms, with or without |
| modification, are permitted provided that the following conditions |
| are met: |
| 1. Redistributions of source code must retain the above copyright |
| notice, this list of conditions and the following disclaimer. |
| 2. Redistributions in binary form must reproduce the above copyright |
| notice, this list of conditions and the following disclaimer in the |
| documentation and/or other materials provided with the distribution. |
| 3. The name of the author may not be used to endorse or promote products |
| derived from this software without specific prior written permission. |
| |
| THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR |
| IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
| OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. |
| IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, |
| INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
| NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF |
| THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| */ |
| package org.antlr.runtime.tree; |
| |
| import org.antlr.runtime.CommonToken; |
| import org.antlr.runtime.Token; |
| |
| /** A TreeAdaptor that works with any Tree implementation. It provides |
| * really just factory methods; all the work is done by BaseTreeAdaptor. |
| * If you would like to have different tokens created than ClassicToken |
| * objects, you need to override this and then set the parser tree adaptor to |
| * use your subclass. |
| * |
| * To get your parser to build nodes of a different type, override |
| * create(Token), errorNode(), and to be safe, YourTreeClass.dupNode(). |
| * dupNode is called to duplicate nodes during rewrite operations. |
| */ |
| public class CommonTreeAdaptor extends BaseTreeAdaptor { |
| /** Duplicate a node. This is part of the factory; |
| * override if you want another kind of node to be built. |
| * |
| * I could use reflection to prevent having to override this |
| * but reflection is slow. |
| */ |
| public Object dupNode(Object t) { |
| if ( t==null ) return null; |
| return ((Tree)t).dupNode(); |
| } |
| |
| public Object create(Token payload) { |
| return new CommonTree(payload); |
| } |
| |
| /** Tell me how to create a token for use with imaginary token nodes. |
| * For example, there is probably no input symbol associated with imaginary |
| * token DECL, but you need to create it as a payload or whatever for |
| * the DECL node as in ^(DECL type ID). |
| * |
| * If you care what the token payload objects' type is, you should |
| * override this method and any other createToken variant. |
| */ |
| public Token createToken(int tokenType, String text) { |
| return new CommonToken(tokenType, text); |
| } |
| |
| /** Tell me how to create a token for use with imaginary token nodes. |
| * For example, there is probably no input symbol associated with imaginary |
| * token DECL, but you need to create it as a payload or whatever for |
| * the DECL node as in ^(DECL type ID). |
| * |
| * This is a variant of createToken where the new token is derived from |
| * an actual real input token. Typically this is for converting '{' |
| * tokens to BLOCK etc... You'll see |
| * |
| * r : lc='{' ID+ '}' -> ^(BLOCK[$lc] ID+) ; |
| * |
| * If you care what the token payload objects' type is, you should |
| * override this method and any other createToken variant. |
| */ |
| public Token createToken(Token fromToken) { |
| return new CommonToken(fromToken); |
| } |
| |
| /** Track start/stop token for subtree root created for a rule. |
| * Only works with Tree nodes. For rules that match nothing, |
| * seems like this will yield start=i and stop=i-1 in a nil node. |
| * Might be useful info so I'll not force to be i..i. |
| */ |
| public void setTokenBoundaries(Object t, Token startToken, Token stopToken) { |
| if ( t==null ) return; |
| int start = 0; |
| int stop = 0; |
| if ( startToken!=null ) start = startToken.getTokenIndex(); |
| if ( stopToken!=null ) stop = stopToken.getTokenIndex(); |
| ((Tree)t).setTokenStartIndex(start); |
| ((Tree)t).setTokenStopIndex(stop); |
| } |
| |
| public int getTokenStartIndex(Object t) { |
| if ( t==null ) return -1; |
| return ((Tree)t).getTokenStartIndex(); |
| } |
| |
| public int getTokenStopIndex(Object t) { |
| if ( t==null ) return -1; |
| return ((Tree)t).getTokenStopIndex(); |
| } |
| |
| public String getText(Object t) { |
| if ( t==null ) return null; |
| return ((Tree)t).getText(); |
| } |
| |
| public int getType(Object t) { |
| if ( t==null ) return Token.INVALID_TOKEN_TYPE; |
| return ((Tree)t).getType(); |
| } |
| |
| /** What is the Token associated with this node? If |
| * you are not using CommonTree, then you must |
| * override this in your own adaptor. |
| */ |
| public Token getToken(Object t) { |
| if ( t instanceof CommonTree ) { |
| return ((CommonTree)t).getToken(); |
| } |
| return null; // no idea what to do |
| } |
| |
| public Object getChild(Object t, int i) { |
| if ( t==null ) return null; |
| return ((Tree)t).getChild(i); |
| } |
| |
| public int getChildCount(Object t) { |
| if ( t==null ) return 0; |
| return ((Tree)t).getChildCount(); |
| } |
| |
| public Object getParent(Object t) { |
| if ( t==null ) return null; |
| return ((Tree)t).getParent(); |
| } |
| |
| public void setParent(Object t, Object parent) { |
| if ( t!=null ) ((Tree)t).setParent((Tree)parent); |
| } |
| |
| public int getChildIndex(Object t) { |
| if ( t==null ) return 0; |
| return ((Tree)t).getChildIndex(); |
| } |
| |
| public void setChildIndex(Object t, int index) { |
| if ( t!=null ) ((Tree)t).setChildIndex(index); |
| } |
| |
| public void replaceChildren(Object parent, int startChildIndex, int stopChildIndex, Object t) { |
| if ( parent!=null ) { |
| ((Tree)parent).replaceChildren(startChildIndex, stopChildIndex, t); |
| } |
| } |
| } |