/*
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 Copyright (c) 2005-2009 Terence Parr
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package org.antlr.runtime.debug;

import org.antlr.runtime.Token;
import org.antlr.runtime.TokenStream;
import org.antlr.runtime.RecognitionException;
import org.antlr.runtime.tree.TreeAdaptor;

A TreeAdaptor proxy that fires debugging events to a DebugEventListener delegate and uses the TreeAdaptor delegate to do the actual work. All AST events are triggered by this adaptor; no code gen changes are needed in generated rules. Debugging events are triggered *after* invoking tree adaptor routines. Trees created with actions in rewrite actions like "-> ^(ADD {foo} {bar})" cannot be tracked as they might not use the adaptor to create foo, bar. The debug listener has to deal with tree node IDs for which it did not see a createNode event. A single <unknown> node is sufficient even if it represents a whole tree.
/** A TreeAdaptor proxy that fires debugging events to a DebugEventListener * delegate and uses the TreeAdaptor delegate to do the actual work. All * AST events are triggered by this adaptor; no code gen changes are needed * in generated rules. Debugging events are triggered *after* invoking * tree adaptor routines. * * Trees created with actions in rewrite actions like "-&gt; ^(ADD {foo} {bar})" * cannot be tracked as they might not use the adaptor to create foo, bar. * The debug listener has to deal with tree node IDs for which it did * not see a createNode event. A single &lt;unknown&gt; node is sufficient even * if it represents a whole tree. */
public class DebugTreeAdaptor implements TreeAdaptor { protected DebugEventListener dbg; protected TreeAdaptor adaptor; public DebugTreeAdaptor(DebugEventListener dbg, TreeAdaptor adaptor) { this.dbg = dbg; this.adaptor = adaptor; } @Override public Object create(Token payload) { if ( payload.getTokenIndex() < 0 ) { // could be token conjured up during error recovery return create(payload.getType(), payload.getText()); } Object node = adaptor.create(payload); dbg.createNode(node, payload); return node; } @Override public Object errorNode(TokenStream input, Token start, Token stop, RecognitionException e) { Object node = adaptor.errorNode(input, start, stop, e); if ( node!=null ) { dbg.errorNode(node); } return node; } @Override public Object dupTree(Object tree) { Object t = adaptor.dupTree(tree); // walk the tree and emit create and add child events // to simulate what dupTree has done. dupTree does not call this debug // adapter so I must simulate. simulateTreeConstruction(t); return t; }
^(A B C): emit create A, create B, add child, ...
/** ^(A B C): emit create A, create B, add child, ...*/
protected void simulateTreeConstruction(Object t) { dbg.createNode(t); int n = adaptor.getChildCount(t); for (int i=0; i<n; i++) { Object child = adaptor.getChild(t, i); simulateTreeConstruction(child); dbg.addChild(t, child); } } @Override public Object dupNode(Object treeNode) { Object d = adaptor.dupNode(treeNode); dbg.createNode(d); return d; } @Override public Object nil() { Object node = adaptor.nil(); dbg.nilNode(node); return node; } @Override public boolean isNil(Object tree) { return adaptor.isNil(tree); } @Override public void addChild(Object t, Object child) { if ( t==null || child==null ) { return; } adaptor.addChild(t,child); dbg.addChild(t, child); } @Override public Object becomeRoot(Object newRoot, Object oldRoot) { Object n = adaptor.becomeRoot(newRoot, oldRoot); dbg.becomeRoot(newRoot, oldRoot); return n; } @Override public Object rulePostProcessing(Object root) { return adaptor.rulePostProcessing(root); } public void addChild(Object t, Token child) { Object n = this.create(child); this.addChild(t, n); } @Override public Object becomeRoot(Token newRoot, Object oldRoot) { Object n = this.create(newRoot); adaptor.becomeRoot(n, oldRoot); dbg.becomeRoot(newRoot, oldRoot); return n; } @Override public Object create(int tokenType, Token fromToken) { Object node = adaptor.create(tokenType, fromToken); dbg.createNode(node); return node; } @Override public Object create(int tokenType, Token fromToken, String text) { Object node = adaptor.create(tokenType, fromToken, text); dbg.createNode(node); return node; } @Override public Object create(int tokenType, String text) { Object node = adaptor.create(tokenType, text); dbg.createNode(node); return node; } @Override public int getType(Object t) { return adaptor.getType(t); } @Override public void setType(Object t, int type) { adaptor.setType(t, type); } @Override public String getText(Object t) { return adaptor.getText(t); } @Override public void setText(Object t, String text) { adaptor.setText(t, text); } @Override public Token getToken(Object t) { return adaptor.getToken(t); } @Override public void setTokenBoundaries(Object t, Token startToken, Token stopToken) { adaptor.setTokenBoundaries(t, startToken, stopToken); if ( t!=null && startToken!=null && stopToken!=null ) { dbg.setTokenBoundaries( t, startToken.getTokenIndex(), stopToken.getTokenIndex()); } } @Override public int getTokenStartIndex(Object t) { return adaptor.getTokenStartIndex(t); } @Override public int getTokenStopIndex(Object t) { return adaptor.getTokenStopIndex(t); } @Override public Object getChild(Object t, int i) { return adaptor.getChild(t, i); } @Override public void setChild(Object t, int i, Object child) { adaptor.setChild(t, i, child); } @Override public Object deleteChild(Object t, int i) { return deleteChild(t, i); } @Override public int getChildCount(Object t) { return adaptor.getChildCount(t); } @Override public int getUniqueID(Object node) { return adaptor.getUniqueID(node); } @Override public Object getParent(Object t) { return adaptor.getParent(t); } @Override public int getChildIndex(Object t) { return adaptor.getChildIndex(t); } @Override public void setParent(Object t, Object parent) { adaptor.setParent(t, parent); } @Override public void setChildIndex(Object t, int index) { adaptor.setChildIndex(t, index); } @Override public void replaceChildren(Object parent, int startChildIndex, int stopChildIndex, Object t) { adaptor.replaceChildren(parent, startChildIndex, stopChildIndex, t); } // support public DebugEventListener getDebugListener() { return dbg; } public void setDebugListener(DebugEventListener dbg) { this.dbg = dbg; } public TreeAdaptor getTreeAdaptor() { return adaptor; } }