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A framework for constructing recognizers, compilers, and translators from grammatical descriptions containing Java, C#, C++, or Python actions.
/*
[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.Token;
import org.antlr.runtime.TokenStream;
import org.antlr.runtime.misc.IntArray;
import java.util.*;
/** A buffered stream of tree nodes. Nodes can be from a tree of ANY kind.
*
* This node stream sucks all nodes out of the tree specified in
* the constructor during construction and makes pointers into
* the tree using an array of Object pointers. The stream necessarily
* includes pointers to DOWN and UP and EOF nodes.
*
* This stream knows how to mark/release for backtracking.
*
* This stream is most suitable for tree interpreters that need to
* jump around a lot or for tree parsers requiring speed (at cost of memory).
* There is some duplicated functionality here with UnBufferedTreeNodeStream
* but just in bookkeeping, not tree walking etc...
*
* TARGET DEVELOPERS:
*
* This is the old CommonTreeNodeStream that buffered up entire node stream.
* No need to implement really as new CommonTreeNodeStream is much better
* and covers what we need.
*
* @see CommonTreeNodeStream
*/
public class BufferedTreeNodeStream implements TreeNodeStream {
public static final int DEFAULT_INITIAL_BUFFER_SIZE = 100;
public static final int INITIAL_CALL_STACK_SIZE = 10;
protected class StreamIterator implements Iterator {
int i = 0;
public boolean hasNext() {
return i=0 &&
(adaptor.getType(get(i))==Token.EOF ||
adaptor.getType(get(i))==Token.UP ||
adaptor.getType(get(i))==Token.DOWN) )
{
i--;
}
System.out.println("stop at node: "+i+" "+nodes.get(i));
return nodes.get(i);
}
*/
/** Look backwards k nodes */
protected Object LB(int k) {
if ( k==0 ) {
return null;
}
if ( (p-k)<0 ) {
return null;
}
return nodes.get(p-k);
}
public Object getTreeSource() {
return root;
}
public String getSourceName() {
return getTokenStream().getSourceName();
}
public TokenStream getTokenStream() {
return tokens;
}
public void setTokenStream(TokenStream tokens) {
this.tokens = tokens;
}
public TreeAdaptor getTreeAdaptor() {
return adaptor;
}
public void setTreeAdaptor(TreeAdaptor adaptor) {
this.adaptor = adaptor;
}
public boolean hasUniqueNavigationNodes() {
return uniqueNavigationNodes;
}
public void setUniqueNavigationNodes(boolean uniqueNavigationNodes) {
this.uniqueNavigationNodes = uniqueNavigationNodes;
}
public void consume() {
if ( p==-1 ) {
fillBuffer();
}
p++;
}
public int LA(int i) {
return adaptor.getType(LT(i));
}
public int mark() {
if ( p==-1 ) {
fillBuffer();
}
lastMarker = index();
return lastMarker;
}
public void release(int marker) {
// no resources to release
}
public int index() {
return p;
}
public void rewind(int marker) {
seek(marker);
}
public void rewind() {
seek(lastMarker);
}
public void seek(int index) {
if ( p==-1 ) {
fillBuffer();
}
p = index;
}
/** Make stream jump to a new location, saving old location.
* Switch back with pop().
*/
public void push(int index) {
if ( calls==null ) {
calls = new IntArray();
}
calls.push(p); // save current index
seek(index);
}
/** Seek back to previous index saved during last push() call.
* Return top of stack (return index).
*/
public int pop() {
int ret = calls.pop();
seek(ret);
return ret;
}
public void reset() {
p = 0;
lastMarker = 0;
if (calls != null) {
calls.clear();
}
}
public int size() {
if ( p==-1 ) {
fillBuffer();
}
return nodes.size();
}
public Iterator iterator() {
if ( p==-1 ) {
fillBuffer();
}
return new StreamIterator();
}
// TREE REWRITE INTERFACE
public void replaceChildren(Object parent, int startChildIndex, int stopChildIndex, Object t) {
if ( parent!=null ) {
adaptor.replaceChildren(parent, startChildIndex, stopChildIndex, t);
}
}
/** Used for testing, just return the token type stream */
public String toTokenTypeString() {
if ( p==-1 ) {
fillBuffer();
}
StringBuffer buf = new StringBuffer();
for (int i = 0; i < nodes.size(); i++) {
Object t = (Object) nodes.get(i);
buf.append(" ");
buf.append(adaptor.getType(t));
}
return buf.toString();
}
/** Debugging */
public String toTokenString(int start, int stop) {
if ( p==-1 ) {
fillBuffer();
}
StringBuffer buf = new StringBuffer();
for (int i = start; i < nodes.size() && i <= stop; i++) {
Object t = (Object) nodes.get(i);
buf.append(" ");
buf.append(adaptor.getToken(t));
}
return buf.toString();
}
public String toString(Object start, Object stop) {
System.out.println("toString");
if ( start==null || stop==null ) {
return null;
}
if ( p==-1 ) {
fillBuffer();
}
//System.out.println("stop: "+stop);
if ( start instanceof CommonTree )
System.out.print("toString: "+((CommonTree)start).getToken()+", ");
else
System.out.println(start);
if ( stop instanceof CommonTree )
System.out.println(((CommonTree)stop).getToken());
else
System.out.println(stop);
// if we have the token stream, use that to dump text in order
if ( tokens!=null ) {
int beginTokenIndex = adaptor.getTokenStartIndex(start);
int endTokenIndex = adaptor.getTokenStopIndex(stop);
// if it's a tree, use start/stop index from start node
// else use token range from start/stop nodes
if ( adaptor.getType(stop)==Token.UP ) {
endTokenIndex = adaptor.getTokenStopIndex(start);
}
else if ( adaptor.getType(stop)==Token.EOF ) {
endTokenIndex = size()-2; // don't use EOF
}
return tokens.toString(beginTokenIndex, endTokenIndex);
}
// walk nodes looking for start
Object t = null;
int i = 0;
for (; i < nodes.size(); i++) {
t = nodes.get(i);
if ( t==start ) {
break;
}
}
// now walk until we see stop, filling string buffer with text
StringBuffer buf = new StringBuffer();
t = nodes.get(i);
while ( t!=stop ) {
String text = adaptor.getText(t);
if ( text==null ) {
text = " "+String.valueOf(adaptor.getType(t));
}
buf.append(text);
i++;
t = nodes.get(i);
}
// include stop node too
String text = adaptor.getText(stop);
if ( text==null ) {
text = " "+String.valueOf(adaptor.getType(stop));
}
buf.append(text);
return buf.toString();
}
}