org.codehaus.groovy.antlr.AntlrASTProcessSnippets Maven / Gradle / Ivy
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* Licensed to the Apache Software Foundation (ASF) under one
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* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
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* KIND, either express or implied. See the License for the
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*/
package org.codehaus.groovy.antlr;
/**
* Process to decorate antlr AST with ending line/col info, and if
* possible the snippet of source from the start/end line/col for each node.
*
* @author Jeremy Rayner
*/
import antlr.collections.AST;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
public class AntlrASTProcessSnippets implements AntlrASTProcessor{
public AntlrASTProcessSnippets() {
}
/**
* decorate antlr AST with ending line/col info, and if
* possible the snippet of source from the start/end line/col for each node.
* @param t the AST to decorate
* @return the decorated AST
*/
public AST process(AST t) {
// first visit
List l = new ArrayList();
traverse((GroovySourceAST)t,l,null);
//System.out.println("l:" + l);
// second visit
Iterator itr = l.iterator();
if (itr.hasNext()) { itr.next(); /* discard first */ }
traverse((GroovySourceAST)t,null,itr);
return t;
}
/**
* traverse an AST node
* @param t the AST node to traverse
* @param l A list to add line/col info to
* @param itr An iterator over a list of line/col
*/
private void traverse(GroovySourceAST t,List l,Iterator itr) {
while (t != null) {
// first visit of node
if (l != null) {
l.add(new LineColumn(t.getLine(),t.getColumn()));
}
// second visit of node
if (itr != null && itr.hasNext()) {
LineColumn lc = (LineColumn)itr.next();
if (t.getLineLast() == 0) {
int nextLine = lc.getLine();
int nextColumn = lc.getColumn();
if (nextLine < t.getLine() || (nextLine == t.getLine() && nextColumn < t.getColumn())) {
nextLine = t.getLine();
nextColumn = t.getColumn();
}
t.setLineLast(nextLine);
t.setColumnLast(nextColumn);
// This is a good point to call t.setSnippet(),
// but it bulks up the AST too much for production code.
}
}
GroovySourceAST child = (GroovySourceAST)t.getFirstChild();
if (child != null) {
traverse(child,l,itr);
}
t = (GroovySourceAST)t.getNextSibling();
}
}
}