package org.drools.lang.dsl;
import java.io.IOException;
import java.io.LineNumberReader;
import java.io.Reader;
import java.io.StringReader;
import java.util.ArrayList;
import java.util.HashSet;
import java.util.LinkedList;
import java.util.List;
import java.util.Set;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import org.antlr.runtime.ANTLRReaderStream;
import org.antlr.runtime.CharStream;
import org.antlr.runtime.CommonTokenStream;
import org.antlr.runtime.RecognitionException;
import org.antlr.runtime.tree.CommonTree;
import org.antlr.runtime.tree.CommonTreeNodeStream;
import org.drools.compiler.DroolsParserException;
import org.drools.compiler.ParserError;
public class DSLTokenizedMappingFile extends DSLMappingFile {
public DSLTokenizedMappingFile() {
super();
}
private static String nl = System.getProperty( "line.separator" );
private static Pattern commentPat = Pattern.compile( "^\\s*((#/?|//).*)?$" );
private static Pattern entryPat = Pattern.compile( "^\\s*\\[.+$" );
// Original line lengths, for fixing error messages.
private List<Integer> lineLengths;
// Option keywords, i.e., anything on a #/ line.
private Set<String> optionSet = new HashSet<String>();
/**
* Read a DSL file and convert it to a String. Comment lines are removed.
* Split lines are joined, inserting a space for an EOL, but maintaining the
* original number of lines by inserting EOLs. Options are recognized.
* Keeps track of original line lengths for fixing parser error messages.
* @param reader for the DSL file data
* @return the transformed DSL file
* @throws IOException
*/
private String readFile( Reader reader ) throws IOException {
lineLengths = new ArrayList<Integer>();
lineLengths.add( null );
LineNumberReader lnr = new LineNumberReader( reader );
StringBuilder sb = new StringBuilder();
int nlCount = 0;
boolean inEntry = false;
String line;
while( (line = lnr.readLine()) != null ){
lineLengths.add( line.length() );
Matcher commentMat = commentPat.matcher( line );
if( commentMat.matches() ){
if( inEntry ){
nlCount++;
} else {
sb.append( '\n' );
}
if( "#/".equals( commentMat.group( 2 ) ) ){
String[] options = commentMat.group( 1 ).substring( 2 ).trim().split( "\\s+" );
for( String option: options ){
optionSet.add( option );
}
}
continue;
}
if( entryPat.matcher( line ).matches() ){
if( inEntry ){
for( int i = 0; i < nlCount; i++ ) sb.append( '\n' );
}
sb.append( line );
nlCount = 1;
inEntry = true;
continue;
}
sb.append( ' ').append( line );
nlCount++;
}
if( inEntry ) sb.append( '\n' );
lnr.close();
// logger.info( "====== DSL definition:" );
// logger.info( sb.toString() );
return sb.toString();
}
@Override
public boolean parseAndLoad(Reader dsl) throws IOException {
List<ParserError> errors = new ArrayList<ParserError>();
String text = readFile( dsl );
dsl = new StringReader( text );
try {
DSLMapping mapping = buildFileMapping(errors, dsl);
mapping.setOptions( optionSet );
setMapping( mapping );
List<ParserError> moderr = new ArrayList<ParserError>();
for( ParserError err: errors ){
int row = err.getRow();
int col = err.getCol();
if( row > 0 ){
int len;
while( (len = lineLengths.get( row )) < col ){
col -= len + 1;
row++;
}
}
moderr.add( new ParserError( err.getMessage(), row, col ) );
}
errors = moderr;
} catch(Exception e){
final String msg = "Error parsing DSL mapping: " + e.getMessage();
ParserError parserError = new ParserError( msg, -1, 0 );
errors.add( parserError );
}
setErrors( errors );
// for( ParserError err: errors ){
// logger.error( "[" + err.getRow() + "," + err.getCol() + "]: " + err.getMessage() );
// }
return errors.isEmpty();
}
private DSLMapping buildFileMapping(final List<ParserError> errors, final Reader dsl) throws IOException, RecognitionException{
ANTLRReaderStream reader = new ANTLRReaderStream(dsl);
DSLMapWalker walker = buildFileMappingWalker(errors, reader);
DSLMapping mapping = walker.mapping_file();
return mapping;
}
private DSLMapWalker buildFileMappingWalker(final List<ParserError> errors, CharStream stream) throws RecognitionException{
DSLMapLexer lexer = new DSLMapLexer(stream);
CommonTokenStream tokens = new CommonTokenStream();
tokens.setTokenSource(lexer);
DSLMapParser parser = new DSLMapParser(tokens);
DSLMapParser.mapping_file_return example = parser.mapping_file();
CommonTree tree = (CommonTree) example.getTree();
// logger.info(tree.toStringTree());
CommonTreeNodeStream nodes = new CommonTreeNodeStream(tree);
DSLMapWalker walker = new DSLMapWalker(nodes);
errors.addAll( lexer.getErrors() );
errors.addAll( parser.getErrors() );
return walker;
}
}