[ADQL] ADQLParser is no longer a Java Interface and ADQLParserFactory does not

exist anymore.

ADQLParser is now a mix between the former ADQLParserFactory and ADQLParser2xx.
All ADQLParser2xx resulting from the compilation of the JavaCC files are
now named ADQLGrammar2xx and implement the new interface ADQLGrammar. The JavaCC
parsers are no longer used directly. This is the role of ADQLParser to simplify
the parser usage and to allow an easy switch between different grammar versions.

Besides, for more clarity in the class organisation, all generated parser
classes have been moved into the package `adql.parser.grammar`.

src/adql/db/DBChecker.java

@@ -38,8 +38,8 @@ import adql.db.exception.UnresolvedColumnException;
 import adql.db.exception.UnresolvedFunctionException;
 import adql.db.exception.UnresolvedIdentifiersException;
 import adql.db.exception.UnresolvedTableException;
-import adql.parser.ParseException;
 import adql.parser.QueryChecker;
+import adql.parser.grammar.ParseException;
 import adql.query.ADQLIterator;
 import adql.query.ADQLObject;
 import adql.query.ADQLQuery;

src/adql/db/FunctionDef.java

@@ -26,11 +26,10 @@ import java.util.regex.Pattern;
 
 import adql.db.DBType.DBDatatype;
 import adql.parser.ADQLParser;
-import adql.parser.ADQLParserFactory;
-import adql.parser.ADQLParserFactory.ADQLVersion;
-import adql.parser.ParseException;
-import adql.parser.Token;
+import adql.parser.ADQLParser.ADQLVersion;
 import adql.parser.feature.LanguageFeature;
+import adql.parser.grammar.ParseException;
+import adql.parser.grammar.Token;
 import adql.query.operand.ADQLOperand;
 import adql.query.operand.function.ADQLFunction;
 import adql.query.operand.function.DefaultUDF;
@@ -334,7 +333,7 @@ public class FunctionDef implements Comparable<FunctionDef> {
 	 *                       	of the ADQL grammar.
 	 */
 	public FunctionDef(final String fctName, final DBType returnType, final FunctionParam[] params) throws ParseException {
-		this(fctName, returnType, params, ADQLParserFactory.DEFAULT_VERSION);
+		this(fctName, returnType, params, ADQLParser.DEFAULT_VERSION);
 	}
 
 	/**
@@ -415,8 +414,8 @@ public class FunctionDef implements Comparable<FunctionDef> {
 
 		// Tokenize the given function name:
 		try {
-			parser = (new ADQLParserFactory()).createParser(adqlVersion == null ? ADQLParserFactory.DEFAULT_VERSION : adqlVersion);
-			tokens = parser.tokenize(fctName);
+			parser = new ADQLParser(adqlVersion);
+			tokens = parser.tokenize(fctName, true);
 		} catch(ParseException ex) {
 			throw new ParseException("Invalid UDF name: " + ex.getMessage());
 		}
@@ -428,7 +427,7 @@ public class FunctionDef implements Comparable<FunctionDef> {
 			throw new ParseException("Invalid UDF name: too many words (a function name must be a single Regular Identifier)!");
 
 		// ...that it is a regular identifier:
-		if (!parser.isRegularIdentifier(tokens[0].image))
+		if (!parser.getGrammarParser().isRegularIdentifier(tokens[0].image))
 			throw new ParseException("Invalid UDF name: \"" + fctName + "\" is not a Regular Identifier!");
 
 		// ...that it is not already an existing ADQL function name:

src/adql/db/STCS.java

@@ -24,7 +24,7 @@ import java.util.regex.Matcher;
 import java.util.regex.Pattern;
 
 import adql.parser.ADQLQueryFactory;
-import adql.parser.ParseException;
+import adql.parser.grammar.ParseException;
 import adql.query.TextPosition;
 import adql.query.operand.ADQLOperand;
 import adql.query.operand.NegativeOperand;

src/adql/db/exception/UnresolvedColumnException.java

@@ -20,7 +20,7 @@ package adql.db.exception;
  */
 
 import adql.db.DBChecker;
-import adql.parser.ParseException;
+import adql.parser.grammar.ParseException;
 import adql.query.operand.ADQLColumn;
 
 /**

src/adql/db/exception/UnresolvedFunctionException.java

@@ -19,7 +19,7 @@ package adql.db.exception;
  * Copyright 2014-2015 - Astronomisches Rechen Institut (ARI)
  */
 
-import adql.parser.ParseException;
+import adql.parser.grammar.ParseException;
 import adql.query.TextPosition;
 import adql.query.operand.function.ADQLFunction;
 

src/adql/db/exception/UnresolvedIdentifiersException.java

@@ -24,7 +24,7 @@ import java.util.ArrayList;
 import java.util.Iterator;
 
 import adql.db.DBChecker;
-import adql.parser.ParseException;
+import adql.parser.grammar.ParseException;
 
 /**
  * This exception is thrown by {@link DBChecker} when several columns, tables,

src/adql/db/exception/UnresolvedJoinException.java

@@ -19,7 +19,7 @@ package adql.db.exception;
  * Copyright 2013-2015 - Astronomisches Rechen Institut (ARI)
  */
 
-import adql.parser.ParseException;
+import adql.parser.grammar.ParseException;
 import adql.query.TextPosition;
 
 /**

src/adql/db/exception/UnresolvedTableException.java

@@ -20,8 +20,7 @@ package adql.db.exception;
  */
 
 import adql.db.DBChecker;
-import adql.parser.ParseException;
-
+import adql.parser.grammar.ParseException;
 import adql.query.from.ADQLTable;
 
 import adql.query.operand.ADQLColumn;

src/adql/db/exception/UnsupportedFeatureException.java

@@ -19,8 +19,8 @@ package adql.db.exception;
  * Copyright 2019 - UDS/Centre de Données astronomiques de Strasbourg (CDS)
  */
 
-import adql.parser.ParseException;
 import adql.parser.feature.LanguageFeature;
+import adql.parser.grammar.ParseException;
 import adql.query.ADQLObject;
 
 /**