enhance sql parser

src/main/java/com/alibaba/druid/sql/parser/SQLParser.java

@@ -28,6 +28,10 @@ public class SQLParser {
         this.lexer = lexer;
     }
 
+    public final Lexer getLexer() {
+        return lexer;
+    }
+
     protected boolean identifierEquals(String text) {
         return lexer.token() == Token.IDENTIFIER && lexer.stringVal().equalsIgnoreCase(text);
     }

src/main/java/com/alibaba/druid/sql/parser/SQLSelectParser.java

@@ -102,7 +102,7 @@ public class SQLSelectParser extends SQLParser {
         return selectQuery;
     }
 
-    protected SQLSelectQuery query() throws ParserException {
+    public SQLSelectQuery query() throws ParserException {
         if (lexer.token() == Token.LPAREN) {
             lexer.nextToken();