bug fixed for sql parser

src/main/java/com/alibaba/druid/sql/ast/SQLStatementImpl.java

@@ -15,7 +15,6 @@
  */
 package com.alibaba.druid.sql.ast;
 
-import com.alibaba.druid.sql.dialect.oracle.visitor.OracleASTVisitor;
 import com.alibaba.druid.sql.visitor.SQLASTVisitor;
 
 public abstract class SQLStatementImpl extends SQLObjectImpl implements SQLStatement {
@@ -34,8 +33,4 @@ public abstract class SQLStatementImpl extends SQLObjectImpl implements SQLState
     protected void accept0(SQLASTVisitor visitor) {
         throw new UnsupportedOperationException(this.getClass().getName());
     }
-
-    protected void accept0(OracleASTVisitor visitor) {
-        throw new UnsupportedOperationException(this.getClass().getName());
-    }
 }

src/main/java/com/alibaba/druid/sql/ast/expr/SQLCurrentOfCursorExpr.java

@@ -29,6 +29,10 @@ public class SQLCurrentOfCursorExpr extends SQLExprImpl {
 
     }
 
+    public SQLCurrentOfCursorExpr(SQLName cursorName){
+        this.cursorName = cursorName;
+    }
+
     public SQLName getCursorName() {
         return cursorName;
     }