bug fixed sql server sql parser. for issue #1678

src/main/java/com/alibaba/druid/sql/dialect/sqlserver/ast/SQLServerTop.java

@@ -16,6 +16,7 @@
 package com.alibaba.druid.sql.dialect.sqlserver.ast;
 
 import com.alibaba.druid.sql.ast.SQLExpr;
+import com.alibaba.druid.sql.ast.expr.SQLIntegerExpr;
 import com.alibaba.druid.sql.dialect.sqlserver.visitor.SQLServerASTVisitor;
 
 public class SQLServerTop extends SQLServerObjectImpl {
@@ -43,6 +44,10 @@ public class SQLServerTop extends SQLServerObjectImpl {
         this.expr = expr;
     }
 
+    public void setExpr(int expr) {
+        this.setExpr(new SQLIntegerExpr(expr));
+    }
+
     public boolean isPercent() {
         return percent;
     }

src/main/java/com/alibaba/druid/sql/dialect/sqlserver/parser/SQLServerExprParser.java

@@ -158,7 +158,12 @@ public class SQLServerExprParser extends SQLExprParser {
                 lexer.nextToken();
             }
 
-            top.setExpr(primary());
+            if (lexer.token() == Token.LITERAL_INT) {
+                top.setExpr(lexer.integerValue().intValue());
+                lexer.nextToken();
+            } else {
+                top.setExpr(primary());
+            }
 
             if (paren) {
                 accept(Token.RPAREN);