improved sql parser, bug fixed for parent is null

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

@@ -41,8 +41,11 @@ public class SQLServerDeclareStatement extends SQLServerObjectImpl implements SQ
         return items;
     }
 
-    public void setItems(List<SQLDeclareItem> items) {
-        this.items = items;
+    public void addItem(SQLDeclareItem item) {
+        if (item != null) {
+            item.setParent(this);
+        }
+        this.items.add(item);
     }
 
     public String getDbType() {

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

@@ -168,7 +168,7 @@ public class SQLServerStatementParser extends SQLStatementParser {
         
         for (;;) {
             SQLDeclareItem item = new  SQLDeclareItem();
-            declareStatement.getItems().add(item);
+            declareStatement.addItem(item);
             
             item.setName(this.exprParser.name());