refactor

src/main/java/com/alibaba/druid/sql/ast/statement/SQLAlterTableItem.java

@@ -0,0 +1,7 @@
+package com.alibaba.druid.sql.ast.statement;
+
+import com.alibaba.druid.sql.ast.SQLObject;
+
+public interface SQLAlterTableItem extends SQLObject {
+
+}

src/main/java/com/alibaba/druid/sql/ast/statement/SQLAlterTableStatement.java

@@ -0,0 +1,31 @@
+package com.alibaba.druid.sql.ast.statement;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import com.alibaba.druid.sql.ast.SQLStatementImpl;
+
+public class SQLAlterTableStatement extends SQLStatementImpl {
+
+    private static final long       serialVersionUID = 1L;
+
+    private SQLExprTableSource      tableSource;
+    private List<SQLAlterTableItem> items            = new ArrayList<SQLAlterTableItem>();
+
+    public List<SQLAlterTableItem> getItems() {
+        return items;
+    }
+
+    public void setItems(List<SQLAlterTableItem> items) {
+        this.items = items;
+    }
+
+    public SQLExprTableSource getTableSource() {
+        return tableSource;
+    }
+
+    public void setTableSource(SQLExprTableSource tableSource) {
+        this.tableSource = tableSource;
+    }
+
+}