Java连接数据库代码

sqlstr3="select name from goods where id=123";
sqlstr1="delete from goods where id =123";
sqlstr2="insert into waster(id,name) VALUES(123,'sqlstr3')";
tx.begin(); //事物提交
DataSource ds=(DataSource)ctx.lookup("MysqlDataSource");
con=ds.getConnection();
stmt=con.createStatement();
//stmt.executeUpdate(sqlstr3);
stmt.executeUpdate(sqlstr1);
stmt.executeUpdate(sqlstr2);
tx.commit(); //事物结束