Java：如何在mysql数据库中添加日期并返回

我需要将当前日期+7天添加到我的sql数据库中，并将其检索回来。我该怎么做

Calendar cal = Calendar.getInstance();
                        cal.add(Calendar.DATE, 7); // add 7 days  
                        int date = cal.get(Calendar.DATE);
                        int month = cal.get(Calendar.MONTH);
                        int year = cal.get(Calendar.YEAR);
                        String newdate = Integer.toString(date);
                        String concat = newdate.concat("-" + Integer.toString(cal.get(Calendar.MONTH)) + "-" + Integer.toString(cal.get(Calendar.YEAR)));

我找到了这个代码

java.util.Date newDate = new Date(result.getDate("VALUEDATE").getTime());

---

您可以直接在MySQL中实现这一点

update your_table
set date_column = date_column + interval 7 day

---

下载Java MySql连接器库并将jar文件添加到构建路径

现在您可以添加到表中

    Connection conn = null;
    try {
        conn =  DriverManager.getConnection("<databaseURLHere>" + "user=<usernameHere>&password=<passwordHere");
        Statement stmt = conn.createStatement();
        String uid = UUID.randomUUID().toString();
        uid = uid.replaceAll("-", "");
        uid = uid.substring(0, 16);
        if (stmt.execute("<sql query here>")) {
        //    rs = stmt.getResultSet();
        }

    } catch (SQLException ex) {
        System.out.println("SQLException: " + ex.getMessage());
        System.out.println("SQLState: " + ex.getSQLState());
        System.out.println("VendorError: " + ex.getErrorCode());
    }

连接连接=null；
试一试{
conn=DriverManager.getConnection（“+”用户=&密码=？”？