ClassCastException：无法将java.util.Date强制转换为java.sql.Date

Question

您好，我的代码正在抛出ClassCastException。StackTrace显示：

java.lang.ClassCastException: java.util.Date cannot be cast to java.sql.Date
    at com.affiliate.DAO.AffiliateDAO.insertAffiliate(AffiliateDAO.java:48)

即@ ps.setDate（6，（Date）affiliate.getDate（））; 在DAO

以下是我的servlet：

   protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    Affiliate af= new Affiliate();

    af.setFisrtName(request.getParameter("txtFname"));
    af.setLastName(request.getParameter("txtLname"));
    af.setGender(request.getParameter("txtGender"));
    af.setCategory(request.getParameter("txtCategory"));
    String dob=(request.getParameter("txtDob"));
    SimpleDateFormat formatter = new SimpleDateFormat("MM/dd/yyyy");  
    Date date;
    try {
        date = (Date)formatter.parse(dob);
        af.setDate(date);
    } catch (ParseException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }

    af.setAge(Integer.parseInt(request.getParameter("txtAge")));
    af.setAddress(request.getParameter("txtAddr"));
    af.setCountry("India");
    af.setState(request.getParameter("txtState"));
    af.setCity(request.getParameter("txtCity"));
    af.setPinCode(Integer.parseInt(request.getParameter("txtPin")));
    af.setEmailId(request.getParameter("txtEmail"));
    af.setStd(Integer.parseInt(request.getParameter("txtStd")));
    af.setContactNo(Integer.parseInt(request.getParameter("txtPhone")));
    af.setMobileNo(Long.parseLong(request.getParameter("txtMobile"),10));

AffiliateService afs=new AffiliateService();
**afs.createAffiliate(af);**
}

以下是我的DAO：

public void insertAffiliate(Affiliate affiliate){
    String sql="INSERT INTO REGISTER " +"(id,FisrtName,LastName,Gender,Category,DateOfBirth,Age,Address,Country,State,City,PinCode,EmailId,Std,ContactNo,MobileNo)VALUES(?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?)";
    Connection conn = null;

    try {
        **conn = dataSource.createConnection();**
        PreparedStatement ps = conn.prepareStatement(sql);
        ps.setInt(1, affiliate.getId());
        ps.setString(2, affiliate.getFisrtName());
        ps.setString(3, affiliate.getLastName());
        ps.setString(4,affiliate.getGender());
        ps.setString(5, affiliate.getCategory());
        ***ps.setDate(6, (Date) affiliate.getDate());***
        ps.setInt(7, affiliate.getAge());
        ps.setString(8, affiliate.getAddress());
        ps.setString(9,affiliate.getCountry());
        ps.setString(10,affiliate.getState());
        ps.setString(11, affiliate.getCity());
        ps.setInt(12, affiliate.getPinCode());
        ps.setString(13, affiliate.getEmailId());
        ps.setInt(14,affiliate.getStd());
        ps.setInt(15, affiliate.getContactNo());
        ps.setLong(16, affiliate.getMobileNo());

        ps.executeUpdate();
        ps.close();

    } catch (SQLException e) {
        throw new RuntimeException(e);

    } finally {
        if (conn != null) {
            try {
                conn.close();
            } catch (SQLException e) {}
        }
    }
}

以下是我的DTO：

public class Affiliate {

@NotNull
    @Past
    Date date;

public Date getDate() {
        return date;
    }
    public void setDate(Date date) {
        this.date = date;
    }

请在这方面帮助我

Answer 1

由于文档说，将Date在参数setDate()的PreparedStatement需要类型的Date对象java.sql.Date。但是您似乎java.util.Date在Affiliate课堂上使用了对象。

这就是为什么你得到了ClassCastException: java.util.Date cannot be cast to java.sql.Date。

要解决此问题，您需要将类中的Date对象类型更改Affiliate为java.sql.Date或执行此操作

ps.setDate(6, new java.sql.Date(affiliate.getDate().getTime()));