Question

我正在开发一个使用JDBC和Java Mail的java项目。我正在尝试将运行我的SQL语句的输出发送到我的电子邮件。

问题是msg.setText（），这是将文本插入电子邮件正文的方法，是静态的。所以，我不能把我在那里执行SQL语句的任何方法作为参数，因为我不能对非静态方法进行静态引用。

如何将输出（控制台中的结果）发送到电子邮件地址？

控制台的预期输出是：

ALLDONE: 0
COUNT(1): 0
IN_AC_IND: 0
Billing Count(1): 0
Signon: 0

因此，在电子邮件的正文中将是整个邮件。

The code: 
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement; 
import java.util.Date;
import java.util.Properties;
import javax.mail.Authenticator;
import javax.mail.Message;
import javax.mail.MessagingException;
import javax.mail.PasswordAuthentication;
import javax.mail.Session;
import javax.mail.Transport;
import javax.mail.internet.AddressException;
import javax.mail.internet.InternetAddress;
import javax.mail.internet.MimeMessage;

public class test {

    Connection conn; 

    public static void main (String[] args) {

    new test();
     email();

      } // end of main class

    public static void email(){
        final String SSL_FACTORY = "javax.net.ssl.SSLSocketFactory";
          // Get a Properties object
             Properties props = System.getProperties();
             props.setProperty("mail.smtp.host", "smtp.gmail.com");
             props.setProperty("mail.smtp.socketFactory.class", SSL_FACTORY);
             props.setProperty("mail.smtp.socketFactory.fallback", "false");
             props.setProperty("mail.smtp.port", "587");
             props.setProperty("mail.smtp.socketFactory.port", "587");
             props.put("mail.smtp.auth", "true");
             props.put("mail.debug", "true");
             props.put("mail.store.protocol", "pop3");
             props.put("mail.transport.protocol", "smtp");
             final String username = "user";//
             final String password = "pass";
             try{
             Session session = Session.getDefaultInstance(props, 
                                  new Authenticator(){
                                     protected PasswordAuthentication getPasswordAuthentication() {
                                        return new PasswordAuthentication(username, password);
                                     }});

           // -- Create a new message --
             Message msg = new MimeMessage(session);

          // -- Set the FROM and TO fields --
             msg.setFrom(new InternetAddress("email"));
             msg.setRecipients(Message.RecipientType.TO, 
                              InternetAddress.parse("email",false));
             msg.setSubject("Daily Activity Report");
             msg.setText("This is a test email ");
             msg.setSentDate(new Date());
             Transport.send(msg);
             System.out.println("Message sent.");

          }catch (MessagingException e){ System.out.println("Error: " + e);}
    }

    public test() {
        try
        {

            Class.forName("value");
            conn = DriverManager.getConnection("value", "value" , "value");
            execute();
            conn.close();

        }catch (ClassNotFoundException ex) {System.err.println(ex.getMessage());
        }catch (SQLException ex)           {System.err.println(ex.getMessage());}
        }

    public void execute() {
        method();
        // someOtherMethod();
        method2();
        method3();
    }

    public void method(){
    String query = "SELECT ALLDONE FROM table";
    try{
        Statement st = conn.createStatement();
        ResultSet rs = st.executeQuery(query);
        while (rs.next())
        {
            String s = rs.getString ("ALLDONE");
            System.out.println("ALLDONE: " + s);
        }
    }catch (SQLException ex){
        System.err.println(ex.getMessage());
    }

Answer 1

你需要让“method”返回一个String。这是它的重写版本：

public String method()
{
    String query = "SELECT ALLDONE FROM table";
    StringBuilder retval = new StringBuilder("");
    try
    {
        Statement st = conn.createStatement();
        ResultSet rs = st.executeQuery(query);
        while (rs.next())
        {
            String s = rs.getString("ALLDONE");
            retval.append(s + "\n");
            System.out.println("ALLDONE: " + s);
        }
    }
    catch (SQLException ex)
    {
        System.err.println(ex.getMessage());
    }
    return retval.toString();
}

请注意，除了使用System.out.println将结果打印到控制台之外，我们还将它们添加到StringBuilder中，然后将它们作为String返回。

如何将结果从控制台输出到电子邮件？

1 个答案: