简单的java发送邮件程序

    JAVA MAIL是利用现有的邮件账户发送邮件的工具，比如说，我在网易注册一个邮箱账户，通过JAVA Mail的操控，我可以不亲自登录网易邮箱，让程序自动的使用网易邮箱发送邮件。这一机制被广泛的用在注册激活和垃圾邮件的发送等方面。JavaMail可以到http://www.oracle.com/technetwork/java/javamail/index-138643.html进行下载,并将mail.jar添加到classpath即可。如果你使用的是JAVA EE SDK，则可以在C:\glassfishv3\glassfish\modules\mail.jar找到所需的jar包，同样需要添加的classpath。

 

    JAVA邮件发送的大致过程是这样的的：

    1、构建一个继承自javax.mail.Authenticator的具体类，并重写里面的getPasswordAuthentication()方法。此类是用作登录校验的，以确保你对该邮箱有发送邮件的权利。

    2、构建一个properties文件，该文件中存放SMTP服务器地址等参数。

    3、通过构建的properties文件和javax.mail.Authenticator具体类来创建一个javax.mail.Session。Session的创建，就相当于登录邮箱一样。剩下的自然就是新建邮件。

    4、构建邮件内容，一般是javax.mail.internet.MimeMessage对象，并指定发送人，收信人，主题，内容等等。

    5、使用javax.mail.Transport工具类发送邮件。

    下面是封装的代码，注释也比较详细

    1、首先是继承自javax.mail.Authenticator的一个具体类。getPasswordAuthentication()方法也就是构建一个PasswordAuthentication对象并返回，有点费解JAVA Mail这样的设计意图，可能是javax.mail.Authenticator为我们提供了附加的保证安全的验证措施吧。

    

package com.mzule.simplemail;

import javax.mail.Authenticator;
import javax.mail.PasswordAuthentication;

public class MailAuthenticator extends Authenticator {
	private String username;
	private String password;

	public MailAuthenticator(String username, String password) {
		this.username = username;
		this.password = password;
	}

	String getPassword() {
		return password;
	}

	@Override
	protected PasswordAuthentication getPasswordAuthentication() {
		return new PasswordAuthentication(username, password);
	}

	String getUsername() {
		return username;
	}

	public void setPassword(String password) {
		this.password = password;
	}

	public void setUsername(String username) {
		this.username = username;
	}
}

     2、邮件发送类，剩下的步骤都是在这个类实现的。代码中的SimpleMail是封装了邮件主题和内容的一个POJO。觉得在一个方法参数中既包含主题又包含内容，不太合适，故重载了此方法。还有就是因为大多数邮箱的SMTP服务器地址都是可以通过邮箱地址算出来，简单起见，提供了一个不需要SMTP服务器地址的构造器。

 

 

package com.mzule.simplemail;

import java.util.List;
import java.util.Properties;

import javax.mail.MessagingException;
import javax.mail.Session;
import javax.mail.Transport;
import javax.mail.internet.AddressException;
import javax.mail.internet.InternetAddress;
import javax.mail.internet.MimeMessage;
import javax.mail.internet.MimeMessage.RecipientType;


public class SimpleMailSender {

	private final transient Properties props = System.getProperties();
	private transient MailAuthenticator authenticator;

	private transient Session session;

	public SimpleMailSender(final String smtpHostName, final String username,
			final String password) {
		init(username, password, smtpHostName);
	}

	public SimpleMailSender(final String username, final String password) {
		final String smtpHostName = "smtp." + username.split("@")[1];
		init(username, password, smtpHostName);

	}

	private void init(String username, String password, String smtpHostName) {
		props.put("mail.smtp.auth", "true");
		props.put("mail.smtp.host", smtpHostName);
		authenticator = new MailAuthenticator(username, password);
		session = Session.getInstance(props, authenticator);
	}

	public void send(String recipient, String subject, Object content)
			throws AddressException, MessagingException {
		final MimeMessage message = new MimeMessage(session);
		message.setFrom(new InternetAddress(authenticator.getUsername()));
		message.setRecipient(RecipientType.TO, new InternetAddress(recipient));
		message.setSubject(subject);
		message.setContent(content.toString(), "text/html;charset=utf-8");
		Transport.send(message);
	}

	public void send(List<String> recipients, String subject, Object content)
			throws AddressException, MessagingException {
		final MimeMessage message = new MimeMessage(session);
		message.setFrom(new InternetAddress(authenticator.getUsername()));
		final int num = recipients.size();
		InternetAddress[] addresses = new InternetAddress[num];
		for (int i = 0; i < num; i++) {
			addresses[i] = new InternetAddress(recipients.get(i));
		}
		message.setRecipients(RecipientType.TO, addresses);
		message.setSubject(subject);
		message.setContent(content.toString(), "text/html;charset=utf-8");
		Transport.send(message);
	}

	public void send(String recipient, SimpleMail mail)
			throws AddressException, MessagingException {
		send(recipient, mail.getSubject(), mail.getContent());
	}

	public void send(List<String> recipients, SimpleMail mail)
			throws AddressException, MessagingException {
		send(recipients, mail.getSubject(), mail.getContent());
	}

}

         3、调用上面的邮箱发送器，可以构建一个工厂类，工厂类可以封装创建的过程，所以通过读配置文件获取邮箱用户名，密码都会变得十分方便。下面的代码是我在写观察者模式的时候写的，只是简单演示了工厂类。

 

 

package com.mzule.dp.observer.factory;
 
import com.mzule.dp.observer.constant.MailSenderType;
import com.mzule.simplemail.SimpleMailSender;
 
public class MailSenderFactory {
 
    private static SimpleMailSender serviceSms = null;
 
    public static SimpleMailSender getSender(MailSenderType type) {
    if (type == MailSenderType.SERVICE) {
        if (serviceSms == null) {
        serviceSms = new SimpleMailSender("[email protected]",
            "hidden");
        }
        return serviceSms;
    }
    return null;
    }
 
}

         4、发送邮件，还是观察者模式DEMO里面的代码

 

package com.mzule.dp.observer.observer;
 
import java.util.ArrayList;
import java.util.List;
import java.util.Observable;
import java.util.Observer;
 
import javax.mail.MessagingException;
import javax.mail.internet.AddressException;
 
import com.mzule.dp.observer.constant.MailSenderType;
import com.mzule.dp.observer.factory.MailSenderFactory;
import com.mzule.dp.observer.po.Product;
import com.mzule.simplemail.SimpleMailSender;
 
public class ProductPriceObserver implements Observer {
 
    @Override
    public void update(Observable obj, Object arg) {
    Product product = null;
    if (obj instanceof Product) {
        product = (Product) obj;
    }
    if (arg instanceof Float) {
        Float price = (Float) arg;
        Float decrease = product.getPrice() - price;
        if (decrease > 0) {
        // 发送邮件
        SimpleMailSender sms = MailSenderFactory
            .getSender(MailSenderType.SERVICE);
        List<String> recipients = new ArrayList<String>();
        recipients.add("[email protected]");
        recipients.add("[email protected]");
        try {
            for (String recipient : recipients) {
            sms.send(recipient, "价格变动", "您关注的物品"
                + product.getName() + "降价了，由"
                + product.getPrice() + "元降到" + price + "元，降幅达"
                + decrease + "元人民币。赶快购物吧。");
            }
        } catch (AddressException e) {
            e.printStackTrace();
        } catch (MessagingException e) {
            e.printStackTrace();
        }
        }
    }
    }
 
}

         5.以下是原文中缺少的类

package com.mzule.dp.observer.constant;

public class MailSenderType {
   public static MailSenderType SERVICE = null;
}

 

package com.mzule.dp.observer.po;

import java.util.Observable;

public class Product extends Observable{
	public Float getPrice() {
		return price;
	}

	public void setPrice(Float price) {
		this.price = price;
	}

	public Float price;
	public String getName() {
		return name;
	}

	public void setName(String name) {
		this.name = name;
	}

	public String name;
}

 

package com.mzule.simplemail;

public class SimpleMail {
	public String subject;

	public String getSubject() {
		return subject;
	}

	public void setSubject(String subject) {
		this.subject = subject;
	}

	public String getContent() {
		return content;
	}

	public void setContent(String content) {
		this.content = content;
	}

	public String content;
}

         6.发送邮件入口类

package com.mzule.simplemail;

import com.mzule.dp.observer.observer.ProductPriceObserver;
import com.mzule.dp.observer.po.Product;

public class SendMail {

	public static void main(String[] args) {
		ProductPriceObserver server = new ProductPriceObserver();
		Product product = new Product();
		product.setName("杰克琼斯");
		product.setPrice(100F);
		try{
		   server.update(product, 50F);
		}catch(Exception e){
			e.printStackTrace();
		}
	}

}

         8.以上就是完整的发送不带附件的邮件的简单程序，下边的连接是原文地址

 

        原文地址：http://www.cnblogs.com/codeplus/archive/2011/10/30/2229391.html