java发送邮件的具体实现方法源码

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;/**
* 服务器邮箱登录验证
*
* @author MZULE
*
*/
public class MailAuthenticator extends Authenticator {
/**
* 用户名（登录邮箱）
*/
private String username;
/**
* 密码
*/
private String password;
/**
* 初始化邮箱和密码
*
* @param username 邮箱
* @param password 密码
*/
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;
}
}

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;/**
* 发件箱工厂
*
* @author MZULE
*
*/
public class MailSenderFactory {/**
* 服务邮箱
*/
private static SimpleMailSender serviceSms = null;
/**
* 获取邮箱
*
* @param type 邮箱类型
* @return 符合类型的邮箱
*/
public static SimpleMailSender getSender(MailSenderType type) {
if (type == MailSenderType.SERVICE) {
if (serviceSms == null) {
serviceSms = new SimpleMailSender("invisible@126.com",
"hidden");
}
return serviceSms;
}
return null;
}
}

发送邮件，还是观察者模式DEMO里面的代码，呼呼。

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("invisible@qq.com");
recipients.add("invisible@gmail.com");
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();
}
}
}
}
}