最近寫專案考慮把一些執行時候出現的異常傳送郵箱，這樣可以隨時監控錯誤，網上看可以用log4J傳送錯誤日誌到郵箱，現在把這種方式記錄下來，以備下次用

1.log4j方式

需要jar包

<dependency>
  <groupId>javax.mail</groupId>
  <artifactId>mail</artifactId>
  <version>1.4.7</version>
</dependency>

<!--log4J-->
<dependency>
  <groupId>
 
org.slf4j</groupId>
  <artifactId>slf4j-log4j12</artifactId>
  <version>${slf4j.version}</version>
</dependency>

log4j.rootLogger =MAIL 

#傳送錯誤郵件
log4j.appender.MAIL=org.apache.log4j.net.SMTPAppender  
log4j.appender.MAIL.Threshold=ERROR 
 
log4j.appender.MAIL.BufferSize=10
log4j.appender.MAIL.From=*****@126.com
log4j.appender.MAIL.SMTPHost=smtp.126.com
log4j.appender.MAIL.SMTPUsername=*****
log4j.appender.MAIL.SMTPPassword=*******
log4j.appender.MAIL.SMTPDebug=true  
log4j.appender.MAIL.Subject=Log4JErrorMessage
log4j.appender.MAIL.To=
 
*****@163.com
log4j.appender.MAIL.layout=org.apache.log4j.PatternLayout
log4j.appender.MAIL.layout.ConversionPattern=[framework]%d - %c -%-4r[%t]%-5p %c %x -%m%n</span></strong> 

自己測試，每次會發送三次郵件，一次是自己做aop異常捕獲的，還有兩次是druid列印的錯誤日誌，有點繁瑣。決定用第二種方式。

2.自定義郵件傳送util

這個還是需要上面的mail包，下面是我自定義的異常郵件傳送工具

import org.springframework.mail.MailException;
import org.springframework.mail.javamail.JavaMailSenderImpl;
import org.springframework.mail.javamail.MimeMessageHelper;
import javax.mail.MessagingException;
import javax.mail.internet.MimeMessage;
import java.io.UnsupportedEncodingException;
import java.util.Properties;
/**
 * Description
 *
 * @author wangsong
 * @date 19:39 2018/1/30
 */
public class ErrorLogMail {
    private static final String HOST = "smtp.126.com";
    private static final Integer PORT = 25;
    private static final String USERNAME = "***@126.com";
    private static final String PASSWORD = "****";
    private static final String EMAILFORM = "***@126.com";
    private static JavaMailSenderImpl mailSender = createMailSender();
/**
     * 郵件傳送器
     *
     * @return 配置好的工具
     */
private static JavaMailSenderImpl createMailSender() {
        JavaMailSenderImpl sender = new JavaMailSenderImpl();
sender.setHost(HOST);
sender.setPort(PORT);
sender.setUsername(USERNAME);
sender.setPassword(PASSWORD);
sender.setDefaultEncoding("Utf-8");
Properties p = new Properties();
p.setProperty("mail.smtp.timeout", "25000");
p.setProperty("mail.smtp.auth", "false");
sender.setJavaMailProperties(p);
        return sender;
}
    /**
     * 傳送郵件
     * @param html 傳送內容
     * @throws MessagingException 異常
     * @throws UnsupportedEncodingException 異常
     */
public static void sendHtmlMail( String html)  {
        try {
            MimeMessage mimeMessage = mailSender.createMimeMessage();
// 設定utf-8或GBK編碼，否則郵件會有亂碼
MimeMessageHelper messageHelper = new MimeMessageHelper(mimeMessage, true, "UTF-8");
messageHelper.setFrom(EMAILFORM, "wangsong");
messageHelper.setTo("******@163.com");
messageHelper.setSubject("ErrorLog");
messageHelper.setText(html, true);
mailSender.send(mimeMessage);
} catch (MessagingException e) {
            e.printStackTrace();
} catch (UnsupportedEncodingException e) {
            e.printStackTrace();
} catch (MailException e) {
            e.printStackTrace();
}
    }

logger.error(pjp.getSignature() + " error ", e);
//不可知異常，傳送郵件ErrorLogMail.sendHtmlMail("時間："+new Date()+"方法："+pjp.getSignature()+"原因："+e.toString());