动态更改配置文件

环境

邮件发送人要动态设置，登陆人是谁发送人就是谁。
这就需要配置文件可修改

配置文件

SpringMVC

properties

prop.file=xxx.properties #本properties配置文件的名字

email.host=smtp.163.com
email.port=25
email.username=xxx@163.com
email.password=xxx
email.smtpAuth=true
email.smtpConnectiontimeout=800000
email.smtpTimeout=800000
email.smtpwritetimeout=800000
email.smtp.starttls.enable=true

<util:properties id="config" location="classpath:xxx.properties" />

<bean id="javaMailSender" class="org.springframework.mail.javamail.JavaMailSenderImpl">
    <property name="host" value="#{config['email.host']}"/>
    <property name="port" value="#{config['email.port']}"/>
    <property name="username" value="#{config['email.username']}"/>
    <property name="password" value="#{config['email.password']}"/>
    <property name="javaMailProperties">
        <props >
            <prop key="mail.smtp.auth">#{config['email.smtpAuth']}prop>
            <prop key="mail.smtp.connectiontimeout">#{config['email.smtpConnectiontimeout']}prop>
            <prop key="mail.smtp.timeout">#{config['email.smtpTimeout']}prop>
            <prop key="mail.smtp.writetimeout">#{config['email.smtpwritetimeout']}prop>

        props>
    property>
bean>

SpringBoot

1. 类似上面springmvc

appliction.yml

spring:
  profiles:
    active: email  #引入另外一个同路径下yml配置文件，该配置文件必须以application-开头
    #配置邮件发送
  mail:
      host: smtp.qiye.163.com # 163邮箱smtp主机
      port: 25 #qq端口号465或587
#      username: xxx
#      password: xxx # 这里QQ邮箱开通POP3/SMTP提供的授权码，如果邮箱服务商没有授权码，可以使用密码代替
      protocol: smtp
      default-encoding: UTF-8

appliction-email.yml

prop:
  file: application-email.yml
#spring
spring:
  #配置邮件发送
  mail:
    username: xxx
    password: xxx

2.

appliction.yml

spring:
  #配置邮件发送
  mail:
      host: smtp.qiye.163.com # 163邮箱smtp主机
      port: 25 #qq端口号465或587
      username: xxx
      password: xxx # 这里QQ邮箱开通POP3/SMTP提供的授权码，如果邮箱服务商没有授权码，可以使用密码代替
      protocol: smtp
      default-encoding: UTF-8

方法

SpringMVC

// 或${prop.file}
public MyResult setSMTPInfo(SMTPInfo smtpInfo,@Value("#{config['prop.file']}") String propfileName){
     
	Resource  propertiesFile = new ClassPathResource(propfileName);
	Properties fileProp = new Properties();
	try {
     
		File outfile = propertiesFile.getFile();
		fileProp.load(new FileInputStream(outfile));
		
		javaMailSender.setHost(smtpInfo.getHost());
		fileProp.setProperty("email.host", smtpInfo.getHost());
		
		javaMailSender.setPort(smtpInfo.getPort());
		fileProp.setProperty("email.port", ""+smtpInfo.getPort());
		
		javaMailSender.setUsername(smtpInfo.getUsername());
		fileProp.setProperty("email.username", ""+smtpInfo.getUsername());
		
		javaMailSender.setPassword(smtpInfo.getPassword());
		fileProp.setProperty("email.password", ""+smtpInfo.getPassword());
		
		Properties prop = new Properties();
		prop.setProperty("mail.smtp.auth", smtpInfo.getSmtpAuth());
		javaMailSender.setJavaMailProperties(prop);
		fileProp.setProperty("email.smtpAuth", ""+smtpInfo.getSmtpAuth());
		
		 OutputStream fos = new FileOutputStream(outfile);
		 fileProp.store(fos, "file updated on" + new Date());
	} catch (IOException e) {
     
		logger.error(e.getMessage(), e);
		return new MyResult(-1,e.getMessage());
	}
	return new MyResult(1,"已成功设置邮件发送服务器!");
	
}

上面为接口，可写页面做修改，这些信息修改是修改的编译后文件内容，所以重新发布后，这些配置信息还为原文件内容，除非发布前将配置信息更改为对应的修改信息。

SpringBoot

1. 类似上面springmvc

@Autowired
private JavaMailSenderImpl mailSender;

/**
* 后加的防止题目过长并且进行全局定义
*/
static {
     
   System.setProperty("mail.mime.splitlongparameters", "false");
   System.setProperty("mail.mime.charset", "UTF-8");
}

/**
 * 发送简单邮件测试
 */
public void sendMail(User user) {
     
	setSMTPInfo(user);
    MimeMessage mimeMessage = mailSender.createMimeMessage();
    MimeMessageHelper helper = new MimeMessageHelper(mimeMessage, true);
    try {
     
        helper.setFrom(mailSender.getUsername());
        // 或new String[]{"xxx"}
        helper.setTo("xxx");
        helper.setSubject("测试邮件");
        helper.setText("测试邮件内容");
    } catch (MessagingException e) {
     
        e.printStackTrace();
    }
    mailSender.send(mimeMessage);
}

@Value("${prop.file}")
private String propfileName; // 读取配置文件
public void setSMTPInfo(User user){
     
    Resource propertiesFile = new ClassPathResource(propfileName);
    Properties fileProp = new Properties();
    try {
     
        File outfile = propertiesFile.getFile();
        fileProp.load(new FileInputStream(outfile));
        if (StringUtils.isNotBlank(user.getEmail())
                && StringUtils.isNotBlank(user.getEmailPassword())){
     
            mailSender.setUsername(user.getEmail());
            fileProp.setProperty("spring.mail.username", user.getEmail());
			mailSender.setPassword(EnOrDecryptionUtil.base64Decrypt(user.getEmailPassword()));
            fileProp.setProperty("spring.mail.password", EnOrDecryptionUtil.base64Decrypt(user.getEmailPassword()));
            
            OutputStream fos = new FileOutputStream(outfile);
            fileProp.store(fos, "file updated on" + new Date());
        }
    } catch (IOException e) {
     
        log.error(e.getMessage(), e);
        e.printStackTrace();
    }
    log.info("已成功设置邮件发送服务器!");
}

上面SpringBoot 使用的方法和SpringMVC其实是一致的，所以在SpringBoot配置那要将更改的信息和不更改的信息分开，否则使用该方法后，再次启动项目会报错，除非启动前mvn clean或者rebuild。因编译后的配置文件中被更改的信息模式会被更改为properties格式，不能正常使用。

2.

设置一个公共替换发件人设置的方法setSMTPInfo(sysUser),每次调用发送邮件方法时调用该功能方法。因发送邮箱后缀是一样的，所以不需要重新设置主机、端口号、协议。

// import org.springframework.mail.javamail.JavaMailSenderImpl;
@Autowired
private JavaMailSenderImpl mailSender;
public void setSMTPInfo(User user){
     
	if (StringUtils.isNotBlank(user.getEmail())
	         && StringUtils.isNotBlank(user.getEmailPassword())) {
     
	     mailSender.setUsername(user.getEmail());
	     mailSender.setPassword(EnOrDecryptionUtil.base64Decrypt(user.getEmailPassword()));
	     log.info("已成功设置邮件发送服务器!");
	}else{
     
	     mailSender.setUsername("xxx");
	     mailSender.setPassword(EnOrDecryptionUtil.base64Decrypt("xxx"));
	     log.info("登录人邮箱或者密码为空,默认xxx为发送人!");
	
	 }
}

注：项目重新发布后，配置文件还是原有的配置信息，不为更改后的；

邮箱参数含义

API

参数	类型	解释
mail.smtp.connectiontimeout	int	Socket connection timeout value in milliseconds. This timeout is implemented by java.net.Socket. Default is infinite timeout.
mail.smtp.timeout	int	Socket read timeout value in milliseconds. This timeout is implemented by java.net.Socket. Default is infinite timeout.
mail.smtp.writetimeout	int	Socket write timeout value in milliseconds. This timeout is implemented by using a java.util.concurrent.ScheduledExecutorService per connection that schedules a thread to close the socket if the timeout expires. Thus, the overhead of using this timeout is one thread per connection. Default is infinite timeout.

因为上面几个配置```连接时间限制、邮件接收时间限制、邮件接收时间限制```默认时间为无穷大，所以若不配置，则邮箱发送的等待时间可能是无穷大，出现异常后（比如邮箱服务器繁忙）客户端有可能永远在等待往服务器读写消息。这里涉及到跟服务器间的socket交互。*如下图，JavaMail在socket读写过程中有可能无限等待下去