我使用 Spring Boot Mail Sender 得到了 SSLHandshakeException

Question

我通過使用 Spring Boot Mail Sender API 得到了 SSLHandshakeException。 我已經指定了我在下面編寫的所有代碼片段和屬性文件。 我應該怎么做才能修復這個錯誤？

記錄錯誤

Mail sending is started
Error occured: Mail server connection failed; nested exception is javax.mail.MessagingException: Could not convert socket to TLS;
  nested exception is:
    javax.net.ssl.SSLHandshakeException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target. Failed messages: javax.mail.MessagingException: Could not convert socket to TLS;
  nested exception is:
    javax.net.ssl.SSLHandshakeException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target

Process finished with exit code 0

應用屬性

spring.mail.host=smtp.gmail.com
spring.mail.port=587
spring.mail.username= myemail
spring.mail.password= mypass
spring.mail.properties.mail.smtp.auth=true
spring.mail.properties.mail.smtp.starttls.enable=true

服務層

@Service
public class SendEmailService {

    @Autowired
    private JavaMailSender javaMailSender;

    public void sendEmail(String to, String body, String topic){
        try {
            System.out.println("Mail sending is started");
            SimpleMailMessage simpleMailMessage = new SimpleMailMessage();
            simpleMailMessage.setFrom("mail@mail.com");
            simpleMailMessage.setTo(to);
            simpleMailMessage.setSubject(topic);
            simpleMailMessage.setText(body);
            javaMailSender.send(simpleMailMessage);
            System.out.println("Mail sending is completed");
        }catch (Exception e){
            System.out.println("Error occured: "+e.getMessage());
        }
    }
}

SpringBootApplication 類

@SpringBootApplication
public class MailSenderApplication {

    @Autowired
    SendEmailService sendEmailService;

    public static void main(String[] args) {
        SpringApplication.run(MailSenderApplication.class, args);
    }

    @EventListener(ApplicationReadyEvent.class)
    public void triggerWhenStarts(){
        sendEmailService.sendEmail("mutlueren01@gmail.com","This e-mail has sending by Spring Boot","Spring Boot Mail Sender TEST");
    }
}

Answer 1

您需要將 SMTP 證書添加到 java 密鑰庫： 如何將 .cer 證書導入 java 密鑰庫？

或禁用證書檢查（不推薦）： 如何繞過 Java 中的 ssl 證書檢查

Answer 2

您可以將您的郵件服務提供商添加為受信任的：

spring.mail.properties.mail.smtp.ssl.trust=smtp.gmail.com

這一行應該添加到 application.properties 文件中。 解決方案適用於 Java 11。