没有可用的“java.lang.String”类型的合格 bean：预计至少有 1 个有资格作为自动装配候选者的 bean。 依赖注解：

Question

I am using spring starter-email service to send emails to the users when there will be new job posting: I am following this article from geeks for geeks, I feel issue is something with @Value annotation, but unable to get it but while running mvn-clean install, I am getting below error

Caused by: org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'jobController' defined in file [C:\Users\ViShah\IdeaProjects\avatureJobSearch\target\classes\com\avature\controller\JobController.class]: Unsatisfied dependency expressed through constructor parameter 0; nested exception is org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'jobService' defined in file [C:\Users\ViShah\IdeaProjects\avatureJobSearch\target\classes\com\avature\service\JobService.class]: Unsatisfied dependency expressed through constructor parameter 2; nested exception is org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'emailService' defined in file [C:\Users\ViShah\IdeaProjects\avatureJobSearch\target\classes\com\avature\service\EmailService.class]: Unsatisfied dependency expressed through constructor parameter 0; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type 'java.lang.String' available: expected at least 1 bean which qualifies as autowire candidate. Dependency annotations: {}
    at org.springframework.beans.factory.support.ConstructorResolver.createArgumentArray(ConstructorResolver.java:800) ~[spring-beans-5.3.20.jar:5.3.20]
    at org.springframework.beans.factory.support.ConstructorResolver.autowireConstructor(ConstructorResolver.java:229) ~[spring-beans-5.3.20.jar:5.3.20]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.autowireConstructor(AbstractAutowireCapableBeanFactory.java:1372) ~[spring-beans-5.3.20.jar:5.3.20]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1222) ~[spring-beans-5.3.20.jar:5.3.20]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:582) ~[spring-beans-5.3.20.jar:5.3.20]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:542) ~[spring-beans-5.3.20.jar:5.3.20]
    at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:335) ~[spring-beans-5.3.20.jar:5.3.20]
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:234) ~[spring-beans-5.3.20.jar:5.3.20]
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:333) ~[spring-beans-5.3.20.jar:5.3.20]
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:208) ~[spring-beans-5.3.20.jar:5.3.20]
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:953) ~[spring-beans-5.3.20.jar:5.3.20]
    at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:918) ~[spring-context-5.3.20.jar:5.3.20]
    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:583) ~[spring-context-5.3.20.jar:5.3.20]
    at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:734) ~[spring-boot-2.7.0.jar:2.7.0]
    at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:408) ~[spring-boot-2.7.0.jar:2.7.0]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:308) ~[spring-boot-2.7.0.jar:2.7.0]
    at org.springframework.boot.test.context.SpringBootContextLoader.loadContext(SpringBootContextLoader.java:132) ~[spring-boot-test-2.7.0.jar:2.7.0]
    at org.springframework.test.context.cache.DefaultCacheAwareContextLoaderDelegate.loadContextInternal(DefaultCacheAwareContextLoaderDelegate.java:99) ~[spring-test-5.3.20.jar:5.3.20]
    at org.springframework.test.context.cache.DefaultCacheAwareContextLoaderDelegate.loadContext(DefaultCacheAwareContextLoaderDelegate.java:124) ~[spring-test-5.3.20.jar:5.3.20]
    ... 67 common frames omitted
Caused by: org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'jobService' defined in file [C:\Users\ViShah\IdeaProjects\avatureJobSearch\target\classes\com\avature\service\JobService.class]: Unsatisfied dependency expressed through constructor parameter 2; nested exception is org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'emailService' defined in file [C:\Users\ViShah\IdeaProjects\avatureJobSearch\target\classes\com\avature\service\EmailService.class]: Unsatisfied dependency expressed through constructor parameter 0; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type 'java.lang.String' available: expected at least 1 bean which qualifies as autowire candidate. Dependency annotations: {}
    at org.springframework.beans.factory.support.ConstructorResolver.createArgumentArray(ConstructorResolver.java:800) ~[spring-beans-5.3.20.jar:5.3.20]
    at org.springframework.beans.factory.support.ConstructorResolver.autowireConstructor(ConstructorResolver.java:229) ~[spring-beans-5.3.20.jar:5.3.20]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.autowireConstructor(AbstractAutowireCapableBeanFactory.java:1372) ~[spring-beans-5.3.20.jar:5.3.20]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1222) ~[spring-beans-5.3.20.jar:5.3.20]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:582) ~[spring-beans-5.3.20.jar:5.3.20]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:542) ~[spring-beans-5.3.20.jar:5.3.20]
    at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:335) ~[spring-beans-5.3.20.jar:5.3.20]
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:234) ~[spring-beans-5.3.20.jar:5.3.20]
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:333) ~[spring-beans-5.3.20.jar:5.3.20]
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:208) ~[spring-beans-5.3.20.jar:5.3.20]
    at org.springframework.beans.factory.config.DependencyDescriptor.resolveCandidate(DependencyDescriptor.java:276) ~[spring-beans-5.3.20.jar:5.3.20]
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1389) ~[spring-beans-5.3.20.jar:5.3.20]
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1309) ~[spring-beans-5.3.20.jar:5.3.20]
    at org.springframework.beans.factory.support.ConstructorResolver.resolveAutowiredArgument(ConstructorResolver.java:887) ~[spring-beans-5.3.20.jar:5.3.20]
    at org.springframework.beans.factory.support.ConstructorResolver.createArgumentArray(ConstructorResolver.java:791) ~[spring-beans-5.3.20.jar:5.3.20]
    ... 85 common frames omitted
Caused by: org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'emailService' defined in file [C:\Users\ViShah\IdeaProjects\avatureJobSearch\target\classes\com\avature\service\EmailService.class]: Unsatisfied dependency expressed through constructor parameter 0; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type 'java.lang.String' available: expected at least 1 bean which qualifies as autowire candidate. Dependency annotations: {}
    at org.springframework.beans.factory.support.ConstructorResolver.createArgumentArray(ConstructorResolver.java:800) ~[spring-beans-5.3.20.jar:5.3.20]
    at org.springframework.beans.factory.support.ConstructorResolver.autowireConstructor(ConstructorResolver.java:229) ~[spring-beans-5.3.20.jar:5.3.20]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.autowireConstructor(AbstractAutowireCapableBeanFactory.java:1372) ~[spring-beans-5.3.20.jar:5.3.20]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1222) ~[spring-beans-5.3.20.jar:5.3.20]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:582) ~[spring-beans-5.3.20.jar:5.3.20]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:542) ~[spring-beans-5.3.20.jar:5.3.20]
    at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:335) ~[spring-beans-5.3.20.jar:5.3.20]
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:234) ~[spring-beans-5.3.20.jar:5.3.20]
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:333) ~[spring-beans-5.3.20.jar:5.3.20]
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:208) ~[spring-beans-5.3.20.jar:5.3.20]
    at org.springframework.beans.factory.config.DependencyDescriptor.resolveCandidate(DependencyDescriptor.java:276) ~[spring-beans-5.3.20.jar:5.3.20]
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1389) ~[spring-beans-5.3.20.jar:5.3.20]
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1309) ~[spring-beans-5.3.20.jar:5.3.20]
    at org.springframework.beans.factory.support.ConstructorResolver.resolveAutowiredArgument(ConstructorResolver.java:887) ~[spring-beans-5.3.20.jar:5.3.20]
    at org.springframework.beans.factory.support.ConstructorResolver.createArgumentArray(ConstructorResolver.java:791) ~[spring-beans-5.3.20.jar:5.3.20]
    ... 99 common frames omitted
Caused by: org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type 'java.lang.String' available: expected at least 1 bean which qualifies as autowire candidate. Dependency annotations: {}
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.raiseNoMatchingBeanFound(DefaultListableBeanFactory.java:1799) ~[spring-beans-5.3.20.jar:5.3.20]
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1355) ~[spring-beans-5.3.20.jar:5.3.20]
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1309) ~[spring-beans-5.3.20.jar:5.3.20]
    at org.springframework.beans.factory.support.ConstructorResolver.resolveAutowiredArgument(ConstructorResolver.java:887) ~[spring-beans-5.3.20.jar:5.3.20]
    at org.springframework.beans.factory.support.ConstructorResolver.createArgumentArray(ConstructorResolver.java:791) ~[spring-beans-5.3.20.jar:5.3.20]
    ... 113 common frames omitted

Below is my email service

import com.entity.Job;
import com.entity.User;
import com.repository.UserRepository;
import lombok.AllArgsConstructor;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.mail.javamail.JavaMailSender;
import org.springframework.mail.javamail.MimeMessageHelper;
import org.springframework.stereotype.Service;

import javax.mail.MessagingException;
import javax.mail.internet.MimeMessage;
import java.util.List;

@Service
@Slf4j
@AllArgsConstructor
public class EmailService {

    @Value(value = "${spring.mail.username}")
    String sender;
    final String HOST = "http://localhost:8080/";
    UserRepository userRepository;
    JavaMailSender javaMailSender;

    public void sendEmailWithDetails(Job job){
        List<User> usersList = null;
        if(!job.getPreferredSkills().isEmpty())
            usersList = userRepository.findBySkills(job.getPreferredSkills());
        else{
            usersList = userRepository.findAll();
        }
        for(User user: usersList){
            try {
                generateEmailBodyAndSend(job, user);
            }catch (MessagingException e){
                log.error("error while sending mail to user:"+user.getEmail());
            }
        }
    }

    private void generateEmailBodyAndSend(Job job, User user ) throws MessagingException {
        String body = "<h4>Hey, Found new matching job for you</h4>\n <a href="+HOST+job.getId()+">"+job.getTitle()+"</a>";
        MimeMessage msg = javaMailSender.createMimeMessage();
        MimeMessageHelper helper = new MimeMessageHelper(msg, true);
        helper.setText(body, true);
        helper.setSubject("Notification");
        helper.setFrom(sender);
        helper.setTo(user.getEmail());
        log.info("sending mail to:"+user.getEmail());
        javaMailSender.send(msg);
        log.info("sent mail to:"+user.getEmail());
    }
}

I am using spring-boot 2.7.0 and spring-starter-email 2.7.1 below is my application.properties file:

spring.data.mongodb.uri=mongodb://localhost:27017/jobDB
kafka.bootstrapAddress=localhost:9092
spring.mail.host=smtp.gmail.com
spring.mail.port=587
spring.mail.username=testingmynotification@gmail.com

Answer 1

The problem is that the Lombok constructor won't contain the @Value annotation. Rather, it will look like this:

public EmailService(String sender, UserRepository userRepository, JavaMailSender javaMailSender) {
    this.sender = sender;
    this.userRepository = userRepository;
    this.javaMailSender = javaMailSender;
}

Due to this, Spring doesn't know how to pass the sender field, and so it complains that there's no bean of type String .

The solution is to write your own constructor:

// Add the @Value to the sender parameter
public EmailService(@Value(value = "${spring.mail.username}") String sender, UserRepository userRepository, JavaMailSender javaMailSender) {
    this.sender = sender;
    this.userRepository = userRepository;
    this.javaMailSender = javaMailSender;
}

After that, you can remove the @Value annotation from the sender field (since it's on the constructor) and remove the @AllArgConstructor annotation.