Question

I configured JavaMail with Spring framework using JavaMailSenderImpl in my application.Actually I tried to load mailing properties from database and done little bit changes at spring config.xml file.
But i got error

“Initialization of bean failed; nested exception is
org.springframework.beans.TypeMismatchException: Failed to convert
property value of type [com.core.springexamples.UCMSMailImpl] to
required type [org.springframework.mail.MailSender] for property
‘mailSender’; nested exception is java.lang.IllegalArgumentException:
Cannot convert value of type [com.core.springexamples.UCMSMailImpl] to
required type [org.springframework.mail.MailSender] for property
‘mailSender’: no matching editors or conversion strategy found”

whatever changes are implemented in my application,those are mentioned in below.

Step 1:

<bean id="javaMailImpl" class="org.springframework.mail.javamail.JavaMailSenderImpl"></bean>

Step 2:-

<bean id="mailSender" class="com.core.springexamples.UCMSMailImpl" scope="prototype" init-method="configuredProperties">
    <property name="javaMailImpl" ref="javaMailImpl"></property>
</bean>

com.core.springexamples.UCMSMailImpl:-

public class UCMSMailImpl {
    private JavaMailSenderImpl javaMailImpl;
    private ConfigDAO configDAO;

    public  void configuredProperties(){
        System.out.println("UCMSMailImpl::configuredProperties");
        Properties props=new Properties();
    String[] mildata=configDAO.getMailingPropData();
        props.put("mail.smtp.auth", mildata[0]);
        props.put("mail.smtp.starttls.enable", mildata[2]);
        props.put("mail.smtp.host", mildata[3]);
        props.put("mail.smtp.port", mildata[4]);
        props.put("mail.smtp.host", mildata[5]);
        props.put("username", mildata[6]);
        props.put("password",mildata[7]);
        getJavaMailImpl().setJavaMailProperties(props);

    }
    public JavaMailSenderImpl getJavaMailImpl() {
        return javaMailImpl;
    }
    public void setJavaMailImpl(JavaMailSenderImpl javaMailImpl) {
        this.javaMailImpl = javaMailImpl;
    }
    public void setConfigDAO(ConfigDAO configDAO){
    this.configDAO=configDAO;
    }
    public ConfigDAO getConfigDAO(){
    return configDAO;
    }

Step 3:-I am trying send the mail from MailSender.send using UCMSMailImpl java class.I refered the UCMSMailImpl bean.

<bean id="sendMail" class="com.core.springexamples.JavaMailing">
    <property name="mailSender" ref="mailSender"></property>

</bean>


public class JavaMailing {
    private MailSender mailSender;


    public void sendMail(String from,String to,String text,String subject){
        SimpleMailMessage message = new SimpleMailMessage();
                message.setFrom(from);
        message.setTo(to);
        message.setSubject(subject);
        message.setText(text);
        mailSender.send(message);   

    }

    /**
     * @return the mailSender
     */
    public MailSender getMailSender() {
        return mailSender;
    }

    /**
     * @param mailSender the mailSender to set
     */
    public void setMailSender(MailSender mailSender) {
        this.mailSender = mailSender;
    }

Step 4:- I trying to test the sendMail bean

ApplicationContext context =new ClassPathXmlApplicationContext("applicationContext-mail.xml");
    JavaMailing m=(JavaMailing)context.getBean("sendMail");
   m.sendMail("[e-mail]", "[e-mail]", "TEST MAIL", "TEST MAIL");

But i got exception is TypeMismatchException: Failed to convert property value of type [com.core.springexamples.UCMSMailImpl] to required type [org.springframework.mail.MailSender] for property

Please help me.

Answer 1

You cannot assign a class to an interface, if it doesn’t implement the interface. UCMSMailImpl does not implement MailSender. Keep the rest as it is and change your UCMSMailImpl like this:

public class UCMSMailImpl implements MailSender {

    private JavaMailSenderImpl javaMailImpl;
    private ConfigDAO configDAO;

    // do your property initialization
    // ...

    // implement interface methods

    void send(SimpleMailMessage simpleMessage) throws MailException {
        this.javaMailImpl.send(simpleMessage);
    }

    void send(SimpleMailMessage[] simpleMessages) throws MailException {
        this.javaMailImpl.send(simpleMEssages);
    }

}

If you cannot change UCMSMailImpl, extend it:

public class MyUCMSMailImpl extends UCMSMailImpl implements MailSender {

    void send(SimpleMailMessage simpleMessage) throws MailException {
        this.getgetJavaMailImpl().send(simpleMessage);
    }

    void send(SimpleMailMessage[] simpleMessages) throws MailException {
        this.getgetJavaMailImpl().send(simpleMEssages);
    }

}

and change your configuration:

<bean id="mailSender" class="your.package.MyUCMSMailImpl" scope="prototype" init-method="configuredProperties">
    <property name="javaMailImpl" ref="javaMailImpl"></property>
</bean>