gmail_sendmail.groovy

def sendMail(user, pw, from, recipients, subject, body) {
    new AntBuilder().mail(
        mailhost: 'smtp.gmail.com',
        mailport: '465',
        ssl: 'on',
        user: user,
        password: pw,
        from: from,
        toList: recipients,
        subject: subject,
        message: body
    )
}

sendMail('GMAIL_USERNAME', 'GMAIL_PASSWORD', 'from@domain.com', 'sendto@domain.com', 'Subject可以用中文', 'Content可以用中文, too')