Java使用Velocity模板发送HTML格式邮件并解决中文乱码问题

不念不忘少年蓝@ 2022-07-11 06:58 405阅读 0赞

项目中经常会遇到发送邮件的问题，有时还需要发送html格式的邮件，如果直接在java文件硬编码写html，那么维护起来将会非常麻烦，利用Velocity模板引擎可以解决这个问题，使得业务处理和视图渲染相分离，方便维护。

项目依赖：

<properties>
        <springframework>4.2.6.RELEASE</springframework>
    </properties>
    
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-beans</artifactId>
        <version>${springframework}</version>
    </dependency>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-context</artifactId>
        <version>${springframework}</version>
    </dependency>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-context-support</artifactId>
        <version>${springframework}</version>
        <exclusions>
            <exclusion>
                <groupId>commons-logging</groupId>
                <artifactId>commons-logging</artifactId>
            </exclusion>
        </exclusions>
    </dependency>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-core</artifactId>
        <version>${springframework}</version>
    </dependency>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-test</artifactId>
        <version>${springframework}</version>
    </dependency>
    <dependency>
        <groupId>org.apache.velocity</groupId>
        <artifactId>velocity</artifactId>
        <version>1.7</version>
    </dependency>
    <dependency>
        <groupId>com.sun.mail</groupId>
        <artifactId>javax.mail</artifactId>
        <version>1.5.5</version>
    </dependency>

接下写一个服务类，提供发送邮件的功能：

public class SendEmailService { 
    
        private JavaMailSender sender;
    
        private VelocityEngine velocityEngine;
    
        public void sendEmail() {
            MimeMessagePreparator preparator = new MimeMessagePreparator() {
                @Override
                public void prepare(MimeMessage mimeMessage) throws Exception {
                    //设置内容显示的编码格式
                    MimeMessageHelper helper = new MimeMessageHelper(mimeMessage, "UTF-8");
                    helper.setTo("wang704987562@vip.qq.com");
                    helper.setFrom("输入你的发送邮箱地址");
                    Map modal = new HashMap<>();
                    modal.put("userName", "wzx");
                    modal.put("emailAddress", "wang704987562@vip.qq.com");
                    String content = VelocityEngineUtils.mergeTemplateIntoString(velocityEngine, "email_tempalte.vm", "UTF-8", modal);
                    helper.setSubject("邮件主题");
                    helper.setText(content, true);
                }
            };
            this.sender.send(preparator);
        }
    
    
        public void setSender(JavaMailSender sender) {
            this.sender = sender;
        }
    
        public void setVelocityEngine(VelocityEngine velocityEngine) {
            this.velocityEngine = velocityEngine;
        }
    }

添加一个简单的模板文件：

<html>
        <body>
            <h3>Hi ${userName}, welcome to the Chipping Sodbury On-the-Hill message boards!</h3>
    
            <div>
                Your email address is ${emailAddress}.
            </div>
        </body>
    </html>

在配置文件中配置bean：

<bean id="mailSender" class="org.springframework.mail.javamail.JavaMailSenderImpl">
            <property name="host" value="smtp.mxhichina.com"/>
            <property name="username" value="输入发送邮箱地址"/>
            <property name="password" value="输入发送邮箱密码"/>
        </bean>
        <bean id="sendEmailService" class="cn.ssm.service.SendEmailService">
            <property name="sender" ref="mailSender"/>
            <property name="velocityEngine" ref="velocityEngine"/>
        </bean>
        <bean id="velocityEngine" class="org.springframework.ui.velocity.VelocityEngineFactoryBean">
            <property name="velocityProperties">
                <props>
                    <prop key="resource.loader">class</prop>
                    <prop key="class.resource.loader.class">
                        org.apache.velocity.runtime.resource.loader.ClasspathResourceLoader
                    </prop>
                    
                    <prop key="input.encoding">UTF-8</prop>
                    
                    <prop key="output.encoding">UTF-8</prop>
                    <prop key="default.contentType">application/x-www-form-urlencoded; charset=UTF-8</prop>
                </props>
            </property>
        </bean>

> 注意：需要将代码替换成自己的邮箱帐号和密码，否则发送失败

最后，写个测试用例：

@RunWith(SpringJUnit4ClassRunner.class)
    @ContextConfiguration(locations = "classpath:applicationContext.xml")
    public class SendEmailTest { 
    
        @Autowired
        private SendEmailService emailService;
    
        @Test
        public void test() {
            emailService.sendEmail();
        }
    }

运行后，效果如下：

![SouthEast][]

可以正确显示html格式并显示中文。

[SouthEast]: /images/20220711/1d51646684d7458d82267803c21f3ec6.png