optimize EMailUtils

Author: litongjava

docs/zh/22_tio-utils/04.md

@@ -4,7 +4,7 @@ tio-utils 内置了邮箱工具类 com.litongjava.tio.utils.email.EMailUtils 用
 
 ## 添加依赖
 
-```
+```xml
 <dependency>
   <groupId>javax.mail</groupId>
   <artifactId>mail</artifactId>
@@ -29,7 +29,7 @@ mail.from=litongjava_alarm
 
 测试发送
 
-```
+```java
 String filename = "app.properties";
 EnvironmentUtils.load(filename);
 EMailUtils.send("[email protected]", "验证码", "欢迎你登录XXX系统,你的验证码是 1234");
@@ -52,8 +52,8 @@ mail.from=smtp_alarm
 ```
 
 ```java
-package com.litongjava.tio.utils.email;
-
+import com.litongjava.tio.utils.email.EMailUtils;
+import com.litongjava.tio.utils.email.GMailFactory;
 import com.litongjava.tio.utils.environment.EnvironmentUtils;
 
 public class GmailTest {
@@ -62,8 +62,8 @@ public class GmailTest {
     EMailUtils.setEMailFactory(new GMailFactory());
     EMailUtils.send("[email protected]", "Adsgency AI Email Verification", "Your email verification code is 164403");
   }
-
 }
+
 ```
 
 ### 获取 Gmail 授权码
@@ -165,7 +165,7 @@ public class GmailTest {
 - 2.实现类 com.litongjava.tio.utils.email.IEMailFactory 重写 getMail 方法 返回 Mail
 - 3. 调用 com.litongjava.tio.utils.email.EMailUtils.setEMailFactory(IEMailFactory) 设置实现类
 
-```
+```java
 package com.litongjava.tio.utils.email;
 
 import java.util.Properties;
@@ -203,7 +203,7 @@ public class Wangyi126Mail implements EMail {
 
 ```
 
-```
+```java
 package com.litongjava.tio.utils.email;
 
 public class Wangyi126MailFactory implements IEMailFactory {