Freemarker和Thymeleaf混用，springboot只装配了其中一个bean问题的解决

application.properties中，我只对 thymeleaf进行了配置 因为我发现freemarker的配置并没有被获取到。

---

spring.thymeleaf.encoding=UTF-8

spring.thymeleaf.cache=false

spring.thymeleaf.mode=HTML5

spring.thymeleaf.prefix=classpath:/templates/

spring.thymeleaf.checkTemplateLocation=false

spring.thymeleaf.suffix=.html 

 

---

接着创建一个配置类 MvcConfig 继承 WebMvcConfigurerAdapter：

 

 

import org.springframework.boot.autoconfigure.EnableAutoConfiguration;

import org.springframework.context.annotation.Bean;

import org.springframework.context.annotation.Configuration;

import org.springframework.web.servlet.config.annotation.WebMvcConfigurerAdapter;

import org.springframework.web.servlet.view.freemarker.FreeMarkerViewResolver;

@Configuration

@EnableAutoConfiguration

public class MvcConfig extends WebMvcConfigurerAdapter {

@Bean

public FreeMarkerViewResolver freeMarkerViewResolver() {

MyFreeMarkerViewResolver resolver = new MyFreeMarkerViewResolver();

resolver.setPrefix(null);

resolver.setSuffix(".ftl");

resolver.setContentType("text/html; charset=UTF-8");

resolver.setRequestContextAttribute("request");

resolver.setExposeContextBeansAsAttributes(true);

resolver.setExposeRequestAttributes(true);

resolver.setExposeSessionAttributes(true);

resolver.setOrder(1);

return resolver;

}

}

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其中用到了一个MyFreeMarkerViewResolver，这个类继承了FreeMarkerViewResolver 并重写了其中的loadView 方法，这个方法去freemarker的模板路径下找对应的ftl文件如果没找到对应文件则返回null(原因后面说)，代码如下：

 

 

import java.io.IOException;

import java.util.Locale;

import org.springframework.web.servlet.view.freemarker.FreeMarkerViewResolver;

public class MyFreeMarkerViewResolver extends FreeMarkerViewResolver {

        // 由于我的freemarker 配置无法被加载所以我才写死的正确方法是 利用@Value注解获取

private String prefix = "classpath:/templates/“;

private String suffix = ".ftl";

@Override

protected org.springframework.web.servlet.View loadView(final String viewName, final Locale locale)

throws Exception {

String resourceName = prefix + viewName + suffix;

try {

this.getApplicationContext().getResource(resourceName).getInputStream();

} catch (final IOException e) {

if (logger.isDebugEnabled()) {

if (logger.isTraceEnabled()) {

logger.trace("视图名：" + resourceName + "不存在！");

} else {

logger.debug("视图名：" + resourceName + "不存在！");

}

}

return null;

}

return super.loadView(viewName, locale);

}

}

---

 

到这里就基本解决了SpringBoot只加载一个模板引擎的问题，下面说一说为什么要重写 FreeMarkerViewResolver 的 loadView()方法

在前端控制器DispatcherServlet中的viewResolvers保存的都是ViewResolver的实现类的对象,有一个resolveViewName() 方法会 遍历 viewResolvers,如果遇到 null则寻找下一个viewResolver，如果viewResolver！=null则使用它：

 

1. protected View resolveViewName(String viewName, Map<String, Object> model, Locale locale,  

2.         HttpServletRequest request) throws Exception {  

3.   

4.     for (ViewResolver viewResolver : this.viewResolvers) {  

5.         View view = viewResolver.resolveViewName(viewName, locale);  

6.         if (view != null) {  

7.             return view;  

8.         }  

9.     }  

10.     return null;  

11. }  

 

如果在完成以上配置后成功装配两个模板引擎但是遇到静态 文件加载失败的问题请参考我的另一片博客：https://blog.youkuaiyun.com/weixin_42851893/article/details/87977523