# 20.1. 默认属性

Spring Boot支持的一些库使用缓存提高性能，比如模板引擎将缓存编译完的模板以避免重复解析模板文件。另外，当服务静态资源时，Spring MVC能够加入HTTP缓存头来进行回应。 虽然缓存在产品中很有用，但开发期间就是个累赘了，因为缓存会阻碍你看到在应用中刚刚做出的修改。正是因为这个原因，`spring-boot-devtools`默认禁用那些缓存选项。 缓存选项通常配置在`application.properties`文件中，比如Thymeleaf提供了`spring.thymeleaf.cache`属性，`spring-boot-devtools`模块会自动应用敏感的`development-time`配置，而不是手动设置这些属性。

**注** 查看[DevToolsPropertyDefaultsPostProcessor](https://github.com/spring-projects/spring-boot/tree/master/spring-boot-devtools/src/main/java/org/springframework/boot/devtools/env/DevToolsPropertyDefaultsPostProcessor.java)获取完整的被应用的属性列表。


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