@Component
@ConfigurationProperties(prefix="person")
publicclassPerson{
}
需要添加依赖才有提示
dependencies{
optional "org.springframework.boot:spring-boot-configuration-processor"
}
properties乱码问题
@Value和@ConfigurationProperties取值的不同
@ConfigurationProperties@Value
功能批量注入配置的属性值一个一个指定
松散语法(下划线转和字母大写变量名可识别)支持不支持
SpEL不支持支持
JSR303数据校验支持不支持
@PropertySource和@ImportSource
@PropertySource(value={"classpath:xxx.properties"}),加载另外的配置文件
@ImportResource(locations={"classpath:xxx.xml"}):导入Spring的配置文件,用在配置类上
xml文件替换成配置类
@Configuration
publicclassMyAppConfig{
//<bean></bean>将方法的返回值添加到容器中，容器中该组件的默认id就是方法名
@Bean
publicHelloServicehelloService(){
returnnewHelloService();
}
}
配置文件占位符
${random.uuid}
${user.name:默认值}
profiles标识
不同环境可以使用不同的配置文件
application.properties
spring.profiles.active=dev #激活dev环境的配置
application-dev.properties
springboot配置文件加载顺序
file:./config/
file:./
classpath:./config/
classpath:/
优先级由高到低，高的会覆盖低的
自动配置原理
1）、Springboot启动时加载主配置类，@SpringBootApplication中启用了自动配置@EnableAutoConfiguration
2）、在@EnableAutoConfiguration中用@Import(AutoConfigurationImportSelector.class)导入组件
3）、在AutoConfigurationImportSelector类中有一个selectImports方法
4）、在getAutoConfigurationEntry中调用getCandidateConfigurations从springfactory加载工厂
5）、loadFactoryNames中返回loadFactoryNames从FACTORIES_RESOURCE_LOCATION = "META-INF/spring.factories";读取EnableAutoConfiguration.class的内容包装成properties对象
根据不同的条件判断决定该配置类是否生效
@Configuration//这是一个配置类
@EnableConfigurationProperties(HttpProperties.class)//启用制定类的ConfigurationProperties功能
@ConditionalOnWebApplication(type=ConditionalOnWebApplication.Type.SERVLET)//spring底层@Conditional注解，根据不同的条件，如果满足条件该配置类生效
@ConditionalOnClass(CharacterEncodingFilter.class)//判断当前项目有没有这个类
@ConditionalOnProperty(prefix="spring.http.encoding",value="enabled",matchIfMissing=true)//判断配置文件是否存在这些配置，matchIfMissing如果不存在还是返回true
publicclassHttpEncodingAutoConfiguration{
privatefinalHttpProperties.Encodingproperties;
publicHttpEncodingAutoConfiguration(HttpPropertiesproperties) {
this.properties=properties.getEncoding();
}
@Bean//给容器中添加这个组件
@ConditionalOnMissingBean//判断容器中没有这个组件时
publicCharacterEncodingFiltercharacterEncodingFilter() {
CharacterEncodingFilterfilter=newOrderedCharacterEncodingFilter();
filter.setEncoding(this.properties.getCharset().name());
filter.setForceRequestEncoding(this.properties.shouldForce(Type.REQUEST));
filter.setForceResponseEncoding(this.properties.shouldForce(Type.RESPONSE));
returnfilter;
}
@Bean
publicLocaleCharsetMappingsCustomizerlocaleCharsetMappingsCustomizer() {
returnnewLocaleCharsetMappingsCustomizer(this.properties);
}
privatestaticclassLocaleCharsetMappingsCustomizerimplements
WebServerFactoryCustomizer<ConfigurableServletWebServerFactory>,Ordered{
privatefinalHttpProperties.Encodingproperties;
LocaleCharsetMappingsCustomizer(HttpProperties.Encodingproperties) {
this.properties=properties;
}
@Override
publicvoidcustomize(ConfigurableServletWebServerFactoryfactory) {
if(this.properties.getMapping()!=null) {
factory.setLocaleCharsetMappings(this.properties.getMapping());
}
}
@Override
publicintgetOrder() {
return0;
}
}
}
自定义错误信息继承DefaultErrorAttributes重写getErrorAttributes方法调用super.getErrorAttributes将自己的错误信息写入map返回将map放入request域取出异常处理器中的信息(Map<String,Object>)requestAttributes.getAttribute("ext",0);
嵌入式servlet
修改tomcat配置
注册servlet(localhost:8080/myServlet)
@Bean
publicServletRegistrationBeanmyServlet(){
ServletRegistrationBeanservletbean=newServletRegistrationBean(newMyServlet(),"/myServlet");
returnservletbean;
}
注册filter
@Bean
publicFilterRegistrationBeanmyFilter(){
FilterRegistrationBeanfilterbean=newFilterRegistrationBean();
filterbean.setFilter(newMyFilter());//注册过滤器
filterbean.setUrlPatterns(Array.asList("/hello","/myServlet"));//过滤url
returnfilterbean;
}
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