spring-boot4

Posted 2020-10-29 672530440

1.1.1. Starter pom

除了官方也有其他第三方提供的starter

Websocket是服务端推数据到客户端。长连接。
1.1.1.Xml 配置文件
有些时候必须使用xml配置。

1.1.1.日志
Spring Boot对各种日志框架都做了支持，我们可以通过配置来修改默认的日志的配置：

#设置日志级别
logging.level.org.springframework=DEBUG

格式：
logging.level.*= # Log levels severity mapping. For instance `logging.level.org.springframework=DEBUG`
1.2.Spring Boot的自动配置的原理
Spring Boot在进行SpringApplication对象实例化时会加载META-INF/spring.factories文件，将该配置文件中的配置载入到Spring容器。Spring-boot1.4.5.RELEASE.jar\\META-INF\\spring.factores。在spring.factores这个配置文件中配置了一系列的内容，通过代码读取这个配置文件中的内容，然后做一系列的实例化，然后只要加入某些功能就会自动完成配置。
1.2.1.Maven下载源码
通过 dependency:sources 该命令可以下载该项目中所有的依赖的包的源码。
1.2.2.源码分析
org.springframework.boot.SpringApplication：

org.springframework.core.io.support.SpringFactoriesLoader:

由此可见，读取该配置文件来加载内容。
1.1.1.Spring.factories文件
# Initializers
org.springframework.context.ApplicationContextInitializer=\\
org.springframework.boot.autoconfigure.SharedMetadataReaderFactoryContextInitializer,\\
org.springframework.boot.autoconfigure.logging.AutoConfigurationReportLoggingInitializer

# Application Listeners
org.springframework.context.ApplicationListener=\\
org.springframework.boot.autoconfigure.BackgroundPreinitializer

# Auto Configuration Import Listeners
org.springframework.boot.autoconfigure.AutoConfigurationImportListener=\\
org.springframework.boot.autoconfigure.condition.ConditionEvaluationReportAutoConfigurationImportListener

# Auto Configuration Import Filters
org.springframework.boot.autoconfigure.AutoConfigurationImportFilter=\\
org.springframework.boot.autoconfigure.condition.OnClassCondition

# Auto Configure
org.springframework.boot.autoconfigure.EnableAutoConfiguration=\\
org.springframework.boot.autoconfigure.admin.SpringApplicationAdminJmxAutoConfiguration,\\
org.springframework.boot.autoconfigure.aop.AopAutoConfiguration,\\
org.springframework.boot.autoconfigure.amqp.RabbitAutoConfiguration,\\
org.springframework.boot.autoconfigure.batch.BatchAutoConfiguration,\\
org.springframework.boot.autoconfigure.cache.CacheAutoConfiguration,\\
org.springframework.boot.autoconfigure.cassandra.CassandraAutoConfiguration,\\
org.springframework.boot.autoconfigure.cloud.CloudAutoConfiguration,\\
org.springframework.boot.autoconfigure.context.ConfigurationPropertiesAutoConfiguration,\\
org.springframework.boot.autoconfigure.context.MessageSourceAutoConfiguration,\\
org.springframework.boot.autoconfigure.context.PropertyPlaceholderAutoConfiguration,\\
org.springframework.boot.autoconfigure.couchbase.CouchbaseAutoConfiguration,\\
org.springframework.boot.autoconfigure.dao.PersistenceExceptionTranslationAutoConfiguration,\\
org.springframework.boot.autoconfigure.data.cassandra.CassandraDataAutoConfiguration,\\
org.springframework.boot.autoconfigure.data.cassandra.CassandraRepositoriesAutoConfiguration,\\
org.springframework.boot.autoconfigure.data.couchbase.CouchbaseDataAutoConfiguration,\\
org.springframework.boot.autoconfigure.data.couchbase.CouchbaseRepositoriesAutoConfiguration,\\
org.springframework.boot.autoconfigure.data.elasticsearch.ElasticsearchAutoConfiguration,\\
org.springframework.boot.autoconfigure.data.elasticsearch.ElasticsearchDataAutoConfiguration,\\
org.springframework.boot.autoconfigure.data.elasticsearch.ElasticsearchRepositoriesAutoConfiguration,\\
org.springframework.boot.autoconfigure.data.jpa.JpaRepositoriesAutoConfiguration,\\
org.springframework.boot.autoconfigure.data.ldap.LdapDataAutoConfiguration,\\
org.springframework.boot.autoconfigure.data.ldap.LdapRepositoriesAutoConfiguration,\\
org.springframework.boot.autoconfigure.data.mongo.MongoDataAutoConfiguration,\\
org.springframework.boot.autoconfigure.data.mongo.MongoRepositoriesAutoConfiguration,\\
org.springframework.boot.autoconfigure.data.neo4j.Neo4jDataAutoConfiguration,\\
org.springframework.boot.autoconfigure.data.neo4j.Neo4jRepositoriesAutoConfiguration,\\
org.springframework.boot.autoconfigure.data.solr.SolrRepositoriesAutoConfiguration,\\
org.springframework.boot.autoconfigure.data.redis.RedisAutoConfiguration,\\
org.springframework.boot.autoconfigure.data.redis.RedisRepositoriesAutoConfiguration,\\
org.springframework.boot.autoconfigure.data.rest.RepositoryRestMvcAutoConfiguration,\\
org.springframework.boot.autoconfigure.data.web.SpringDataWebAutoConfiguration,\\
org.springframework.boot.autoconfigure.elasticsearch.jest.JestAutoConfiguration,\\
org.springframework.boot.autoconfigure.freemarker.FreeMarkerAutoConfiguration,\\
org.springframework.boot.autoconfigure.gson.GsonAutoConfiguration,\\
org.springframework.boot.autoconfigure.h2.H2ConsoleAutoConfiguration,\\
org.springframework.boot.autoconfigure.hateoas.HypermediaAutoConfiguration,\\
org.springframework.boot.autoconfigure.hazelcast.HazelcastAutoConfiguration,\\
org.springframework.boot.autoconfigure.hazelcast.HazelcastJpaDependencyAutoConfiguration,\\
org.springframework.boot.autoconfigure.info.ProjectInfoAutoConfiguration,\\
org.springframework.boot.autoconfigure.integration.IntegrationAutoConfiguration,\\
org.springframework.boot.autoconfigure.jackson.JacksonAutoConfiguration,\\
org.springframework.boot.autoconfigure.jdbc.DataSourceAutoConfiguration,\\
org.springframework.boot.autoconfigure.jdbc.JdbcTemplateAutoConfiguration,\\
org.springframework.boot.autoconfigure.jdbc.JndiDataSourceAutoConfiguration,\\
org.springframework.boot.autoconfigure.jdbc.XADataSourceAutoConfiguration,\\
org.springframework.boot.autoconfigure.jdbc.DataSourceTransactionManagerAutoConfiguration,\\
org.springframework.boot.autoconfigure.jms.JmsAutoConfiguration,\\
org.springframework.boot.autoconfigure.jmx.JmxAutoConfiguration,\\
org.springframework.boot.autoconfigure.jms.JndiConnectionFactoryAutoConfiguration,\\
org.springframework.boot.autoconfigure.jms.activemq.ActiveMQAutoConfiguration,\\
org.springframework.boot.autoconfigure.jms.artemis.ArtemisAutoConfiguration,\\
org.springframework.boot.autoconfigure.flyway.FlywayAutoConfiguration,\\
org.springframework.boot.autoconfigure.groovy.template.GroovyTemplateAutoConfiguration,\\
org.springframework.boot.autoconfigure.jersey.JerseyAutoConfiguration,\\
org.springframework.boot.autoconfigure.jooq.JooqAutoConfiguration,\\
org.springframework.boot.autoconfigure.kafka.KafkaAutoConfiguration,\\
org.springframework.boot.autoconfigure.ldap.embedded.EmbeddedLdapAutoConfiguration,\\
org.springframework.boot.autoconfigure.ldap.LdapAutoConfiguration,\\
org.springframework.boot.autoconfigure.liquibase.LiquibaseAutoConfiguration,\\
org.springframework.boot.autoconfigure.mail.MailSenderAutoConfiguration,\\
org.springframework.boot.autoconfigure.mail.MailSenderValidatorAutoConfiguration,\\
org.springframework.boot.autoconfigure.mobile.DeviceResolverAutoConfiguration,\\
org.springframework.boot.autoconfigure.mobile.DeviceDelegatingViewResolverAutoConfiguration,\\
org.springframework.boot.autoconfigure.mobile.SitePreferenceAutoConfiguration,\\
org.springframework.boot.autoconfigure.mongo.embedded.EmbeddedMongoAutoConfiguration,\\
org.springframework.boot.autoconfigure.mongo.MongoAutoConfiguration,\\
org.springframework.boot.autoconfigure.mustache.MustacheAutoConfiguration,\\
org.springframework.boot.autoconfigure.orm.jpa.HibernateJpaAutoConfiguration,\\
org.springframework.boot.autoconfigure.reactor.ReactorAutoConfiguration,\\
org.springframework.boot.autoconfigure.security.SecurityAutoConfiguration,\\
org.springframework.boot.autoconfigure.security.SecurityFilterAutoConfiguration,\\
org.springframework.boot.autoconfigure.security.FallbackWebSecurityAutoConfiguration,\\
org.springframework.boot.autoconfigure.security.oauth2.OAuth2AutoConfiguration,\\
org.springframework.boot.autoconfigure.sendgrid.SendGridAutoConfiguration,\\
org.springframework.boot.autoconfigure.session.SessionAutoConfiguration,\\
org.springframework.boot.autoconfigure.social.SocialWebAutoConfiguration,\\
org.springframework.boot.autoconfigure.social.FacebookAutoConfiguration,\\
org.springframework.boot.autoconfigure.social.LinkedInAutoConfiguration,\\
org.springframework.boot.autoconfigure.social.TwitterAutoConfiguration,\\
org.springframework.boot.autoconfigure.solr.SolrAutoConfiguration,\\
org.springframework.boot.autoconfigure.thymeleaf.ThymeleafAutoConfiguration,\\
org.springframework.boot.autoconfigure.transaction.TransactionAutoConfiguration,\\
org.springframework.boot.autoconfigure.transaction.jta.JtaAutoConfiguration,\\
org.springframework.boot.autoconfigure.validation.ValidationAutoConfiguration,\\
org.springframework.boot.autoconfigure.web.DispatcherServletAutoConfiguration,\\
org.springframework.boot.autoconfigure.web.EmbeddedServletContainerAutoConfiguration,\\
org.springframework.boot.autoconfigure.web.ErrorMvcAutoConfiguration,\\
org.springframework.boot.autoconfigure.web.HttpEncodingAutoConfiguration,\\
org.springframework.boot.autoconfigure.web.HttpMessageConvertersAutoConfiguration,\\
org.springframework.boot.autoconfigure.web.MultipartAutoConfiguration,\\
org.springframework.boot.autoconfigure.web.ServerPropertiesAutoConfiguration,\\
org.springframework.boot.autoconfigure.web.WebClientAutoConfiguration,\\
org.springframework.boot.autoconfigure.web.WebMvcAutoConfiguration,\\
org.springframework.boot.autoconfigure.websocket.WebSocketAutoConfiguration,\\
org.springframework.boot.autoconfigure.websocket.WebSocketMessagingAutoConfiguration,\\
org.springframework.boot.autoconfigure.webservices.WebServicesAutoConfiguration

# Failure analyzers
org.springframework.boot.diagnostics.FailureAnalyzer=\\
org.springframework.boot.autoconfigure.diagnostics.analyzer.NoSuchBeanDefinitionFailureAnalyzer,\\
org.springframework.boot.autoconfigure.jdbc.DataSourceBeanCreationFailureAnalyzer,\\
org.springframework.boot.autoconfigure.jdbc.HikariDriverConfigurationFailureAnalyzer

# Template availability providers
org.springframework.boot.autoconfigure.template.TemplateAvailabilityProvider=\\
org.springframework.boot.autoconfigure.freemarker.FreeMarkerTemplateAvailabilityProvider,\\
org.springframework.boot.autoconfigure.mustache.MustacheTemplateAvailabilityProvider,\\
org.springframework.boot.autoconfigure.groovy.template.GroovyTemplateAvailabilityProvider,\\
org.springframework.boot.autoconfigure.thymeleaf.ThymeleafTemplateAvailabilityProvider,\\
org.springframework.boot.autoconfigure.web.JspTemplateAvailabilityProvider

1.1.1.举例：Redis的自动配置
从上述的配置中可以看出，org.springframework.boot.autoconfigure.data.redis.RedisAutoConfiguration是Redis的自动配置。

内容：

1.1.1. 条件注解

1. Spring Boot的web开发

Web开发的自动配置类：org.springframework.boot.autoconfigure.web.WebMvcAutoConfiguration

1.1. 自动配置的ViewResolver

视图的配置mvcProperties对象中：

org.springframework.boot.autoconfigure.web.WebMvcProperties.View

1.1. 自动配置静态资源

1.1.1. 进入规则为 /

如果进入SpringMVC的规则为/时，Spring Boot的默认静态资源的路径为：

spring.resources.static-locations=classpath:/META-INF/resources/,classpath:/resources/,classpath:/static/,classpath:/public/

 

测试：

1.1.1. 进入规则为*.xxx 或者 不指定静态文件路径时

将静态资源放置到webapp下的static目录中即可通过地址访问：

测试：

1.1.自定义消息转化器
自定义消息转化器，只需要在@Configuration的类中添加消息转化器的@bean加入到Spring容器，就会被Spring Boot自动加入到容器中。

    @Bean
    public StringHttpMessageConverter stringHttpMessageConverter(){
        StringHttpMessageConverter converter  = new StringHttpMessageConverter(Charset.forName("UTF-8"));
        return converter;
}


默认配置：

1.1.自定义SpringMVC的配置
有些时候我们需要自已配置SpringMVC而不是采用默认，比如说增加一个拦截器，这个时候就得通过继承WebMvcConfigurerAdapter然后重写父类中的方法进行扩展。

import java.nio.charset.Charset;
import java.util.List;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.springframework.context.annotation.Configuration;
import org.springframework.http.converter.HttpMessageConverter;
import org.springframework.http.converter.StringHttpMessageConverter;
import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;
import org.springframework.web.servlet.config.annotation.InterceptorRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurerAdapter;
//这个类跟HelloApplication是同级目录，会扫描到，生效。
@Configuration  //申明这是一个配置，加入到spring的容器。
public class MySrpingMVCConfig extends WebMvcConfigurerAdapter{

    // 自定义拦截器，所有请求都拦截
    @Override
    public void addInterceptors(InterceptorRegistry registry) {
        HandlerInterceptor handlerInterceptor = new HandlerInterceptor() {
            @Override
            public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler)
                    throws Exception {
                System.out.println("自定义拦截器............");
                return true;
            }
            
            @Override
            public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler,
                    ModelAndView modelAndView) throws Exception {
                
            }
            
            @Override
            public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler,
                    Exception ex) throws Exception {
            }
        };
        registry.addInterceptor(handlerInterceptor).addPathPatterns("/**");
    }

    // 自定义消息转化器的第二种方法
    @Override
    public void configureMessageConverters(List<HttpMessageConverter<?>> converters) {
        StringHttpMessageConverter converter  = new StringHttpMessageConverter(Charset.forName("UTF-8"));
        converters.add(converter);
    }

}