看官方文档学习springcloud搭建
很多java的朋友学习新知识时候去百度,看了之后一知半解,不知道怎么操作,不知道到底什么什么东西,那么作为java码农到底该怎么学习额
一 百度是对还是错呢?
百度是一个万能的工具,当然是对也是错的,对于一些小知识,是可以百度的,但是例如学习springcloud,那么最好是进入官方文档进行查看,可以清晰查看到当前版本信息
因为很多时候,在版本迭代时候出现问题,那么看官方文档就可以很清晰知道这个问题。
那么问题来了,英文不好,怎么处理?
不用太担心,可以使用翻译工具:
可能有时候不准,但是我们作为程序员的应该知道如何处理,将不懂的单词进行留意,再去看文档。
二 看文档搭建eureka注册中心:
首先进入springcloud官网,eureka是netlex公司开发的,所以进入找相关模块,当然也有阿里巴巴的,
再找模块
Service Discovery: Eureka Server
相信大家知道这个什么意思了,服务发现,eureka服务端
我们可以使用idea去创建项目,
主pom,进行依赖控制,当然也可以这样,将他们分开,进行单独项目进行配置,那么可以单独建立,一个就不能拿到公司的所有的项目
<?xml version="1.0" encoding="UTF-8"?> <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd"> <modelVersion>4.0.0</modelVersion> <packaging>pom</packaging> <modules> <module>springrurekaserver</module> </modules> <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>2.1.8.RELEASE</version> <relativePath/> <!-- lookup parent from repository --> </parent> <groupId>com.cxy</groupId> <artifactId>springcloudlearning</artifactId> <version>0.0.1-SNAPSHOT</version> <name>springcloudlearning</name> <description>Demo project for Spring Boot</description> <properties> <java.version>1.8</java.version> <spring-cloud.version>Greenwich.SR3</spring-cloud.version> </properties> <dependencies> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-test</artifactId> </dependency> </dependencies> <dependencyManagement> <dependencies> <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-dependencies</artifactId> <version>${spring-cloud.version}</version> <type>pom</type> <scope>import</scope> </dependency> </dependencies> </dependencyManagement> <build> <plugins> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> </plugin> </plugins> </build> <!--<repositories> <repository> <id>spring-milestones</id> <name>Spring Milestones</name> <url>https://repo.spring.io/milestone</url> </repository> </repositories>--> </project>
<!--<repositories> <repository> <id>spring-milestones</id> <name>Spring Milestones</name> <url>https://repo.spring.io/milestone</url> </repository> </repositories>-->
这个部分为什么注释呢,由于在选版本时候,idea自己给我选择了版本,所以带出来了,官网这个不安全的版本。
然后参照官方:
引入依赖,所以这里就引入依赖:
然后再创建application。yml
server: port: 8761 eureka: instance: hostname: localhost client: registerWithEureka: false fetchRegistry: false serviceUrl: defaultZone: http://127.0.0.1:8761/eureka/
然后再创建
package com.cxy; import org.springframework.boot.Banner; import org.springframework.boot.SpringApplication; import org.springframework.boot.SpringBootVersion; import org.springframework.boot.WebApplicationType; import org.springframework.boot.autoconfigure.SpringBootApplication; import org.springframework.boot.builder.SpringApplicationBuilder; import org.springframework.cloud.netflix.eureka.server.EnableEurekaServer; @SpringBootApplication @EnableEurekaServer public class EurekaApplication { public static void main(String[] args) { new SpringApplicationBuilder(EurekaApplication.class) // .web(WebApplicationType.SERVLET) .main(SpringBootVersion.class) .run(args); /* SpringApplicationBuilder springApplicationBuilder = new SpringApplicationBuilder(EnableEurekaServer.class); SpringApplicationBuilder web = springApplicationBuilder.web(webappl); web.run(args); */ SpringApplication.run(EurekaApplication.class,args); } }
可以看下官方:
其实在那个web方法地方的时候会报错,所以我们需要点进源码看下:
传入了一个webApplicationType
这个是什么东西呢:
/* * Copyright 2012-2019 the original author or authors. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * https://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package org.springframework.boot; import org.springframework.util.ClassUtils; /** * An enumeration of possible types of web application. * * @author Andy Wilkinson * @author Brian Clozel * @since 2.0.0 */ public enum WebApplicationType { /** * The application should not run as a web application and should not start an * embedded web server. */ NONE, /** * The application should run as a servlet-based web application and should start an * embedded servlet web server. */ SERVLET, /** * The application should run as a reactive web application and should start an * embedded reactive web server. */ REACTIVE; private static final String[] SERVLET_INDICATOR_CLASSES = { "javax.servlet.Servlet", "org.springframework.web.context.ConfigurableWebApplicationContext" }; private static final String WEBMVC_INDICATOR_CLASS = "org.springframework." + "web.servlet.DispatcherServlet"; private static final String WEBFLUX_INDICATOR_CLASS = "org." + "springframework.web.reactive.DispatcherHandler"; private static final String JERSEY_INDICATOR_CLASS = "org.glassfish.jersey.servlet.ServletContainer"; private static final String SERVLET_APPLICATION_CONTEXT_CLASS = "org.springframework.web.context.WebApplicationContext"; private static final String REACTIVE_APPLICATION_CONTEXT_CLASS = "org.springframework.boot.web.reactive.context.ReactiveWebApplicationContext"; static WebApplicationType deduceFromClasspath() { if (ClassUtils.isPresent(WEBFLUX_INDICATOR_CLASS, null) && !ClassUtils.isPresent(WEBMVC_INDICATOR_CLASS, null) && !ClassUtils.isPresent(JERSEY_INDICATOR_CLASS, null)) { return WebApplicationType.REACTIVE; } for (String className : SERVLET_INDICATOR_CLASSES) { if (!ClassUtils.isPresent(className, null)) { return WebApplicationType.NONE; } } return WebApplicationType.SERVLET; } static WebApplicationType deduceFromApplicationContext(Class<?> applicationContextClass) { if (isAssignable(SERVLET_APPLICATION_CONTEXT_CLASS, applicationContextClass)) { return WebApplicationType.SERVLET; } if (isAssignable(REACTIVE_APPLICATION_CONTEXT_CLASS, applicationContextClass)) { return WebApplicationType.REACTIVE; } return WebApplicationType.NONE; } private static boolean isAssignable(String target, Class<?> type) { try { return ClassUtils.resolveClassName(target, null).isAssignableFrom(type); } catch (Throwable ex) { return false; } } }
枚举类,所以看下注释:
找到了第二种,可以看下,所以传入这个类型,
当然也可以采用其他方式进行:
例如:
官方启动会构建很多东西,可以加载spring的版本,还有配置,这些: