第一个Spring Boot Web程序

需要的环境和工具：

1、Eclipse
2、Java环境（JDK 1.7或以上版本）
3、Maven 3.0+（Eclipse已经内置了）

写个Hello Spring:

1、新建一个Maven项目，项目名称为 SpringTest

 选择 maven-archetype-quickstart 

删除项目中的 test，这个我们用不到， 刚刚建好的项目如图所示：

修改 pom.xml ，如果你是第一次玩Spring那么修改pom.xml后Eclipse会自动下载相关依赖包:

<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 http://maven.apache.org/xsd/maven-4.0.0.xsd">
  <modelVersion>4.0.0</modelVersion>

  <groupId>test.com</groupId>
  <artifactId>SpringTest</artifactId>
  <version>0.0.1-SNAPSHOT</version>
  <packaging>jar</packaging>

  <name>SpringTest</name>
  <url>http://maven.apache.org</url>

  <properties>
    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    <java.version>1.8</java.version>
  </properties>
  
  <parent>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-parent</artifactId>
    <version>1.2.5.RELEASE</version>
    <relativePath/>
  </parent>

  <dependencies>
    <dependency>
      <groupId>org.springframework.boot</groupId>
      <artifactId>spring-boot-starter-web</artifactId>
    </dependency>
  </dependencies>

  <build>
    <plugins>
      <plugin>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-maven-plugin</artifactId>
      </plugin>
    </plugins>
  </build>
  
</project>

再修改 test.com.SpringTest 里面的 App.java

package test.com.SpringTest;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
import org.springframework.boot.context.embedded.EmbeddedServletContainerFactory;
import org.springframework.boot.context.embedded.tomcat.TomcatEmbeddedServletContainerFactory;
import org.springframework.context.annotation.Bean;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

@RestController
@EnableAutoConfiguration
public class App 
{
    @RequestMapping("/m")
    public String springtest() {
        return "Hello spring!";
    }
    
    @RequestMapping("/")
    public String index() {
        return "Hello World!";
    }
    
    public static void main( String[] args )
    {
        System.out.println( "App start!" );
        SpringApplication.run(App.class, args);
    }

}

两个文件修改好了直接Run As - Java Application

控制台看到下面这样的内容就说明运行成功了！ 

打开浏览器，访问 http://localhost:8080  或者访问 http://localhost:8080/m 就能看到成果了！是不是很简单的。

    

学习总结

1、修改XML文件是为了增加springframework的依赖包

2、Spring应用上下文：　　

　　我们在App的main入口调用了 SpringApplication.run(App.class, args);  SpringApplication是Spring Boot框架中描述Spring应用的类，它的run()方法会创建一个Spring应用上下文（Application Context）。

3、路由的设置：

　　@RequestMapping注解表明该方法处理那些URL对应的HTTP请求，也就是我们常说的URL路由。在这个例子中我们定义了两个路由 “/” 和 “/m”

　　http://localhost:8080/　  　 被路由至 index()方法进行处理

　　http://localhost:8080/m　　被路由至springtest()方法进行处理

　　如果我们需要将访问的地址修改成：http://localhost:8080/Api/    http://localhost:8080/Api/m 来访问这两个方法，可以在class App上面加一个RequestMapping注释：

　　

　　

4、端口的修改

　　如果要修改默认的8080端口可以在项目根目录新建一个 application.properties 文件，文件内容为：

server.port=8081  

　　重新Run一下，端口就修改成了8081，

　　配置文件的详情可以看下面的附录：

# ===================================================================
# COMMON SPRING BOOT PROPERTIES
#
# This sample file is provided as a guideline. Do NOT copy it in its
# entirety to your own application.               ^^^
# ===================================================================

# ----------------------------------------
# CORE PROPERTIES
# ----------------------------------------

# SPRING CONFIG (ConfigFileApplicationListener)
spring.config.name= # config file name (default to 'application')
spring.config.location= # location of config file

# PROFILES
spring.profiles= # comma list of active profiles

# APPLICATION SETTINGS (SpringApplication)
spring.main.sources=
spring.main.web-environment= # detect by default
spring.main.show-banner=true
spring.main....= # see class for all properties

# LOGGING
logging.path=/var/logs
logging.file=myapp.log
logging.config=

# IDENTITY (ContextIdApplicationContextInitializer)
spring.application.name=
spring.application.index=

# EMBEDDED SERVER CONFIGURATION (ServerProperties)
server.port=8080
server.address= # bind to a specific NIC
server.session-timeout= # session timeout in seconds
server.context-path= # the context path, defaults to '/'
server.servlet-path= # the servlet path, defaults to '/'
server.tomcat.access-log-pattern= # log pattern of the access log
server.tomcat.access-log-enabled=false # is access logging enabled
server.tomcat.protocol-header=x-forwarded-proto # ssl forward headers
server.tomcat.remote-ip-header=x-forwarded-for
server.tomcat.basedir=/tmp # base dir (usually not needed, defaults to tmp)
server.tomcat.background-processor-delay=30; # in seconds
server.tomcat.max-threads = 0 # number of threads in protocol handler
server.tomcat.uri-encoding = UTF-8 # character encoding to use for URL decoding

# SPRING MVC (HttpMapperProperties)
http.mappers.json-pretty-print=false # pretty print JSON
http.mappers.json-sort-keys=false # sort keys
spring.mvc.locale= # set fixed locale, e.g. en_UK
spring.mvc.date-format= # set fixed date format, e.g. dd/MM/yyyy
spring.mvc.message-codes-resolver-format= # PREFIX_ERROR_CODE / POSTFIX_ERROR_CODE
spring.view.prefix= # MVC view prefix
spring.view.suffix= # ... and suffix
spring.resources.cache-period= # cache timeouts in headers sent to browser
spring.resources.add-mappings=true # if default mappings should be added

# THYMELEAF (ThymeleafAutoConfiguration)
spring.thymeleaf.prefix=classpath:/templates/
spring.thymeleaf.suffix=.html
spring.thymeleaf.mode=HTML5
spring.thymeleaf.encoding=UTF-8
spring.thymeleaf.content-type=text/html # ;charset=<encoding> is added
spring.thymeleaf.cache=true # set to false for hot refresh

# FREEMARKER (FreeMarkerAutoConfiguration)
spring.freemarker.allowRequestOverride=false
spring.freemarker.allowSessionOverride=false
spring.freemarker.cache=true
spring.freemarker.checkTemplateLocation=true
spring.freemarker.contentType=text/html
spring.freemarker.exposeRequestAttributes=false
spring.freemarker.exposeSessionAttributes=false
spring.freemarker.exposeSpringMacroHelpers=false
spring.freemarker.prefix=
spring.freemarker.requestContextAttribute=
spring.freemarker.settings.*=
spring.freemarker.suffix=.ftl
spring.freemarker.templateEncoding=UTF-8
spring.freemarker.templateLoaderPath=classpath:/templates/
spring.freemarker.viewNames= # whitelist of view names that can be resolved

# GROOVY TEMPLATES (GroovyTemplateAutoConfiguration)
spring.groovy.template.allowRequestOverride=false
spring.groovy.template.allowSessionOverride=false
spring.groovy.template.cache=true
spring.groovy.template.configuration.*= # See Groovy's TemplateConfiguration
spring.groovy.template.contentType=text/html
spring.groovy.template.prefix=classpath:/templates/
spring.groovy.template.suffix=.tpl
spring.groovy.template.templateEncoding=UTF-8
spring.groovy.template.viewNames= # whitelist of view names that can be resolved

# VELOCITY TEMPLATES (VelocityAutoConfiguration)
spring.velocity.allowRequestOverride=false
spring.velocity.allowSessionOverride=false
spring.velocity.cache=true
spring.velocity.checkTemplateLocation=true
spring.velocity.contentType=text/html
spring.velocity.dateToolAttribute=
spring.velocity.exposeRequestAttributes=false
spring.velocity.exposeSessionAttributes=false
spring.velocity.exposeSpringMacroHelpers=false
spring.velocity.numberToolAttribute=
spring.velocity.prefix=
spring.velocity.properties.*=
spring.velocity.requestContextAttribute=
spring.velocity.resourceLoaderPath=classpath:/templates/
spring.velocity.suffix=.vm
spring.velocity.templateEncoding=UTF-8
spring.velocity.viewNames= # whitelist of view names that can be resolved

# INTERNATIONALIZATION (MessageSourceAutoConfiguration)
spring.messages.basename=messages
spring.messages.cacheSeconds=-1
spring.messages.encoding=UTF-8


# SECURITY (SecurityProperties)
security.user.name=user # login username
security.user.password= # login password
security.user.role=USER # role assigned to the user
security.require-ssl=false # advanced settings ...
security.enable-csrf=false
security.basic.enabled=true
security.basic.realm=Spring
security.basic.path= # /**
security.headers.xss=false
security.headers.cache=false
security.headers.frame=false
security.headers.contentType=false
security.headers.hsts=all # none / domain / all
security.sessions=stateless # always / never / if_required / stateless
security.ignored=false

# DATASOURCE (DataSourceAutoConfiguration & DataSourceProperties)
spring.datasource.name= # name of the data source
spring.datasource.initialize=true # populate using data.sql
spring.datasource.schema= # a schema (DDL) script resource reference
spring.datasource.data= # a data (DML) script resource reference
spring.datasource.platform= # the platform to use in the schema resource (schema-${platform}.sql)
spring.datasource.continueOnError=false # continue even if can't be initialized
spring.datasource.separator=; # statement separator in SQL initialization scripts
spring.datasource.driverClassName= # JDBC Settings...
spring.datasource.url=
spring.datasource.username=
spring.datasource.password=
spring.datasource.max-active=100 # Advanced configuration...
spring.datasource.max-idle=8
spring.datasource.min-idle=8
spring.datasource.initial-size=10
spring.datasource.validation-query=
spring.datasource.test-on-borrow=false
spring.datasource.test-on-return=false
spring.datasource.test-while-idle=
spring.datasource.time-between-eviction-runs-millis=
spring.datasource.min-evictable-idle-time-millis=
spring.datasource.max-wait-millis=

# MONGODB (MongoProperties)
spring.data.mongodb.host= # the db host
spring.data.mongodb.port=27017 # the connection port (defaults to 27107)
spring.data.mongodb.uri=mongodb://localhost/test # connection URL
spring.data.mongo.repositories.enabled=true # if spring data repository support is enabled

# JPA (JpaBaseConfiguration, HibernateJpaAutoConfiguration)
spring.jpa.properties.*= # properties to set on the JPA connection
spring.jpa.openInView=true
spring.jpa.show-sql=true
spring.jpa.database-platform=
spring.jpa.database=
spring.jpa.generate-ddl=false # ignored by Hibernate, might be useful for other vendors
spring.jpa.hibernate.naming-strategy= # naming classname
spring.jpa.hibernate.ddl-auto= # defaults to create-drop for embedded dbs
spring.data.jpa.repositories.enabled=true # if spring data repository support is enabled

# SOLR (SolrProperties})
spring.data.solr.host=http://127.0.0.1:8983/solr
spring.data.solr.zkHost=
spring.data.solr.repositories.enabled=true # if spring data repository support is enabled

# ELASTICSEARCH (ElasticsearchProperties})
spring.data.elasticsearch.cluster-name= # The cluster name (defaults to elasticsearch)
spring.data.elasticsearch.cluster-nodes= # The address(es) of the server node (comma-separated; if not specified starts a client node)
spring.data.elasticsearch.local=true # if local mode should be used with client nodes
spring.data.elasticsearch.repositories.enabled=true # if spring data repository support is enabled



# FLYWAY (FlywayProperties)
flyway.locations=classpath:db/migrations # locations of migrations scripts
flyway.schemas= # schemas to update
flyway.initVersion= 1 # version to start migration
flyway.prefix=V
flyway.suffix=.sql
flyway.enabled=true
flyway.url= # JDBC url if you want Flyway to create its own DataSource
flyway.user= # JDBC username if you want Flyway to create its own DataSource
flyway.password= # JDBC password if you want Flyway to create its own DataSource

# LIQUIBASE (LiquibaseProperties)
liquibase.change-log=classpath:/db/changelog/db.changelog-master.yaml
liquibase.contexts= # runtime contexts to use
liquibase.default-schema= # default database schema to use
liquibase.drop-first=false
liquibase.enabled=true

# JMX
spring.jmx.enabled=true # Expose MBeans from Spring

# RABBIT (RabbitProperties)
spring.rabbitmq.host= # connection host
spring.rabbitmq.port= # connection port
spring.rabbitmq.addresses= # connection addresses (e.g. myhost:9999,otherhost:1111)
spring.rabbitmq.username= # login user
spring.rabbitmq.password= # login password
spring.rabbitmq.virtualhost=
spring.rabbitmq.dynamic=

# REDIS (RedisProperties)
spring.redis.host=localhost # server host
spring.redis.password= # server password
spring.redis.port=6379 # connection port
spring.redis.pool.max-idle=8 # pool settings ...
spring.redis.pool.min-idle=0
spring.redis.pool.max-active=8
spring.redis.pool.max-wait=-1

# ACTIVEMQ (ActiveMQProperties)
spring.activemq.broker-url=tcp://localhost:61616 # connection URL
spring.activemq.user=
spring.activemq.password=
spring.activemq.in-memory=true # broker kind to create if no broker-url is specified
spring.activemq.pooled=false

# HornetQ (HornetQProperties)
spring.hornetq.mode= # connection mode (native, embedded)
spring.hornetq.host=localhost # hornetQ host (native mode)
spring.hornetq.port=5445 # hornetQ port (native mode)
spring.hornetq.embedded.enabled=true # if the embedded server is enabled (needs hornetq-jms-server.jar)
spring.hornetq.embedded.serverId= # auto-generated id of the embedded server (integer)
spring.hornetq.embedded.persistent=false # message persistence
spring.hornetq.embedded.data-directory= # location of data content (when persistence is enabled)
spring.hornetq.embedded.queues= # comma separate queues to create on startup
spring.hornetq.embedded.topics= # comma separate topics to create on startup
spring.hornetq.embedded.cluster-password= # customer password (randomly generated by default)

# JMS (JmsProperties)
spring.jms.pub-sub-domain= # false for queue (default), true for topic

# SPRING BATCH (BatchDatabaseInitializer)
spring.batch.job.names=job1,job2
spring.batch.job.enabled=true
spring.batch.initializer.enabled=true
spring.batch.schema= # batch schema to load

# AOP
spring.aop.auto=
spring.aop.proxy-target-class=

# FILE ENCODING (FileEncodingApplicationListener)
spring.mandatory-file-encoding=false

# SPRING SOCIAL (SocialWebAutoConfiguration)
spring.social.auto-connection-views=true # Set to true for default connection views or false if you provide your own

# SPRING SOCIAL FACEBOOK (FacebookAutoConfiguration)
spring.social.facebook.app-id= # your application's Facebook App ID
spring.social.facebook.app-secret= # your application's Facebook App Secret

# SPRING SOCIAL LINKEDIN (LinkedInAutoConfiguration)
spring.social.linkedin.app-id= # your application's LinkedIn App ID
spring.social.linkedin.app-secret= # your application's LinkedIn App Secret

# SPRING SOCIAL TWITTER (TwitterAutoConfiguration)
spring.social.twitter.app-id= # your application's Twitter App ID
spring.social.twitter.app-secret= # your application's Twitter App Secret

# SPRING MOBILE SITE PREFERENCE (SitePreferenceAutoConfiguration)
spring.mobile.sitepreference.enabled=true # enabled by default

# SPRING MOBILE DEVICE VIEWS (DeviceDelegatingViewResolverAutoConfiguration)
spring.mobile.devicedelegatingviewresolver.enabled=true # disabled by default
spring.mobile.devicedelegatingviewresolver.normalPrefix=
spring.mobile.devicedelegatingviewresolver.normalSuffix=
spring.mobile.devicedelegatingviewresolver.mobilePrefix=mobile/
spring.mobile.devicedelegatingviewresolver.mobileSuffix=
spring.mobile.devicedelegatingviewresolver.tabletPrefix=tablet/
spring.mobile.devicedelegatingviewresolver.tabletSuffix=

# ----------------------------------------
# ACTUATOR PROPERTIES
# ----------------------------------------

# MANAGEMENT HTTP SERVER (ManagementServerProperties)
management.port= # defaults to 'server.port'
management.address= # bind to a specific NIC
management.contextPath= # default to '/'

# ENDPOINTS (AbstractEndpoint subclasses)
endpoints.autoconfig.id=autoconfig
endpoints.autoconfig.sensitive=true
endpoints.autoconfig.enabled=true
endpoints.beans.id=beans
endpoints.beans.sensitive=true
endpoints.beans.enabled=true
endpoints.configprops.id=configprops
endpoints.configprops.sensitive=true
endpoints.configprops.enabled=true
endpoints.configprops.keys-to-sanitize=password,secret
endpoints.dump.id=dump
endpoints.dump.sensitive=true
endpoints.dump.enabled=true
endpoints.env.id=env
endpoints.env.sensitive=true
endpoints.env.enabled=true
endpoints.health.id=health
endpoints.health.sensitive=false
endpoints.health.enabled=true
endpoints.info.id=info
endpoints.info.sensitive=false
endpoints.info.enabled=true
endpoints.metrics.id=metrics
endpoints.metrics.sensitive=true
endpoints.metrics.enabled=true
endpoints.shutdown.id=shutdown
endpoints.shutdown.sensitive=true
endpoints.shutdown.enabled=false
endpoints.trace.id=trace
endpoints.trace.sensitive=true
endpoints.trace.enabled=true

# MVC ONLY ENDPOINTS
endpoints.jolokia.path=jolokia
endpoints.jolokia.sensitive=true
endpoints.jolokia.enabled=true # when using Jolokia
endpoints.error.path=/error

# JMX ENDPOINT (EndpointMBeanExportProperties)
endpoints.jmx.enabled=true
endpoints.jmx.domain= # the JMX domain, defaults to 'org.springboot'
endpoints.jmx.unique-names=false
endpoints.jmx.enabled=true
endpoints.jmx.staticNames=

# JOLOKIA (JolokiaProperties)
jolokia.config.*= # See Jolokia manual

# REMOTE SHELL
shell.auth=simple # jaas, key, simple, spring
shell.command-refresh-interval=-1
shell.command-path-pattern= # classpath*:/commands/**, classpath*:/crash/commands/**
shell.config-path-patterns= # classpath*:/crash/*
shell.disabled-plugins=false # don't expose plugins
shell.ssh.enabled= # ssh settings ...
shell.ssh.keyPath=
shell.ssh.port=
shell.telnet.enabled= # telnet settings ...
shell.telnet.port=
shell.auth.jaas.domain= # authentication settings ...
shell.auth.key.path=
shell.auth.simple.user.name=
shell.auth.simple.user.password=
shell.auth.spring.roles=

# GIT INFO
spring.git.properties= # resource ref to generated git info properties file