springboot 入门

• 使用maven构建project项目, 配置aliyun仓库, 不赘述
• springboot 版本需要: jdk1.7+, maven3.2+ , gradle2.9+
• 配置文件

1. 引入父包, 放在<project>标签内, 期内包含大量配置好的依赖, 在自己项目中添加这些一来是不需要写<version>

     <parent>
           <groupId>org.springframework.boot</groupId>
           <artifactId>spring-boot-starter-parent</artifactId>
           <!--!这里版本不能使用properties配置-->
           <version>1.5..RELEASE</version>
     </parent>

   有时候我们自己公司内有父pom, 不能直接添加parent, 可以通过以下方式

   <dependencyManagement>
        <dependencies>
           <dependency>
               <!-- Import dependency management from Spring Boot -->
               <groupId>org.springframework.boot</groupId>
               <artifactId>spring-boot-dependencies</artifactId>
               <version>1.5.2.RELEASE</version>
               <type>pom</type>
               <scope>import</scope>
           </dependency>
       </dependencies>
   </dependencyManagement>

2. 引入web启动包, 因为我们开发的是web工程，所以需要在pom.xml中引入spring-boot-starter-web,spring官方解释说spring-boot-start-web包含了spring webmvc和tomcat等web开发的特性。

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

3. 加入仓库配置, 如果是release版本不需要

   (you don't need this if you are using a .RELEASE version)

   <repositories>
           <repository>
               <id>spring-snapshots</id>
               <url>http://repo.spring.io/snapshot</url>
               <snapshots><enabled>true</enabled></snapshots>
           </repository>
           <repository>
               <id>spring-milestones</id>
               <url>http://repo.spring.io/milestone</url>
           </repository>
       </repositories>
       <pluginRepositories>
           <pluginRepository>
               <id>spring-snapshots</id>
               <url>http://repo.spring.io/snapshot</url>
           </pluginRepository>
           <pluginRepository>
               <id>spring-milestones</id>
               <url>http://repo.spring.io/milestone</url>
           </pluginRepository>
       </pluginRepositories>

4. 直接使用Main启动spring, plugin需要添加, 如果使用 spring-boot:run 不需要此配置

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

5. 程序主入口

6. @RestController  //springmvc 注解, 返回给调用者字符串
   @SpringBootApplication // 自动给程序添加默认属性
   public class App {  
   
     @RequestMapping("/")
     public String hello(){
       return "Hello world!";
     }  
   
     public static void main(String[] args) {
       SpringApplication.run(App.class, args);
     }
   }  

7. 启动: 运行main函数
   1. 　　run as : spring-boot:run
   2. 　　右键, run as java Application

配置pom.xml文件, 使用maven-compiler-plugins插件锁定jdk版本和maven-surefire-plugins插件配置maven-test

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

    <groupId>com.wenbronk</groupId>
    <artifactId>SpringBootTest</artifactId>
    <version>0.0.1-SNAPSHOT</version>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>1.3.5.RELEASE</version>
    </parent>

    <!-- Additional lines to be added here... -->
     <dependencies>
         <!-- web 启动的jar包 -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>

    <!--jpa的jar包 ，操作数据库的，类似hibernate-->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-jpa</artifactId>
        </dependency>

        <!--mysql驱动-->
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
        </dependency>

        <!--thymeleaf模板jar，是很不错的html数据传递取值，类似jsp的jstl-->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-thymeleaf</artifactId>
        </dependency>
    </dependencies>

    <!--maven的插件-->
    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>

    <!-- 配置java版本 不配置的话默认父类配置的是1.6-->
    <pluginManagement>
      <plugins>
        <plugin>
          <artifactId>maven-compiler-plugin</artifactId>
          <configuration>
            <source>1.7</source>
            <target>1.7</target>
          </configuration>
        </plugin>
      </plugins>
    </pluginManagement>
  </build>

</project>

然后运行maven dependecy:tree, 下载依赖到本地仓库中

注意:

• java.version属性
  • 　　spring 默认 使用jdk1.6, 如果想使用1.8, 需要如下配置

    <properties>
        <java.version>1.8</java.version>
    </properties>

  • 添加spring-boot-starter-web依赖

　　　　　　　spring通过spring-boot-starter-*来支持具体的某个功能

　　　　　　　　具体请参照: http://docs.spring.io/spring-boot/docs/1.2.3.RELEASE/reference/html/using-boot-build-systems.html#using-boot-starter-poms

错误: 

1. 使用1.5.1版本一直报错

   [INFO] Scanning for projects...
   [ERROR] [ERROR] Some problems were encountered while processing the POMs:
   [FATAL] Non-parseable POM C:\Users\231\.m2\repository\org\springframework\boot\spring-boot-dependencies\1.5.1.RELEASE\spring-boot-dependencies-1.5.1.RELEASE.pom: only whitespace content allowed before start tag and not o (position: START_DOCUMENT seen o... @1:1)  @ C:\Users\231\.m2\repository\org\springframework\boot\spring-boot-dependencies\1.5.1.RELEASE\spring-boot-dependencies-1.5.1.RELEASE.pom, line 1, column 1
    @
   [ERROR] The build could not read 1 project -> [Help 1]
   [ERROR]
   [ERROR]   The project com.example:myproject:0.0.1-SNAPSHOT (E:\iwhere\SpringBootTest\pom.xml) has 1 error
   [ERROR]     Non-parseable POM C:\Users\231\.m2\repository\org\springframework\boot\spring-boot-dependencies\1.5.1.RELEASE\spring-boot-dependencies-1.5.1.RELEASE.pom: only whitespace content allowed before start tag and not o (position: START_DOCUMENT seen o... @1:1)  @ C:\Users\231\.m2\repository\org\springframework\boot\spring-boot-dependencies\1.5.1.RELEASE\spring-boot-dependencies-1.5.1.RELEASE.pom, line 1, column 1 -> [Help 2]
   [ERROR]
   [ERROR] To see the full stack trace of the errors, re-run Maven with the -e switch.
   [ERROR] Re-run Maven using the -X switch to enable full debug logging.
   [ERROR]
   [ERROR] For more information about the errors and possible solutions, please read the following articles:
   [ERROR] [Help 1] http://cwiki.apache.org/confluence/display/MAVEN/ProjectBuildingException
   [ERROR] [Help 2] http://cwiki.apache.org/confluence/display/MAVEN/ModelParseException

   解决: 更换版本为1.5.2就好了.....