Java

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基础概念

1. 依赖注入(DI)

ApplicationContext Spring IOC 容器负责创建Bean和维护Bean之间的依赖关系

2. 控制反转(IOC)

通过容器来实现对象组件的装配和管理,是通过依赖注入实现的

3. 注解配置

3.1 声明

@Component
@Service
@Repository
@Controller

3.2 注入

@Autowired
@Inject
@Resource

4. Java 配置

4.1 概念

Spring 4.x 推荐使用Java 配置

@Configuration,相当与Spring配置的xml文件
@Bean,当前方法返回值为一个Bean

4.2 原则

全局配置使用Java 配置
业务Bean使用注解配置

4.3. AOP

@Aspect
@After, @Before, @Around

Spring 常用配置

1. @Scope 新建Bean 的实例

2. @Value Spring EL,注入资源

3. 事件

自定义事件,ApplicationEvent
事件监听器, ApplicationListener
容器发布事件

4. @Profile,实例化不同的Bean

Spring 高级

1. 多线程

使用ThreadPoolTaskExecutor 实现一个基于线程池的TaskExecutor,然后@EnableAsync开启异步支持并通过Bean中的@Async注解来声明一个异步任务

2. 计划任务

@EnableScheduling 开启对计划任务的支持
@Scheduled, 声明计划任务

3. 条件注解,@Conditional,根据满足某一个特定条件创建一个特定的Bean

4. 组合注解与元注解

元注解,最原来的注解
组合注解,多个元注解注解后的注解,应用到Bean

Spring Boot 基础概念

独立运行Spring 项目，只需要java -jar xxx.jar
内嵌Servlet 容器，无需使用war包部署
使用starter 简化maven 配置
提供基于http, ssh, telnet 对项目进行监控
无代码生成和xml配置

Hello Spring Boot ！

1. pom.xml

<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>peerslee</groupId>  <artifactId>yierling</artifactId>  <version>0.0.1-SNAPSHOT</version>  <packaging>jar</packaging>  <name>yierling</name>  <url>http://maven.apache.org</url>  <!-- 父类提供相关的默认的maven 配置，常用的包依赖可以省去version 标签  -->  <parent>    <groupId>org.springframework.boot</groupId>    <artifactId>spring-boot-starter-parent</artifactId>    <version>1.3.3.RELEASE</version>  </parent>  <properties>  <java.version>1.8</java.version>    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>  </properties>  <dependencies><!-- Web 应用 --><dependency>    <groupId>org.springframework.boot</groupId>    <artifactId>spring-boot-starter-web</artifactId></dependency><!-- https://mvnrepository.com/artifact/junit/junit --><dependency>    <groupId>junit</groupId>    <artifactId>junit</artifactId></dependency>  </dependencies>  <!-- spring boot 编译插件 -->  <build>    <plugins>      <plugin>        <groupId>org.springframework.boot</groupId>        <artifactId>spring-boot-maven-plugin</artifactId>      </plugin>    </plugins>  </build></project>

2. App.Java

package peerslee.yierling;import org.springframework.boot.SpringApplication;import org.springframework.boot.autoconfigure.SpringBootApplication;import org.springframework.web.bind.annotation.RequestMapping;import org.springframework.web.bind.annotation.RestController;/** * Hello world! * */@RestController@SpringBootApplication //Spring Boot 项目和核心注解，开启自动配置public class App {@RequestMapping("/")String index() {return "Hello Spring Boot！";}    public static void main( String[] args ) throws Exception    {        SpringApplication.run(App.class, args);    }}

3. Run

  .   ____          _            __ _ _ /\\ / ___'_ __ _ _(_)_ __  __ _ \ \ \ \( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \ \\/  ___)| |_)| | | | | || (_| |  ) ) ) )  '  |____| .__|_| |_|_| |_\__, | / / / / =========|_|==============|___/=/_/_/_/ :: Spring Boot ::        (v1.3.3.RELEASE)2017-06-04 15:28:13.006  INFO 7312 --- [           main] peerslee.yierling.App                    : Starting App on WIN10-703302300 with PID 7312 (D:\code\eclipse\yierling\target\classes started by Administrator in D:\code\eclipse\yierling)2017-06-04 15:28:13.008  INFO 7312 --- [           main] peerslee.yierling.App                    : No active profile set, falling back to default profiles: default2017-06-04 15:28:13.052  INFO 7312 --- [           main] ationConfigEmbeddedWebApplicationContext : Refreshing org.springframework.boot.context.embedded.AnnotationConfigEmbeddedWebApplicationContext@df27fae: startup date [Sun Jun 04 15:28:13 CST 2017]; root of context hierarchy2017-06-04 15:28:13.575  INFO 7312 --- [           main] o.s.b.f.s.DefaultListableBeanFactory     : Overriding bean definition for bean 'beanNameViewResolver' with a different definition: replacing [Root bean: class [null]; scope=; abstract=false; lazyInit=false; autowireMode=3; dependencyCheck=0; autowireCandidate=true; primary=false; factoryBeanName=org.springframework.boot.autoconfigure.web.ErrorMvcAutoConfiguration$WhitelabelErrorViewConfiguration; factoryMethodName=beanNameViewResolver; initMethodName=null; destroyMethodName=(inferred); defined in class path resource [org/springframework/boot/autoconfigure/web/ErrorMvcAutoConfiguration$WhitelabelErrorViewConfiguration.class]] with [Root bean: class [null]; scope=; abstract=false; lazyInit=false; autowireMode=3; dependencyCheck=0; autowireCandidate=true; primary=false; factoryBeanName=org.springframework.boot.autoconfigure.web.WebMvcAutoConfiguration$WebMvcAutoConfigurationAdapter; factoryMethodName=beanNameViewResolver; initMethodName=null; destroyMethodName=(inferred); defined in class path resource [org/springframework/boot/autoconfigure/web/WebMvcAutoConfiguration$WebMvcAutoConfigurationAdapter.class]]2017-06-04 15:28:14.039  INFO 7312 --- [           main] s.b.c.e.t.TomcatEmbeddedServletContainer : Tomcat initialized with port(s): 8080 (http)2017-06-04 15:28:14.091  INFO 7312 --- [           main] o.apache.catalina.core.StandardService   : Starting service Tomcat2017-06-04 15:28:14.092  INFO 7312 --- [           main] org.apache.catalina.core.StandardEngine  : Starting Servlet Engine: Apache Tomcat/8.0.322017-06-04 15:28:14.191  INFO 7312 --- [ost-startStop-1] o.a.c.c.C.[Tomcat].[localhost].[/]       : Initializing Spring embedded WebApplicationContext2017-06-04 15:28:14.191  INFO 7312 --- [ost-startStop-1] o.s.web.context.ContextLoader            : Root WebApplicationContext: initialization completed in 1142 ms2017-06-04 15:28:14.445  INFO 7312 --- [ost-startStop-1] o.s.b.c.e.ServletRegistrationBean        : Mapping servlet: 'dispatcherServlet' to [/]2017-06-04 15:28:14.451  INFO 7312 --- [ost-startStop-1] o.s.b.c.embedded.FilterRegistrationBean  : Mapping filter: 'characterEncodingFilter' to: [/*]2017-06-04 15:28:14.452  INFO 7312 --- [ost-startStop-1] o.s.b.c.embedded.FilterRegistrationBean  : Mapping filter: 'hiddenHttpMethodFilter' to: [/*]2017-06-04 15:28:14.452  INFO 7312 --- [ost-startStop-1] o.s.b.c.embedded.FilterRegistrationBean  : Mapping filter: 'httpPutFormContentFilter' to: [/*]2017-06-04 15:28:14.452  INFO 7312 --- [ost-startStop-1] o.s.b.c.embedded.FilterRegistrationBean  : Mapping filter: 'requestContextFilter' to: [/*]2017-06-04 15:28:14.672  INFO 7312 --- [           main] s.w.s.m.m.a.RequestMappingHandlerAdapter : Looking for @ControllerAdvice: org.springframework.boot.context.embedded.AnnotationConfigEmbeddedWebApplicationContext@df27fae: startup date [Sun Jun 04 15:28:13 CST 2017]; root of context hierarchy2017-06-04 15:28:14.722  INFO 7312 --- [           main] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/]}" onto java.lang.String peerslee.yierling.App.index()2017-06-04 15:28:14.725  INFO 7312 --- [           main] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/error]}" onto public org.springframework.http.ResponseEntity<java.util.Map<java.lang.String, java.lang.Object>> org.springframework.boot.autoconfigure.web.BasicErrorController.error(javax.servlet.http.HttpServletRequest)2017-06-04 15:28:14.725  INFO 7312 --- [           main] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/error],produces=[text/html]}" onto public org.springframework.web.servlet.ModelAndView org.springframework.boot.autoconfigure.web.BasicErrorController.errorHtml(javax.servlet.http.HttpServletRequest,javax.servlet.http.HttpServletResponse)2017-06-04 15:28:14.746  INFO 7312 --- [           main] o.s.w.s.handler.SimpleUrlHandlerMapping  : Mapped URL path [/webjars/**] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]2017-06-04 15:28:14.746  INFO 7312 --- [           main] o.s.w.s.handler.SimpleUrlHandlerMapping  : Mapped URL path [/**] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]2017-06-04 15:28:14.778  INFO 7312 --- [           main] o.s.w.s.handler.SimpleUrlHandlerMapping  : Mapped URL path [/**/favicon.ico] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]2017-06-04 15:28:14.861  INFO 7312 --- [           main] o.s.j.e.a.AnnotationMBeanExporter        : Registering beans for JMX exposure on startup2017-06-04 15:28:14.929  INFO 7312 --- [           main] s.b.c.e.t.TomcatEmbeddedServletContainer : Tomcat started on port(s): 8080 (http)2017-06-04 15:28:14.934  INFO 7312 --- [           main] peerslee.yierling.App                    : Started App in 2.134 seconds (JVM running for 2.432)2017-06-04 15:28:36.706  INFO 7312 --- [nio-8080-exec-1] o.a.c.c.C.[Tomcat].[localhost].[/]       : Initializing Spring FrameworkServlet 'dispatcherServlet'2017-06-04 15:28:36.707  INFO 7312 --- [nio-8080-exec-1] o.s.web.servlet.DispatcherServlet        : FrameworkServlet 'dispatcherServlet': initialization started2017-06-04 15:28:36.721  INFO 7312 --- [nio-8080-exec-1] o.s.web.servlet.DispatcherServlet        : FrameworkServlet 'dispatcherServlet': initialization completed in 14 ms

4. 测试

http://localhost:8080/

问题

1. 使用maven 更新项目

Project configuration is not up-to-date with pom.xml. Select: Maven->Update Project... from the project context menu or use Quick Fix.yierlingline 1Maven Configuration Problem

2. localhost:8080拒绝访问解决方案（win10系统）

打开“我的电脑”，选择左上角的“计算机”中的“卸载或更改程序”。
点击“启用或关闭Windows功能”。
选中“Internet Information Service”

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