【Spring Boot && Spring Cloud系列】构建Springboot项目 实现restful风格接口

项目代码如下：

1 package hello;
2
3 import org.springframework.boot.SpringApplication;
4 import org.springframework.boot.autoconfigure.SpringBootApplication;
5
6 @SpringBootApplication  // same as @Configuration @EnableAutoConfiguration @ComponentScan
7
8 public class Application {
9
10     public static void main(String[] args) {
11          SpringApplication.run(Application.class, args);
12     }
13
14 }

1 package hello;
2
3 public class Greeting {
4 private  long id;
5 private  String content;
6 public Greeting(long id, String content) {
7     super();
8     this.id = id;
9     this.content = content;
10 }
11 public long getId() {
12     return id;
13 }
14 public void setId(long id) {
15     this.id = id;
16 }
17 public String getContent() {
18     return content;
19 }
20 public void setContent(String content) {
21     this.content = content;
22 }
23
24 }

1 package hello;
2
3 import java.util.concurrent.atomic.AtomicLong;
4
5 import org.springframework.web.bind.annotation.RequestMapping;
6 import org.springframework.web.bind.annotation.RequestParam;
7 import org.springframework.web.bind.annotation.RestController;
8
9 @RestController // shorthand for @Controller and @ResponseBody rolled together
10 public class GreetingController {
11
12     private static final String template="Hello,%s!";
13     private final AtomicLong counter=new AtomicLong();
14
15     @RequestMapping("/greeting")
16     public Greeting greeting(@RequestParam(value="name",defaultValue="World")String name){
17         System.out.println("-------------------------");
18         return new Greeting(counter.incrementAndGet(),String.format(template, name));
19     }
20 }

1 <?xml version="1.0" encoding="UTF-8"?>
2 <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
3     xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"> 4     <modelVersion>4.0.0</modelVersion>
5
6     <groupId>com.slp</groupId>
7     <artifactId>restSpringDemo1</artifactId>
8     <version>0.1.0</version>
9
10     <parent>
11         <groupId>org.springframework.boot</groupId>
12         <artifactId>spring-boot-starter-parent</artifactId>
13         <version>1.4.1.RELEASE</version>
14     </parent>
15
16     <dependencies>
17         <dependency>
18             <groupId>org.springframework.boot</groupId>
19             <artifactId>spring-boot-starter-web</artifactId>
20         </dependency>
21         <dependency>
22             <groupId>org.springframework.boot</groupId>
23             <artifactId>spring-boot-starter-test</artifactId>
24             <scope>test</scope>
25         </dependency>
26         <dependency>
27             <groupId>com.jayway.jsonpath</groupId>
28             <artifactId>json-path</artifactId>
29             <scope>test</scope>
30         </dependency>
31     </dependencies>
32
33     <properties>
34         <java.version>1.8</java.version>
35     </properties>
36
37
38     <build>
39         <plugins>
40             <plugin>
41                 <groupId>org.springframework.boot</groupId>
42                 <artifactId>spring-boot-maven-plugin</artifactId>
43             </plugin>
44         </plugins>
45     </build>
46
47     <repositories>
48         <repository>
49             <id>spring-releases</id>
50             <url>https://repo.spring.io/libs-release</url>
51         </repository>
52     </repositories>
53     <pluginRepositories>
54         <pluginRepository>
55             <id>spring-releases</id>
56             <url>https://repo.spring.io/libs-release</url>
57         </pluginRepository>
58     </pluginRepositories>
59 </project>

在Application.java中run as java application 出现：

1  .   ____          _            __ _ _
2  /\\ / ___'_ __ _ _(_)_ __  __ _ \ \ \ \
3 ( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \
4  \\/  ___)| |_)| | | | | || (_| |  ) ) ) )
5   '  |____| .__|_| |_|_| |_\__, | / / / /
6  =========|_|==============|___/=/_/_/_/
7  :: Spring Boot ::        (v1.4.1.RELEASE)
8
9 2016-10-13 11:19:16.510  INFO 9864 --- [           main] hello.Application                        : Starting Application on QH-20160418YQMB with PID 9864 (started by sanglp in D:\rest风格的apring项目\restSpringDemo1)
10 2016-10-13 11:19:16.525  INFO 9864 --- [           main] hello.Application                        : No active profile set, falling back to default profiles: default
11 2016-10-13 11:19:16.713  INFO 9864 --- [           main] ationConfigEmbeddedWebApplicationContext : Refreshing org.springframework.boot.context.embedded.AnnotationConfigEmbeddedWebApplicationContext@72f926e6: startup date [Thu Oct 13 11:19:16 CST 2016]; root of context hierarchy
12 2016-10-13 11:19:19.691  INFO 9864 --- [           main] s.b.c.e.t.TomcatEmbeddedServletContainer : Tomcat initialized with port(s): 8080 (http)
13 2016-10-13 11:19:19.710  INFO 9864 --- [           main] o.apache.catalina.core.StandardService   : Starting service Tomcat
14 2016-10-13 11:19:19.710  INFO 9864 --- [           main] org.apache.catalina.core.StandardEngine  : Starting Servlet Engine: Apache Tomcat/8.0.35
15 2016-10-13 11:19:20.148  INFO 9864 --- [ost-startStop-1] org.apache.jasper.servlet.TldScanner     : At least one JAR was scanned for TLDs yet contained no TLDs. Enable debug logging for this logger for a complete list of JARs that were scanned but no TLDs were found in them. Skipping unneeded JARs during scanning can improve startup time and JSP compilation time.
16 2016-10-13 11:19:20.148  INFO 9864 --- [ost-startStop-1] o.a.c.c.C.[Tomcat].[localhost].[/]       : Initializing Spring embedded WebApplicationContext
17 2016-10-13 11:19:20.148  INFO 9864 --- [ost-startStop-1] o.s.web.context.ContextLoader            : Root WebApplicationContext: initialization completed in 3451 ms
18 2016-10-13 11:19:20.382  INFO 9864 --- [ost-startStop-1] o.s.b.w.servlet.ServletRegistrationBean  : Mapping servlet: 'dispatcherServlet' to [/]
19 2016-10-13 11:19:20.398  INFO 9864 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean   : Mapping filter: 'characterEncodingFilter' to: [/*]
20 2016-10-13 11:19:20.398  INFO 9864 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean   : Mapping filter: 'hiddenHttpMethodFilter' to: [/*]
21 2016-10-13 11:19:20.398  INFO 9864 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean   : Mapping filter: 'httpPutFormContentFilter' to: [/*]
22 2016-10-13 11:19:20.398  INFO 9864 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean   : Mapping filter: 'requestContextFilter' to: [/*]
23 2016-10-13 11:19:20.866  INFO 9864 --- [           main] s.w.s.m.m.a.RequestMappingHandlerAdapter : Looking for @ControllerAdvice: org.springframework.boot.context.embedded.AnnotationConfigEmbeddedWebApplicationContext@72f926e6: startup date [Thu Oct 13 11:19:16 CST 2016]; root of context hierarchy
24 2016-10-13 11:19:20.986  INFO 9864 --- [           main] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/greeting]}" onto public hello.Greeting hello.GreetingController.greeting(java.lang.String)
25 2016-10-13 11:19:20.986  INFO 9864 --- [           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)
26 2016-10-13 11:19:20.986  INFO 9864 --- [           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)
27 2016-10-13 11:19:21.033  INFO 9864 --- [           main] o.s.w.s.handler.SimpleUrlHandlerMapping  : Mapped URL path [/webjars/**] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]
28 2016-10-13 11:19:21.033  INFO 9864 --- [           main] o.s.w.s.handler.SimpleUrlHandlerMapping  : Mapped URL path [/**] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]
29 2016-10-13 11:19:21.095  INFO 9864 --- [           main] o.s.w.s.handler.SimpleUrlHandlerMapping  : Mapped URL path [/**/favicon.ico] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]
30 2016-10-13 11:19:21.307  INFO 9864 --- [           main] o.s.j.e.a.AnnotationMBeanExporter        : Registering beans for JMX exposure on startup
31 2016-10-13 11:19:21.463  INFO 9864 --- [           main] s.b.c.e.t.TomcatEmbeddedServletContainer : Tomcat started on port(s): 8080 (http)
32 2016-10-13 11:19:21.479  INFO 9864 --- [           main] hello.Application                        : Started Application in 6.497 seconds (JVM running for 7.83)
33 2016-10-13 11:21:46.570  INFO 9864 --- [nio-8080-exec-1] o.a.c.c.C.[Tomcat].[localhost].[/]       : Initializing Spring FrameworkServlet 'dispatcherServlet'
34 2016-10-13 11:21:46.570  INFO 9864 --- [nio-8080-exec-1] o.s.web.servlet.DispatcherServlet        : FrameworkServlet 'dispatcherServlet': initialization started
35 2016-10-13 11:21:46.622  INFO 9864 --- [nio-8080-exec-1] o.s.web.servlet.DispatcherServlet        : FrameworkServlet 'dispatcherServlet': initialization completed in 51 ms

表示启动成功，这是就可以访问了 http://localhost:8080/greeting?name=xxb
会出现如下结果：

{"id":3,"content":"Hello,xuxiaobo!"}

这是一个纯java的项目，不需要启动tomcat也可以执行访问

首先你需要建立一个基本的项目，你可以使用任何你喜欢的方式去构造Spring项目，这里使用的是Maven.如果你不熟悉Maven的话请移步 Building Java Projects with Maven.

创建项目目录结构

在你所选的项目目录中，创建如下的子目录结构；例如在unix系统中使用mkdir -p src/main/java/hello。

└── src
└── main
└── java
└── hello

pom.xml

<?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>org.springframework</groupId>
<artifactId>gs-rest-service</artifactId>
<version>0.1.0</version>

<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>1.4.1.RELEASE</version>
</parent>

<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
<dependency>
<groupId>com.jayway.jsonpath</groupId>
<artifactId>json-path</artifactId>
<scope>test</scope>
</dependency>
</dependencies>

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

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

<repositories>
<repository>
<id>spring-releases</id>
<url>https://repo.spring.io/libs-release</url>
</repository>
</repositories>
<pluginRepositories>
<pluginRepository>
<id>spring-releases</id>
<url>https://repo.spring.io/libs-release</url>
</pluginRepository>
</pluginRepositories>
</project>

Spring Boot的maven插件提供了很多便利的特性：

它包含了路径中的所有jar文件，使用“über-jar”。它使得执行和转换服务非常便利。

它查询

public static void main()

方法去标志为一个可执行的类

它提供了一个内置的匹配Spring boot 依赖的版本，你可以选择任何你希望的版本，但是默认情况下它会选择Boot的版本设置变量。