Spring Boot 教程：服務(wù)組件
【注】本文譯自： https://www.tutorialspoint.com/spring_boot/spring_boot_service_components.htm
? ? 服務(wù)組件是包含?@Service 注解的類文件。這些類文件可用在與?@RestController 類文件所不同的層來編寫業(yè)務(wù)邏輯。創(chuàng)建服務(wù)組件類文件如下所示：
public?interface?ProductService?{
}
? ? 以?@Service 注解實(shí)現(xiàn)接口的類如下所示：
@Service
public?class?ProductServiceImpl?implements?ProductService?{
}
? ? 回顧以前的教程中，我們使用產(chǎn)品服務(wù) API(s) 來存儲(chǔ)、獲取、更新和刪除產(chǎn)品。我們在 @RestController 類文件自身中編寫業(yè)務(wù)邏輯。現(xiàn)在我們要把業(yè)務(wù)邏輯代碼從控制器移到服務(wù)組件。
? ? 你可以創(chuàng)建一個(gè)接口，包含增加、編輯、獲取和刪除方法，示例代碼如下：
package?com.tutorialspoint.demo.service;
import?java.util.Collection;
import?com.tutorialspoint.demo.model.Product;
public?interface?ProductService?{
???public?abstract?void?createProduct(Product?product);
???public?abstract?void?updateProduct(String?id,?Product?product);
???public?abstract?void?deleteProduct(String?id);
???public?abstract?Collection<Product>?getProducts();
}
? ? 以下代碼將讓你創(chuàng)建一個(gè)以 @Service 注解來實(shí)現(xiàn)?ProductService 接口的類，用以編寫存儲(chǔ)、獲取、刪除和更新產(chǎn)品。
package?com.tutorialspoint.demo.service;
import?java.util.Collection;
import?java.util.HashMap;
import?java.util.Map;
import?org.springframework.stereotype.Service;
import?com.tutorialspoint.demo.model.Product;
@Service
public?class?ProductServiceImpl?implements?ProductService?{
???private?static?Map<String,?Product>?productRepo?=?new?HashMap<>();
???static?{
??????Product?honey?=?new?Product();
??????honey.setId("1");
??????honey.setName("Honey");
??????productRepo.put(honey.getId(),?honey);
??????Product?almond?=?new?Product();
??????almond.setId("2");
??????almond.setName("Almond");
??????productRepo.put(almond.getId(),?almond);
???}
???@Override
???public?void?createProduct(Product?product)?{
??????productRepo.put(product.getId(),?product);
???}
???@Override
???public?void?updateProduct(String?id,?Product?product)?{
??????productRepo.remove(id);
??????product.setId(id);
??????productRepo.put(id,?product);
???}
???@Override
???public?void?deleteProduct(String?id)?{
??????productRepo.remove(id);
???}
???@Override
???public?Collection<Product>?getProducts()?{
??????return?productRepo.values();
???}
}
? ? 以里的代碼展示了?Rest Controller 類文件，我們用 @Autowired 來自動(dòng)注入 ProductService 接口并調(diào)用其方法。
package?com.tutorialspoint.demo.controller;
import?org.springframework.beans.factory.annotation.Autowired;
import?org.springframework.http.HttpStatus;
import?org.springframework.http.ResponseEntity;
import?org.springframework.web.bind.annotation.PathVariable;
import?org.springframework.web.bind.annotation.RequestBody;
import?org.springframework.web.bind.annotation.RequestMapping;
import?org.springframework.web.bind.annotation.RequestMethod;
import?org.springframework.web.bind.annotation.RestController;
import?com.tutorialspoint.demo.model.Product;
import?com.tutorialspoint.demo.service.ProductService;
@RestController
public?class?ProductServiceController?{
???@Autowired
???ProductService?productService;
???@RequestMapping(value?=?"/products")
???public?ResponseEntity<Object>?getProduct()?{
??????return?new?ResponseEntity<>(productService.getProducts(),?HttpStatus.OK);
???}
???@RequestMapping(value?=?"/products/{id}",?method?=?RequestMethod.PUT)
???public?ResponseEntity<Object>?
??????updateProduct(@PathVariable("id")?String?id,?@RequestBody?Product?product)?{
??????
??????productService.updateProduct(id,?product);
??????return?new?ResponseEntity<>("Product?is?updated?successsfully",?HttpStatus.OK);
???}
???@RequestMapping(value?=?"/products/{id}",?method?=?RequestMethod.DELETE)
???public?ResponseEntity<Object>?delete(@PathVariable("id")?String?id)?{
??????productService.deleteProduct(id);
??????return?new?ResponseEntity<>("Product?is?deleted?successsfully",?HttpStatus.OK);
???}
???@RequestMapping(value?=?"/products",?method?=?RequestMethod.POST)
???public?ResponseEntity<Object>?createProduct(@RequestBody?Product?product)?{
??????productService.createProduct(product);
??????return?new?ResponseEntity<>("Product?is?created?successfully",?HttpStatus.CREATED);
???}
}
? ??POJO class – Product.java 代碼在此：
package?com.tutorialspoint.demo.model;
public?class?Product?{
???private?String?id;
???private?String?name;
???public?String?getId()?{
??????return?id;
???}
???public?void?setId(String?id)?{
??????this.id?=?id;
???}
???public?String?getName()?{
??????return?name;
???}
???public?void?setName(String?name)?{
??????this.name?=?name;
???}
}
? ?主?Spring Boot 應(yīng)用如下：
package?com.tutorialspoint.demo;
import?org.springframework.boot.SpringApplication;
import?org.springframework.boot.autoconfigure.SpringBootApplication;
@SpringBootApplication
public?class?DemoApplication?{
???public?static?void?main(String[]?args)?{
??????SpringApplication.run(DemoApplication.class,?args);
???}
}
? ??Maven build – pom.xml 代碼如下所示：
<?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.tutorialspoint</groupId>
???<artifactId>demo</artifactId>
???<version>0.0.1-SNAPSHOT</version>
???<packaging>jar</packaging>
???<name>demo</name>
???<description>Demo?project?for?Spring?Boot</description>
???<parent>
??????<groupId>org.springframework.boot</groupId>
??????<artifactId>spring-boot-starter-parent</artifactId>
??????<version>1.5.8.RELEASE</version>
??????<relativePath/>?
???</parent>
???<properties>
??????<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
??????<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
??????<java.version>1.8</java.version>
???</properties>
???<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>
???</dependencies>
???<build>
??????<plugins>
?????????<plugin>
????????????<groupId>org.springframework.boot</groupId>
????????????<artifactId>spring-boot-maven-plugin</artifactId>
?????????</plugin>
??????</plugins>
???</build>
</project>
? ??Gradle Build – build.gradle 代碼如下：
buildscript?{
???ext?{
??????springBootVersion?=?'1.5.8.RELEASE'
???}
???repositories?{
??????mavenCentral()
???}
???dependencies?{
??????classpath("org.springframework.boot:spring-boot-gradle-plugin:${springBootVersion}")
???}
}
apply?plugin:?'java'
apply?plugin:?'eclipse'
apply?plugin:?'org.springframework.boot'
group?=?'com.tutorialspoint'
version?=?'0.0.1-SNAPSHOT'
sourceCompatibility?=?1.8
repositories?{
???mavenCentral()
}
dependencies?{
???compile('org.springframework.boot:spring-boot-starter-web')
???testCompile('org.springframework.boot:spring-boot-starter-test')
}
? ?現(xiàn)在你可以使用 Maven 或 Gradle 命令創(chuàng)建可執(zhí)行?executable JAR 文件并運(yùn)行 Spring Boot 應(yīng)用了：
? ?Maven 命令如下：
mvn clean install
? ?在 “BUILD SUCCESS” 之后，你可以在 target 目錄下找到 JAR 文件。
? ?Gradle 可以使用以下命令：
gradle clean build
? ?在 “BUILD SUCCESSFUL” 之后，你可以在?build/libs 目錄下找到?JAR 文件。
? ?現(xiàn)在，使用以下命令運(yùn)行 JAR 文件：
java –jar <JARFILE>
? ?應(yīng)用將在?Tomcat 8080 端口啟動(dòng)，如下圖所示：
? ?現(xiàn)在在 POSTMAN 應(yīng)用中輸入以下 URL，可以看到下圖所示的輸出：
? ??GET API URL 為：?http://localhost:8080/products
? ??POST API URL 為：?http://localhost:8080/products
? ??PUT API URL 為：?http://localhost:8080/products/3
? ??DELETE API URL 為：?http://localhost:8080/products/3
