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GitHub地址：https://github.com/abel-max/Java-Study-Note/tree/master
服務組件是包含 @Service 註解的類文件。這些類文件可用在與 @RestController 類文件所不同的層來編寫業務邏輯。創建服務組件類文件如下所示：
public interface ProductService {
}
以 @Service 註解實現接口的類如下所示：
@Service
public class ProductServiceImpl implements ProductService {
}
回顧以前的教程中，我們使用產品服務 API(s) 來存儲、獲取、更新和刪除產品。我們在 @RestController 類文件自身中編寫業務邏輯。現在我們要把業務邏輯代碼從控制器移到服務組件。
你可以創建一個接口，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();
}
以下代碼將讓你創建一個以 @Service 註解來實現 ProductService 接口的類，用以編寫存儲、獲取、刪除和更新產品。
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();
}}
以裏的代碼展示了 Rest Controller 類文件，我們用 @Autowired 來自動注入 ProductService 接口並調用其方法。
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')
}
現在你可以使用 Maven 或 Gradle 命令創建可執行 executable JAR 文件並運行 Spring Boot 應用了：
Maven 命令如下：
mvn clean install
在 “BUILD SUCCESS” 之後，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” 之後，你可以在 build/libs 目錄下找到 JAR 文件。
現在，使用以下命令運行 JAR 文件：
java –jar <JARFILE>
應用將在 Tomcat 8080 端口啓動，如下圖所示：
現在在 POSTMAN 應用中輸入以下 URL，可以看到下圖所示的輸出：
GET API URL 爲：
POST API URL 爲：
PUT API URL 爲：
DELETE API URL 爲：