Rest模板用于创建使用RESTful Web服务的应用程序。使用exchange()
方法为所有HTTP方法使用Web服务。 下面给出的代码显示了如何创建Rest模板Bean以自动连接Rest模板对象。
package com.zaixian.demo;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.annotation.Bean;
import org.springframework.web.client.RestTemplate;
@SpringBootApplication
public class DemoApplication {
public static void main(String[] args) {
SpringApplication.run(DemoApplication.class, args);
}
@Bean
public RestTemplate getRestTemplate() {
return new RestTemplate();
}
}
GET
通过使用RestTemplate类的exchange()
方法来使用GET API,
假设此URL => http://localhost:8080/products
返回以下JSON,将使用以下代码使用Rest Template来使用此API响应 -
[
{
"id": "1",
"name": "Honey"
},
{
"id": "2",
"name": "Almond"
}
]
必须遵循给定的点来使用API -
- 自动装配Rest模板对象。
- 使用HttpHeaders设置请求标头。
- 使用HttpEntity包装请求对象。
- 为
Exchange()
方法提供URL,HttpMethod和Return类型。
@RestController
public class ConsumeWebService {
@Autowired
RestTemplate restTemplate;
@RequestMapping(value = "/template/products")
public String getProductList() {
HttpHeaders headers = new HttpHeaders();
headers.setAccept(Arrays.asList(MediaType.APPLICATION_JSON));
HttpEntity <String> entity = new HttpEntity<String>(headers);
return restTemplate.exchange("
http://localhost:8080/products", HttpMethod.GET, entity, String.class).getBody();
}
}
POST
通过使用RestTemplate
的exchange()
方法来使用POST API
假设此URL => http://localhost:8080/products
返回如下所示的响应,使用Rest模板测试此API响应。
下面给出的代码是请求正文 -
{
"id":"3",
"name":"Ginger"
}
下面给出的代码是响应内容 -
Product is created successfully
需要遵循以下给出的要点来使用API -
- 自动装配Rest模板对象。
- 使用HttpHeaders设置请求标头。
- 使用HttpEntity包装请求对象。 在这里将
Product
对象包装起来以将其发送到请求主体。
为exchange()
方法提供URL,HttpMethod和Return类型。
@RestController
public class ConsumeWebService {
@Autowired
RestTemplate restTemplate;
@RequestMapping(value = "/template/products", method = RequestMethod.POST)
public String createProducts(@RequestBody Product product) {
HttpHeaders headers = new HttpHeaders();
headers.setAccept(Arrays.asList(MediaType.APPLICATION_JSON));
HttpEntity<Product> entity = new HttpEntity<Product>(product,headers);
return restTemplate.exchange(
"http://localhost:8080/products", HttpMethod.POST, entity, String.class).getBody();
}
}
PUT
通过使用RestTemplate
的exchange()
方法来使用PUT API。
假设此URL=> http://localhost:8080/products/3
返回以下响应,使用RestTemplate
来响应此API。
下面给出的代码是请求主体 -
{
"name":"Huawei"
}
下面给出的代码是响应结果 -
Product is updated successfully
必须遵循以下给出的要点来使用API -
- 自动装配Rest模板对象。
- 使用HttpHeaders设置请求标头。
- 使用HttpEntity包装请求对象。 在这里将Product对象包装起来以将其发送到请求主体。
exchange()
方法提供URL
,HttpMethod
和Return
类型。
@RestController
public class ConsumeWebService {
@Autowired
RestTemplate restTemplate;
@RequestMapping(value = "/template/products/{id}", method = RequestMethod.PUT)
public String updateProduct(@PathVariable("id") String id, @RequestBody Product product) {
HttpHeaders headers = new HttpHeaders();
headers.setAccept(Arrays.asList(MediaType.APPLICATION_JSON));
HttpEntity<Product> entity = new HttpEntity<Product>(product,headers);
return restTemplate.exchange(
"http://localhost:8080/products/"+id, HttpMethod.PUT, entity, String.class).getBody();
}
}
DELETE
通过使用RestTemplate
的 exchange()
方法来使用DELETE API
假设此URL => http://localhost:8080/products/3
返回下面给出的响应,将使用RestTemplate
来使用此API响应。
下面显示的这行代码是响应正文 -
Product is deleted successfully
必须按照下面显示的点来使用API -
- 自动装配Rest模板对象。
- 使用HttpHeaders设置请求标头。
- 使用HttpEntity包装请求对象。
为exchange()
方法提供URL,HttpMethod和Return类型。
@RestController
public class ConsumeWebService {
@Autowired
RestTemplate restTemplate;
@RequestMapping(value = "/template/products/{id}", method = RequestMethod.DELETE)
public String deleteProduct(@PathVariable("id") String id) {
HttpHeaders headers = new HttpHeaders();
headers.setAccept(Arrays.asList(MediaType.APPLICATION_JSON));
HttpEntity<Product> entity = new HttpEntity<Product>(headers);
return restTemplate.exchange(
"http://localhost:8080/products/"+id, HttpMethod.DELETE, entity, String.class).getBody();
}
}
完整的Rest Template控制器类文件如下 -
package com.zaixian.demo.controller;
import java.util.Arrays;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.http.HttpEntity;
import org.springframework.http.HttpHeaders;
import org.springframework.http.HttpMethod;
import org.springframework.http.MediaType;
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 org.springframework.web.client.RestTemplate;
import com.zaixian.demo.model.Product;
@RestController
public class ConsumeWebService {
@Autowired
RestTemplate restTemplate;
@RequestMapping(value = "/template/products")
public String getProductList() {
HttpHeaders headers = new HttpHeaders();
headers.setAccept(Arrays.asList(MediaType.APPLICATION_JSON));
HttpEntity<String> entity = new HttpEntity<String>(headers);
return restTemplate.exchange(
"http://localhost:8080/products", HttpMethod.GET, entity, String.class).getBody();
}
@RequestMapping(value = "/template/products", method = RequestMethod.POST)
public String createProducts(@RequestBody Product product) {
HttpHeaders headers = new HttpHeaders();
headers.setAccept(Arrays.asList(MediaType.APPLICATION_JSON));
HttpEntity<Product> entity = new HttpEntity<Product>(product,headers);
return restTemplate.exchange(
"http://localhost:8080/products", HttpMethod.POST, entity, String.class).getBody();
}
@RequestMapping(value = "/template/products/{id}", method = RequestMethod.PUT)
public String updateProduct(@PathVariable("id") String id, @RequestBody Product product) {
HttpHeaders headers = new HttpHeaders();
headers.setAccept(Arrays.asList(MediaType.APPLICATION_JSON));
HttpEntity<Product> entity = new HttpEntity<Product>(product,headers);
return restTemplate.exchange(
"http://localhost:8080/products/"+id, HttpMethod.PUT, entity, String.class).getBody();
}
@RequestMapping(value = "/template/products/{id}", method = RequestMethod.DELETE)
public String deleteProduct(@PathVariable("id") String id) {
HttpHeaders headers = new HttpHeaders();
headers.setAccept(Arrays.asList(MediaType.APPLICATION_JSON));
HttpEntity<Product> entity = new HttpEntity<Product>(headers);
return restTemplate.exchange(
"http://localhost:8080/products/"+id, HttpMethod.DELETE, entity, String.class).getBody();
}
}
Spring Boot应用程序类 - DemoApplication.java 的代码如下 -
package com.zaixian.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构建文件- pom.xml 的代码如下 -
<?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.zaixian</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构建文件 - build.gradle 的代码如下 -
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.zaixian'
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')
}
创建可执行的JAR文件,并使用以下Maven或Gradle命令运行Spring Boot应用程序:
对于Maven,使用下面给出的命令 -
mvn clean install
在“BUILD SUCCESS”之后,可以在target
目录下找到JAR文件。
对于Gradle,使用下面显示的命令 -
gradle clean build
在“BUILD SUCCESSFUL”之后,可以在build/libs 目录下找到JAR文件。
现在,使用以下命令运行JAR文件 -
java –jar <JARFILE>
现在,应用程序已在Tomcat端口8080上启动。
现在点击POSTMAN 应用程序中的以下URL,可以看到输出。
通过Rest模板获取产品 - http://localhost:8080/template/products
创建产品POST - http://localhost:8080/template/products
更新产品PUT - http://localhost:8080/template/products/3
删除产品 DELETE - http://localhost:8080/template/products/3