Java網絡訪問 java調用http java調用其他接口

通過SpringBoot-RestTemplate

• delete() 在特定的URL上對資源執行HTTP DELETE操作
• exchange() 在URL上執行特定的HTTP方法，返回包含對象的ResponseEntity，這個對象是從響應體中映射得到的
• execute() 在URL上執行特定的HTTP方法，返回一個從響應體映射得到的對象
• getForEntity() 發送一個HTTP GET請求，返回的ResponseEntity包含了響應體所映射成的對象
• getForObject() 發送一個HTTP GET請求，返回的請求體將映射為一個對象
• postForEntity() POST 數據到一個URL，返回包含一個對象的ResponseEntity，這個對象是從響應體中映射得到的
• postForObject() POST 數據到一個URL，返回根據響應體匹配形成的對象
• headForHeaders() 發送HTTP HEAD請求，返回包含特定資源URL的HTTP頭
• optionsForAllow() 發送HTTP OPTIONS請求，返回對特定URL的Allow頭信息
• postForLocation() POST 數據到一個URL，返回新創建資源的URL
• put() PUT 資源到特定的URL

導入springboot的web包

<parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.0.4.RELEASE</version>
    </parent>

    <dependencies>
        <!--CloseableHttpClient-->
        <dependency>
            <groupId>org.apache.httpcomponents</groupId>
            <artifactId>httpclient</artifactId>
            <version>4.5.2</version>
        </dependency>

        <!--spring restTemplate-->
        <!-- @ConfigurationProperties annotation processing (metadata for IDEs)
                生成spring-configuration-metadata.json類，需要引入此類-->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-configuration-processor</artifactId>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-aop</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
            <exclusions>
                <exclusion>
                    <groupId>org.springframework.boot</groupId>
                    <artifactId>spring-boot-starter-tomcat</artifactId>
                </exclusion>
            </exclusions>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-jetty</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
    </dependencies>

在啟動類同包下創建RestTemplateConfig.java類

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.http.client.ClientHttpRequestFactory;
import org.springframework.http.client.SimpleClientHttpRequestFactory;
import org.springframework.web.client.RestTemplate;


@Configuration
public class RestTemplateConfig {

    @Bean
    public RestTemplate restTemplate(ClientHttpRequestFactory factory){
        return new RestTemplate(factory);
    }

    @Bean
    public ClientHttpRequestFactory simpleClientHttpRequestFactory(){
        SimpleClientHttpRequestFactory factory = new SimpleClientHttpRequestFactory();
        factory.setConnectTimeout(15000);
        factory.setReadTimeout(5000);
        return factory;
    }
}

然后在Service類（RestTemplateToInterface ）中注入使用

import com.alibaba.fastjson.JSONObject;
import com.swordfall.model.User;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.http.*;
import org.springframework.stereotype.Service;
import org.springframework.web.client.RestTemplate;

@Service
public class RestTemplateToInterface {

    @Autowired
    private RestTemplate restTemplate;

    /**
     * 以get方式請求第三方http接口 getForEntity
     * @param url
     * @return
     */
    public User doGetWith1(String url){
        ResponseEntity<User> responseEntity = restTemplate.getForEntity(url, User.class);
        User user = responseEntity.getBody();
        return user;
    }

    /**
     * 以get方式請求第三方http接口 getForObject
     * 返回值返回的是響應體，省去了我們再去getBody()
     * @param url
     * @return
     */
    public User doGetWith2(String url){
        User user  = restTemplate.getForObject(url, User.class);
        return user;
    }

    /**
     * 以post方式請求第三方http接口 postForEntity
     * @param url
     * @return
     */
    public String doPostWith1(String url){
        User user = new User("小白", 20);
        ResponseEntity<String> responseEntity = restTemplate.postForEntity(url, user, String.class);
        String body = responseEntity.getBody();
        return body;
    }

    /**
     * 以post方式請求第三方http接口 postForEntity
     * @param url
     * @return
     */
    public String doPostWith2(String url){
        User user = new User("小白", 20);
        String body = restTemplate.postForObject(url, user, String.class);
        return body;
    }

    /**
     * exchange
     * @return
     */
    public String doExchange(String url, Integer age, String name){
        //header參數
        HttpHeaders headers = new HttpHeaders();
        String token = "asdfaf2322";
        headers.add("authorization", token);
        headers.setContentType(MediaType.APPLICATION_JSON);

        //放入body中的json參數
        JSONObject obj = new JSONObject();
        obj.put("age", age);
        obj.put("name", name);

        //組裝
        HttpEntity<JSONObject> request = new HttpEntity<>(obj, headers);
        ResponseEntity<String> responseEntity = restTemplate.exchange(url, HttpMethod.POST, request, String.class);
        String body = responseEntity.getBody();
        return body;
    }
}