用java+testng框架写一个自动化接口测试的代码

下面是一个使用Java和TestNG框架编写的自动化接口测试的示例代码：

import org.testng.annotations.Test;
import io.restassured.RestAssured;
import io.restassured.response.Response;
import io.restassured.specification.RequestSpecification;
import static org.testng.Assert.assertEquals;

public class ApiTest {

    @Test
    public void testGetRequest() {
        RestAssured.baseURI = "https://jsonplaceholder.typicode.com";
        RequestSpecification request = RestAssured.given();
        Response response = request.get("/users");
        int statusCode = response.getStatusCode();
        assertEquals(statusCode, 200);
        String responseBody = response.getBody().asString();
        System.out.println(responseBody);
    }

    @Test
    public void testPostRequest() {
        RestAssured.baseURI = "https://jsonplaceholder.typicode.com";
        RequestSpecification request = RestAssured.given();
        request.header("Content-Type", "application/json");
        String requestBody = "{\"title\": \"foo\", \"body\": \"bar\", \"userId\": 1}";
        request.body(requestBody);
        Response response = request.post("/posts");
        int statusCode = response.getStatusCode();
        assertEquals(statusCode, 201);
        String responseBody = response.getBody().asString();
        System.out.println(responseBody);
    }

    @Test
    public void testPutRequest() {
        RestAssured.baseURI = "https://jsonplaceholder.typicode.com";
        RequestSpecification request = RestAssured.given();
        request.header("Content-Type", "application/json");
        String requestBody = "{\"title\": \"foo\", \"body\": \"bar\", \"userId\": 1}";
        request.body(requestBody);
        Response response = request.put("/posts/1");
        int statusCode = response.getStatusCode();
        assertEquals(statusCode, 200);
        String responseBody = response.getBody().asString();
        System.out.println(responseBody);
    }

    @Test
    public void testDeleteRequest() {
        RestAssured.baseURI = "https://jsonplaceholder.typicode.com";
        RequestSpecification request = RestAssured.given();
        Response response = request.delete("/posts/1");
        int statusCode = response.getStatusCode();
        assertEquals(statusCode, 200);
        String responseBody = response.getBody().asString();
        System.out.println(responseBody);
    }
}

在上面的代码中，我们使用了RestAssured库来发送HTTP请求，并使用TestNG断言来验证响应。我们编写了四个测试用例，分别测试了GET、POST、PUT和DELETE请求。在每个测试用例中，我们都设置了请求的URL、头部、请求体，并发送请求。然后，我们验证响应的状态码和响应体，并将响应体打印到控制台中。