java httpclient 接口_Java利用httpclient通过get、post方式调用https接口的方法

Java中可以使用Apache HttpClient库来发送HTTP请求，包括GET、POST等方式，也可以通过HttpClient库发送HTTPS请求。使用HttpClient发送HTTPS请求需要添加SSL证书和设置SSL连接的相关参数。

以下是通过HttpClient库发送GET、POST请求的示例代码：

1. 发送GET请求

import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.util.EntityUtils;

public class HttpClientTest {

    public static void main(String[] args) throws Exception {
        CloseableHttpClient httpClient = HttpClients.createDefault();
        String url = "http://www.example.com/api?param1=value1&param2=value2";
        HttpGet httpGet = new HttpGet(url);
        String response = null;
        try (CloseableHttpResponse httpResponse = httpClient.execute(httpGet)) {
            response = EntityUtils.toString(httpResponse.getEntity());
        }
        System.out.println(response);
    }

}

2. 发送POST请求

import org.apache.http.client.methods.HttpPost;
import org.apache.http.entity.StringEntity;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.util.EntityUtils;

public class HttpClientTest {

    public static void main(String[] args) throws Exception {
        CloseableHttpClient httpClient = HttpClients.createDefault();
        String url = "http://www.example.com/api";
        HttpPost httpPost = new HttpPost(url);
        httpPost.setHeader("Content-Type", "application/json;charset=UTF-8");
        String requestBody = "{\"param1\":\"value1\",\"param2\":\"value2\"}";
        httpPost.setEntity(new StringEntity(requestBody, "UTF-8"));
        String response = null;
        try (CloseableHttpResponse httpResponse = httpClient.execute(httpPost)) {
            response = EntityUtils.toString(httpResponse.getEntity());
        }
        System.out.println(response);
    }

}

如果需要发送HTTPS请求，则需要添加SSL证书和设置SSL连接的相关参数。具体可以参考以下示例代码：

import org.apache.http.client.config.RequestConfig;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.config.Registry;
import org.apache.http.config.RegistryBuilder;
import org.apache.http.conn.socket.ConnectionSocketFactory;
import org.apache.http.conn.socket.PlainConnectionSocketFactory;
import org.apache.http.conn.ssl.SSLConnectionSocketFactory;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.impl.conn.PoolingHttpClientConnectionManager;
import org.apache.http.ssl.SSLContexts;
import org.apache.http.ssl.TrustStrategy;
import org.apache.http.util.EntityUtils;

import javax.net.ssl.HostnameVerifier;
import javax.net.ssl.SSLContext;
import javax.net.ssl.SSLSession;
import java.security.cert.CertificateException;
import java.security.cert.X509Certificate;

public class HttpClientTest {

    public static void main(String[] args) throws Exception {
        SSLContext sslContext = SSLContexts.custom()
                .loadTrustMaterial(null, new TrustStrategy() {
                    @Override
                    public boolean isTrusted(X509Certificate[] chain, String authType) throws CertificateException {
                        return true;
                    }
                }).build();
        HostnameVerifier hostnameVerifier = new HostnameVerifier() {
            @Override
            public boolean verify(String hostname, SSLSession session) {
                return true;
            }
        };
        SSLConnectionSocketFactory sslSocketFactory = new SSLConnectionSocketFactory(sslContext, hostnameVerifier);
        Registry<ConnectionSocketFactory> socketFactoryRegistry = RegistryBuilder.<ConnectionSocketFactory>create()
                .register("https", sslSocketFactory)
                .register("http", new PlainConnectionSocketFactory())
                .build();
        PoolingHttpClientConnectionManager connectionManager = new PoolingHttpClientConnectionManager(socketFactoryRegistry);
        connectionManager.setMaxTotal(200);
        connectionManager.setDefaultMaxPerRoute(20);
        RequestConfig requestConfig = RequestConfig.custom()
                .setSocketTimeout(5000)
                .setConnectTimeout(5000)
                .setConnectionRequestTimeout(5000)
                .build();
        CloseableHttpClient httpClient = HttpClients.custom()
                .setConnectionManager(connectionManager)
                .setDefaultRequestConfig(requestConfig)
                .build();
        String url = "https://www.example.com/api?param1=value1&param2=value2";
        HttpGet httpGet = new HttpGet(url);
        String response = null;
        try (CloseableHttpResponse httpResponse = httpClient.execute(httpGet)) {
            response = EntityUtils.toString(httpResponse.getEntity());
        }
        System.out.println(response);
    }

}

需要注意的是，以上代码中的SSL证书验证方式为信任所有证书，不建议在生产环境中使用。建议根据实际情况设置合适的证书验证方式。