Android HttpClient操作

1. HttpClient简介

HttpClient是一个开源的HTTP协议客户端库，用于发送HTTP请求和接收HTTP响应。它可以用于Android平台上与服务器进行通信的各种应用场景，如发送POST请求、GET请求、文件上传、文件下载等。

2. 导入HttpClient库

在项目的build.gradle文件中添加以下依赖项：

dependencies {
    implementation 'org.apache.httpcomponents:httpclient:4.5.13'
}

3. 使用HttpClient发送GET请求

下面是一个使用HttpClient发送GET请求的示例代码：

import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.HttpResponse;
import org.apache.http.StatusLine;
import org.apache.http.util.EntityUtils;

public class HttpUtils {
    public static String sendGETRequest(String url) {
        String response = null;
        try {
            HttpClient httpClient = new DefaultHttpClient();
            HttpGet httpGet = new HttpGet(url);
            HttpResponse httpResponse = httpClient.execute(httpGet);
            StatusLine statusLine = httpResponse.getStatusLine();
            if (statusLine.getStatusCode() == 200) {
                response = EntityUtils.toString(httpResponse.getEntity());
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
        return response;
    }
}

4. 使用HttpClient发送POST请求

下面是一个使用HttpClient发送POST请求的示例代码：

import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.entity.StringEntity;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.HttpResponse;
import org.apache.http.StatusLine;
import org.apache.http.util.EntityUtils;

public class HttpUtils {
    public static String sendPOSTRequest(String url, String data) {
        String response = null;
        try {
            HttpClient httpClient = new DefaultHttpClient();
            HttpPost httpPost = new HttpPost(url);
            StringEntity stringEntity = new StringEntity(data);
            httpPost.setEntity(stringEntity);
            httpPost.setHeader("Content-Type", "application/json");
            HttpResponse httpResponse = httpClient.execute(httpPost);
            StatusLine statusLine = httpResponse.getStatusLine();
            if (statusLine.getStatusCode() == 200) {
                response = EntityUtils.toString(httpResponse.getEntity());
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
        return response;
    }
}

5. 注意事项

• HttpClient已被Android官方废弃，推荐使用HttpURLConnection或OkHttp替代。
• 在Android 9.0及以上版本中，需要在AndroidManifest.xml文件中添加以下配置项以支持使用HttpClient：

<uses-library android:name="org.apache.http.legacy" android:required="false" />

6. 总结

通过HttpClient库，我们可以方便地在Android应用中与服务器进行HTTP通信。然而，由于HttpClient已被废弃，并且存在一些性能和安全性问题，建议使用更现代的HTTP客户端库。

本文来自极简博客，作者：星空下的约定，转载请注明原文链接：Android HttpClient操作