如何使用php和volley android进行间接文件下载

<?php
$fileUrl = $_GET['url']; // 从请求参数中获取文件的URL
$fileName = basename($fileUrl); // 获取文件名

header("Content-Type: application/octet-stream");
header("Content-Disposition: attachment; filename=\"$fileName\"");
echo file_get_contents($fileUrl);
?>

dependencies {
    implementation 'com.android.volley:volley:1.2.1'
}

import com.android.volley.Request;
import com.android.volley.Response;
import com.android.volley.VolleyError;
import com.android.volley.toolbox.StringRequest;
import com.android.volley.toolbox.Volley;

import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;

public class FileDownloader {
    public static void downloadFile(String fileUrl, String savePath, final OnDownloadListener listener) {
        StringRequest request = new StringRequest(Request.Method.GET, fileUrl,
                new Response.Listener<String>() {
                    @Override
                    public void onResponse(String response) {
                        try {
                            // 将服务器返回的文件内容保存到本地存储
                            FileOutputStream outputStream = new FileOutputStream(savePath);
                            outputStream.write(response.getBytes());
                            outputStream.close();
                            listener.onDownloadComplete();
                        } catch (IOException e) {
                            e.printStackTrace();
                            listener.onDownloadError(e.getMessage());
                        }
                    }
                },
                new Response.ErrorListener() {
                    @Override
                    public void onErrorResponse(VolleyError error) {
                        listener.onDownloadError(error.getMessage());
                    }
                });

        // 发送请求
        Volley.newRequestQueue(context).add(request);
    }

    public interface OnDownloadListener {
        void onDownloadComplete();
        void onDownloadError(String error);
    }
}

String fileUrl = "http://example.com/file.pdf";
String savePath = "/sdcard/download/file.pdf";

FileDownloader.downloadFile(fileUrl, savePath, new FileDownloader.OnDownloadListener() {
    @Override
    public void onDownloadComplete() {
        // 文件下载完成后的处理逻辑
    }

    @Override
    public void onDownloadError(String error) {
        // 文件下载出错时的处理逻辑
    }
});