用php下载android的大文件

Question

大家好我想创建从数据库服务器下载文件的android应用程序， 我找到了很多像这样的例子：

    import java.io.BufferedInputStream;
import java.io.DataOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URISyntaxException;
import java.net.URL;

public class fileUploadDownload {

    /**
     * @param args
     * @throws URISyntaxException 
     * @throws IOException 
     */
    public static void main(String[] args) throws IOException, URISyntaxException {

        uploadFileToServer("video.mp4","http://upload.php");
        downloadFileFromServer("video.mp4","http://video.mp4");
    }

    /**
     * This function upload the large file to server with other POST values.
     * @param filename
     * @param targetUrl
     * @return
     */
    public static String uploadFileToServer(String filename, String targetUrl) {
        String response = "error";
        HttpURLConnection connection = null;
        DataOutputStream outputStream = null;

        String pathToOurFile = filename;
        String urlServer = targetUrl;
        String lineEnd = "\r\n";
        String twoHyphens = "--";
        String boundary = "*****";

        int bytesRead, bytesAvailable, bufferSize;
        byte[] buffer;
        int maxBufferSize = 1 * 1024;
        try {
            FileInputStream fileInputStream = new FileInputStream(new File(
                    pathToOurFile));

            URL url = new URL(urlServer);
            connection = (HttpURLConnection) url.openConnection();

            // Allow Inputs & Outputs
            connection.setDoInput(true);
            connection.setDoOutput(true);
            connection.setUseCaches(false);
            connection.setChunkedStreamingMode(1024);
            // Enable POST method
            connection.setRequestMethod("POST");

            connection.setRequestProperty("Connection", "Keep-Alive");
            connection.setRequestProperty("Content-Type",
                    "multipart/form-data; boundary=" + boundary);

            outputStream = new DataOutputStream(connection.getOutputStream());
            outputStream.writeBytes(twoHyphens + boundary + lineEnd);

            String token = "anyvalye";
            outputStream.writeBytes("Content-Disposition: form-data; name=\"Token\"" + lineEnd);
            outputStream.writeBytes("Content-Type: text/plain;charset=UTF-8" + lineEnd);
            outputStream.writeBytes("Content-Length: " + token.length() + lineEnd);
            outputStream.writeBytes(lineEnd);
            outputStream.writeBytes(token + lineEnd);
            outputStream.writeBytes(twoHyphens + boundary + lineEnd);

            String taskId = "anyvalue";
            outputStream.writeBytes("Content-Disposition: form-data; name=\"TaskID\"" + lineEnd);
            outputStream.writeBytes("Content-Type: text/plain;charset=UTF-8" + lineEnd);
            outputStream.writeBytes("Content-Length: " + taskId.length() + lineEnd);
            outputStream.writeBytes(lineEnd);
            outputStream.writeBytes(taskId + lineEnd);
            outputStream.writeBytes(twoHyphens + boundary + lineEnd);

            String connstr = null;
            connstr = "Content-Disposition: form-data; name=\"UploadFile\";filename=\""
                    + pathToOurFile + "\"" + lineEnd;

            outputStream.writeBytes(connstr);
            outputStream.writeBytes(lineEnd);

            bytesAvailable = fileInputStream.available();
            bufferSize = Math.min(bytesAvailable, maxBufferSize);
            buffer = new byte[bufferSize];

            // Read file
            bytesRead = fileInputStream.read(buffer, 0, bufferSize);
            System.out.println("Image length " + bytesAvailable + "");
            try {
                while (bytesRead > 0) {
                    try {
                        outputStream.write(buffer, 0, bufferSize);
                    } catch (OutOfMemoryError e) {
                        e.printStackTrace();
                        response = "outofmemoryerror";
                        return response;
                    }
                    bytesAvailable = fileInputStream.available();
                    bufferSize = Math.min(bytesAvailable, maxBufferSize);
                    bytesRead = fileInputStream.read(buffer, 0, bufferSize);
                }
            } catch (Exception e) {
                e.printStackTrace();
                response = "error";
                return response;
            }
            outputStream.writeBytes(lineEnd);
            outputStream.writeBytes(twoHyphens + boundary + twoHyphens
                    + lineEnd);

            // Responses from the server (code and message)
            int serverResponseCode = connection.getResponseCode();
            String serverResponseMessage = connection.getResponseMessage();
            System.out.println("Server Response Code " + " " + serverResponseCode);
            System.out.println("Server Response Message "+ serverResponseMessage);

            if (serverResponseCode == 200) {
                response = "true";
            }else
            {
                response = "false";
            }

            fileInputStream.close();
            outputStream.flush();

            connection.getInputStream();
            //for android InputStream is = connection.getInputStream();
            java.io.InputStream is = connection.getInputStream();

            int ch;
            StringBuffer b = new StringBuffer();
            while( ( ch = is.read() ) != -1 ){
                b.append( (char)ch );
            }

            String responseString = b.toString();
            System.out.println("response string is" + responseString); //Here is the actual output

            outputStream.close();
            outputStream = null;

        } catch (Exception ex) {
            // Exception handling
            response = "error";
            System.out.println("Send file Exception" + ex.getMessage() + "");
            ex.printStackTrace();
        }
        return response;
    }

    /**
     * This function download the large files from the server
     * @param filename
     * @param urlString
     * @throws MalformedURLException
     * @throws IOException
     */
    public static void downloadFileFromServer(String filename, String urlString) throws MalformedURLException, IOException
    {
        BufferedInputStream in = null;
        FileOutputStream fout = null;
        try
        {
            URL url = new URL(urlString);

            in = new BufferedInputStream(url.openStream());
            fout = new FileOutputStream(filename);

            byte data[] = new byte[1024];
            int count;
            while ((count = in.read(data, 0, 1024)) != -1)
            {
                fout.write(data, 0, count);
                System.out.println(count);
            }
        }
        finally
        {
            if (in != null)
                    in.close();
            if (fout != null)
                    fout.close();
        }
        System.out.println("Done");
    }
}

但我无法理解如何通过php连接服务器，我的意思是当我想将其更改为链接时的链接路径将我带到服务器中的php文件，这有助于完成从中下载文件的过程数据库，我发现的所有示例都包含没有php的java部分 如果您有任何需要我感谢的例子，请帮助我。