FTP连接java
我正在尝试将文件上传到服务器。 通过FTP将文件上传到服务器的方法是什么？
我写了这堂课：
serverconnect.java：
import java.io.IOException; import java.net.SocketException; import org.apache.commons.net.SocketClient; import org.apache.commons.net.ftp.FTPClient; public class serverconnection { public FTPClient connectftp() { FTPClient ftp = null; try { ftp.connect("ftp://ftp.drivehq.com/"); ftp.login("zule", "*****"); // ftp.changeWorkingDirectory("/public"); // ftp.makeDirectory("200"); } catch (SocketException en) { // TODO Auto-generated catch block en.printStackTrace(); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } return ftp; } } 这是mainActivity（只有相关代码）：
import android.view.View; import android.view.View.OnClickListener; import android.os.Bundle; import android.app.Activity; import android.content.Intent; import android.view.Menu; import android.widget.Button; import android.widget.TextView; import java.io.IOException; import java.net.SocketException; import org.apache.commons.net.ftp.FTPClient; public class MainActivity extends Activity implements OnClickListener { Button scan; String contents; String format; TextView contentstext; TextView formattext; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); //----------------------FTP------------- serverconnection ftpconnect =new serverconnection(); FTPClient ftp=ftpconnect.connectftp(); scan=(Button)findViewById(R.id.scanbutton); .....
当我在手机上安装应用程序时，我收到一个错误：“不幸的是你的应用程序必须停止……”
新代码：
public class MainActivity extends Activity implements OnClickListener { Button scan; String contents; String format; TextView contentstext; TextView formattext; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); //----------------------FTP------------- //serverconnection ftpconnect =new serverconnection(); //SimpleFTP ftp=ftpconnect.connectftp(); SimpleFTP ftp = new SimpleFTP(); try { ftp.connect("market.bugs3.com", 21, "u884282808", "lionetwork1"); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); }
新的logcat：
09-16 13:43:31.131: E/AndroidRuntime(1203): FATAL EXCEPTION: main 09-16 13:43:31.131: E/AndroidRuntime(1203): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.market/com.example.market.MainActivity}: android.os.NetworkOnMainThreadException 09-16 13:43:31.131: E/AndroidRuntime(1203): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1956) 09-16 13:43:31.131: E/AndroidRuntime(1203): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1981) 09-16 13:43:31.131: E/AndroidRuntime(1203): at android.app.ActivityThread.access$600(ActivityThread.java:123) 09-16 13:43:31.131: E/AndroidRuntime(1203): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1147) 09-16 13:43:31.131: E/AndroidRuntime(1203): at android.os.Handler.dispatchMessage(Handler.java:99) 09-16 13:43:31.131: E/AndroidRuntime(1203): at android.os.Looper.loop(Looper.java:137) 09-16 13:43:31.131: E/AndroidRuntime(1203): at android.app.ActivityThread.main(ActivityThread.java:4424) 09-16 13:43:31.131: E/AndroidRuntime(1203): at java.lang.reflect.Method.invokeNative(Native Method) 09-16 13:43:31.131: E/AndroidRuntime(1203): at java.lang.reflect.Method.invoke(Method.java:511) 09-16 13:43:31.131: E/AndroidRuntime(1203): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:784) 09-16 13:43:31.131: E/AndroidRuntime(1203): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:551) 09-16 13:43:31.131: E/AndroidRuntime(1203): at dalvik.system.NativeStart.main(Native Method) 09-16 13:43:31.131: E/AndroidRuntime(1203): Caused by: android.os.NetworkOnMainThreadException 09-16 13:43:31.131: E/AndroidRuntime(1203): at android.os.StrictMode$AndroidBlockGuardPolicy.onNetwork(StrictMode.java:1099) 09-16 13:43:31.131: E/AndroidRuntime(1203): at java.net.InetAddress.lookupHostByName(InetAddress.java:391) 09-16 13:43:31.131: E/AndroidRuntime(1203): at java.net.InetAddress.getAllByNameImpl(InetAddress.java:242) 09-16 13:43:31.131: E/AndroidRuntime(1203): at java.net.InetAddress.getAllByName(InetAddress.java:220) 09-16 13:43:31.131: E/AndroidRuntime(1203): at java.net.Socket.tryAllAddresses(Socket.java:108) 09-16 13:43:31.131: E/AndroidRuntime(1203): at java.net.Socket.(Socket.java:177) 09-16 13:43:31.131: E/AndroidRuntime(1203): at java.net.Socket.(Socket.java:149) 09-16 13:43:31.131: E/AndroidRuntime(1203): at org.jibble.simpleftp.SimpleFTP.connect(SimpleFTP.java:68) 09-16 13:43:31.131: E/AndroidRuntime(1203): at com.example.market.MainActivity.onCreate(MainActivity.java:31) 09-16 13:43:31.131: E/AndroidRuntime(1203): at android.app.Activity.performCreate(Activity.java:4465) 09-16 13:43:31.131: E/AndroidRuntime(1203): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1049) 09-16 13:43:31.131: E/AndroidRuntime(1203): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1920) 09-16 13:43:31.131: E/AndroidRuntime(1203): ... 11 more
问题是你正在尝试在主线程上进行网络调用。 Android 3.0或更高版本不允许使用此function。
您应该通过在不同的线程上调用FTP服务器来解决此问题。 一个好方法是使用AsyncTask：
private class FtpTask extends AsyncTask { protected FTPClient doInBackground(Void... args) { serverconnection ftpconnect =new serverconnection(); FTPClient ftp=ftpconnect.connectftp(); return ftp; } protected void onPostExecute(FTPClient result) { Log.v("FTPTask","FTP connection complete"); ftpClient = result; //Where ftpClient is a instance variable in the main activity } }
然后，您可以使用主线程中的以下代码运行此后台线程：
new FtpTask().execute();
编辑：
如果要在不同方法之间传递参数，可以更改AsyncTask超类初始化。
例如AsyncTask可以将String变量传递给doInBackground方法，使用double跟踪进度并使用整数作为结果类型（结果类型是doInBackground的返回类型，将作为参数发送到onPostExecute）。