我正在尝试为自己实现一个小的Android应用程序，它应该从我的Android设备上传文件到ftp服务器。 虽然我努力了，但我无法弄清楚问题出在哪里。
TIA，Lizzie
这是我的主要功能（我试过各种服务器IP ......）：
package com.uploadtonas_03;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import org.apache.commons.net.ftp.FTPClient;
import org.apache.commons.net.ftp.FTPReply;
public class MainActivity extends AppCompatActivity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
String server = "****";
int port = 21;
String user = "***";
String pass = "***";
FTPClient ftpClient = new FTPClient();
try {
ftpClient.connect(server, port);
ftpClient.enterLocalPassiveMode(); // important!
showServerReply(ftpClient);
int replyCode = ftpClient.getReplyCode();
if (!FTPReply.isPositiveCompletion(replyCode)) {
System.out.println("Operation failed. Server reply code: " + replyCode);
return;
}
boolean success = ftpClient.login(user, pass);
showServerReply(ftpClient);
if (!success) {
System.out.println("Could not login to the server");
return;
} else {
System.out.println("LOGGED IN SERVER");
}
} catch (java.io.IOException ex) {
System.out.println("Oops! Something wrong happened");
ex.printStackTrace();
}
}
private static void showServerReply(FTPClient ftpClient) {
String[] replies = ftpClient.getReplyStrings();
if (replies != null && replies.length > 0) {
for (String aReply : replies) {
System.out.println("SERVER: " + aReply);
我在manifest.xml中添加了相应的权限
<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
并收到以下错误：
08-07 14:39:07.230 31520-31520/com.uploadtonas_03 E/AndroidRuntime: FATAL EXCEPTION: main
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.uploadtonas_03/com.uploadtonas_03.MainActivity}: android.os.NetworkOnMainThreadException
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2250)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2300)
at android.app.ActivityThread.access$600(ActivityThread.java:144)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1295)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:150)
at android.app.ActivityThread.main(ActivityThread.java:5162)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:525)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:744)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:560)
at dalvik.system.NativeStart.main(Native Method)
Caused by: android.os.NetworkOnMainThreadException
at android.os.StrictMode$AndroidBlockGuardPolicy.onNetwork(StrictMode.java:1133)
at java.net.InetAddress.lookupHostByName(InetAddress.java:385)
at java.net.InetAddress.getAllByNameImpl(InetAddress.java:236)
at java.net.InetAddress.getByName(InetAddress.java:289)
at org.apache.commons.net.SocketClient.connect(SocketClient.java:209)
at com.uploadtonas_03.MainActivity.onCreate(MainActivity.java:24)
at android.app.Activity.performCreate(Activity.java:5133)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1087)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2214)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2300)
at android.app.ActivityThread.access$600(ActivityThread.java:144)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1295)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:150)
at android.app.ActivityThread.main(ActivityThread.java:5162)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:525)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:744)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:560)
at dalvik.system.NativeStart.main(Native Method)