Android APP使用HTTP访问WEB服务,在接收数据时发生错误,提示
java.net.SocketException: Permission denied
- 1
之前一直无法连接原因为:没加
<uses-permission android:name="android.permission.INTERNET" />
先来张效果图:
使用Socket扫描端口的几个步骤:
1,先开启一个异步线程。
2,在异步线程里声明套接字(Socket).
3,将套接字与指定ip服务器的指定端口连接。
4,连接成功即为该端口可用。
*******记得在Manifests里加网络权限,不然就无法连接QWQ
像这样子:
java.net.SocketException: Permission denied
package com.example.zzk.socketdeom;
import android.annotation.SuppressLint;
import android.os.Handler;
import android.os.Message;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
import java.io.IOException;
import java.net.InetSocketAddress;
import java.net.Socket;
import java.net.SocketAddress;
public class MainActivity extends AppCompatActivity {
Button btn;
TextView text;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
btn=findViewById(R.id.st_btn);
text=findViewById(R.id.textview);
btn.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
scanPorts();
}
});
}
public void scanPorts(){
new ScanPorts(0,200).start();
}
class ScanPorts extends Thread{
private int _min;
private int _max;
public ScanPorts(int _min,int _max){
this._min=_min;
this._max=_max;
}
@Override
public void run() {
for(int i=_min;i<_max;i++){
Socket socket=new Socket();
SocketAddress socketAddress=new InetSocketAddress("169.254.76.42",i);
try {
socket.connect(socketAddress,50);
handler.sendEmptyMessage(i);
socket.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
@SuppressLint("HandlerLeak")
private Handler handler=new Handler(){
@Override
public void handleMessage(Message msg) {
text.append(String.valueOf(msg.what)+":ok\n");
super.handleMessage(msg);
}
};
}