我正在编写一段代码,需要每秒将数据从Android手机发送到桌面电脑(Linux服务器)。由于数据发送非常频繁,因此无法通过Http请求实现(因为它会消耗时间),Tcp通信似乎是更好的选择,因为可以通过这种套接字编程非常快速地发送来自Android手机的数据。
Android手机上的客户端代码如下:
import java.io.IOException;
import java.io.OutputStream;
import java.io.PrintWriter;
import java.net.InetAddress;
import java.net.Socket;
import java.net.UnknownHostException;
import android.app.Activity;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
public class GetWebPage extends Activity {
//Handler h;
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
final EditText eText = (EditText) findViewById(R.id.address);
final TextView tView = (TextView) findViewById(R.id.pagetext);
final Button button = (Button) findViewById(R.id.ButtonGo);
button.setOnClickListener(new Button.OnClickListener() {
public void onClick(View v) {
try {
Log.v("Tcp","Clicked the button");
InetAddress serveraddress=InetAddress.getByName("67.23.14.156");
Log.v("Tcp", "Got the InetAddress");
Socket s = new Socket(serveraddress,4447);
Log.v("Tcp","Got the Socket address");
OutputStream out = s.getOutputStream();
PrintWriter output = new PrintWriter(out);
output.println("Hello Android!");
out.close();
} catch (UnknownHostException e) {
tView.setText(e.toString());
Log.v("Tcp",e.toString());
} catch (IOException e) {
tView.setText(e.toString());
Log.v("Tcp",e.toString());
}catch (Exception e) {
tView.setText(e.toString());
}
}
});
}
}
服务器端的代码如下:
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.ServerSocket;
import java.net.Socket;
public class ListenIncomingTcpConnection {
public static void main(String[] args) {
ServerSocket serverSocket=null;
Socket client=null;
try {
System.out.println("Creating the server object...");
serverSocket = new ServerSocket(4447);
System.out.println("Waiting for the connection...");
} catch (IOException e1) {
System.out.println(e1);
}
while (true) {
try {
client = serverSocket.accept();
System.out.println("Reading the content...");
} catch (IOException e1) {
System.out.println(e1);
e1.printStackTrace();
}
try {
BufferedReader in = new BufferedReader(new InputStreamReader(client.getInputStream()));
String str = in.readLine();
System.out.println("Reading the content.....");
} catch(Exception e) {
System.out.println(e);
} finally {
try{
client.close();
}catch(Exception e){
System.out.println(e);
}
}
}//while
}//PSVM
}
清单文件的代码如下:
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.spce" android:versionCode="1" android:versionName="1.0">
<uses-sdk android:minSdkVersion="4" />
<application android:icon="@drawable/icon" android:label="@string/app_name">
<activity android:name="GetWebPage">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
<uses-permission android:name="android.permission.INTERNET"></uses-permission>
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"></uses-permission>
<uses-permission android:name="android.permission.ACCESS_WIFI_STATE"></uses-permission>
</manifest>
我已经通过putty在Linux机器上使用“java”命令执行了服务器代码。它执行并停留在此行“client = serverSocket.accept();” 当我在Android手机上执行客户端时,它会显示:
点击按钮 获取InetAddress java.net.SocketException:无法连接到主机
我无法确定无法连接到主机的原因。
请帮助解决这个问题。