我有一个运行的java服务器和一个连接它的android客户端。我可以成功发送和接收来自第一个Android活动的数据。
我想要做的是，当我点击我的登录按钮（有效）时，我想关闭一个活动（主页）中的连接，停止服务器，重新启动服务器并打开一个新连接重定向页面。
当我关闭客户端的连接（并重新启动服务器）并在下一页重新启动客户端时，某些东西必定是错误的，因为我的服务器重新启动，但第二个android活动启动并连接到服务器，但从不接受或接收I / O流。我从来没有得到I / O流的确认。
可能是我在服务器中只创建一次套接字??
服务器
public static void main(String[] args)
{
SASSServer s = new SASSServer();
}
public SASSServer()
{
try {
BuildUI();
setTitle("SASS Server");
pack();
setVisible(true);
} catch (IOException ex) {
Logger.getLogger(SASSServer.class.getName()).log(Level.SEVERE, null, ex);
}
}
public void BuildUI() throws IOException
{
// create keypad
JPanel p = new JPanel();
/*
enterField = new JTextField();
enterField.setEnabled(true);
enterField.addActionListener(
new ActionListener() {
// send message to client
public void actionPerformed(ActionEvent event) {
sendData(event.getActionCommand());
}
}
);
p.add(enterField);*/
p.setLayout(new GridLayout(4, 1, 2, 2));
ConnectServer = new JButton("Connect to server");
p.add(ConnectServer);
ConnectDatabase = new JButton("Connect to database");
p.add(ConnectDatabase);
CloseServer = new JButton("Close Server");
p.add(CloseServer);
add("Center", p);
addWindowListener(this);
addWindowFocusListener(this);
addWindowStateListener(this);
ConnectServer.addActionListener(this);
ConnectDatabase.addActionListener(this);
CloseServer.addActionListener(this);
Create a ServerSocket.
server = new ServerSocket(5001, 100);
}
public void runServer() throws Exception
{
try
{
while (true) {
// Step 2: Wait for a connection.
waitForConnection();
// Step 3: Get input and output streams.
getStreams();
// Step 4: Process connection.
processConnections();
// Step 5: Close connection.
closeConnection();
++counter;
}
}
catch (EOFException eofException)
{
System.out.println("Client terminated connection");
} catch (IOException ioException) {
ioException.printStackTrace();
}
}
// wait for connectionto arrive, then display connection info
private void waitForConnection() throws IOException
{
System.out.println("Waiting for connection\n");
connection = server.accept();
System.out.println("Connection " + counter + " received from: "
+ connection.getInetAddress().getHostName());
}
// get streams to send and receive data
private void getStreams() throws IOException
{
output = new ObjectOutputStream(connection.getOutputStream());
output.flush();
input = new ObjectInputStream(connection.getInputStream());
System.out.println("\nGot I/O streams\n");
}
private void sendData(String message)
{
try
{
output.writeObject(message);
output.flush();
System.out.println("\nCLIENT>>>" + message);
}
catch (IOException ioException)
{
System.out.println("\nError writing object");
}
}
// close streams and socket
private void closeConnection() throws IOException
{
try
{
System.out.println("\nUser terminated connection");
output.close();
input.close();
connection.close();
}
catch (Exception ex)
{
Logger.getLogger(SASSServer.class.getName()).log(Level.SEVERE, null, ex);
}
}
// process connection with client
public void processConnections() throws Exception
{
String message = "SERVER>>> Connection successful";
output.writeObject(message);
output.flush();
do
{
try
{
message = (String) input.readObject();
if (message.equals("TERMINATE"))
{
closeConnection();
runServer();
}
else
{
System.out.println("XML string being created into document : " + message);
Document d = CreateDocumentFromString(message);
String xmlname = "ServerData.xml";
x.saveDoc(d, xmlname);
processXML(xmlname);
System.out.println("Document " + xmlname + " has been created" );
System.out.println("\n Message: " + message);
}
}
catch (ClassNotFoundException classNotFoundException)
{
System.out.println("\nUnknown object type received");
}
}
while (!message.equals("CLIENT>>> TERMINATE"));
}
客户端：
// the thread that will be communicating with the server
public class ServerConnection extends Thread
{
// the I/O streams that will be receiving/sending data from/to the
// server
private ObjectOutputStream output;
private ObjectInputStream input;
private Socket client;
@Override
public void run()
{
try
{
// Step 1: Create a Socket to make connection
connectToServer();
// Step 2: Get the input and output streams
getStreams();
// Step 3: Process connection
processConnection();
// Step 4: Close connection
//closeConnection();
}
catch (IOException e)
{
Log.e("CONNECTION", e.getMessage());
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
private void connectToServer() throws IOException {
addMessage("Attempting connection\n");
client = new Socket(##IP Address##, 5001);
addMessage("Connected to: " + client.getInetAddress().getHostName());
}
private void getStreams() throws IOException
{
output = new ObjectOutputStream(client.getOutputStream());
output.flush();
input = new ObjectInputStream(client.getInputStream());
connection.sendData("You got the streams");
addMessage("Got I/O streams");
}
private void processXML(String m) throws Exception
{
addMessage(m);
}
public void processConnection() throws Exception
{
do
{
try
{
message = (String) input.readObject();
addMessage(message);
processXML(message);
}
catch (ClassNotFoundException classNotFoundException)
{
addMessage("ERROR: Unknown object type received");
} catch (OptionalDataException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
while (!message.equals("SERVER>>> TERMINATE"));
}
private void sendData(String message) {
try {
output.writeObject(message);
output.flush();
addMessage("CLIENT>>>" + message);
} catch (IOException ioException) {
addMessage("ERROR: Error writing object");
}
}
private void closeConnection() throws IOException {
addMessage("Closing connection");
output.close();
input.close();
client.close();
}
}
清单：
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="example02"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk
android:minSdkVersion="8"
android:targetSdkVersion="17" />
<uses-permission android:name="android.permission.INTERNET" />
<application
android:allowBackup="true"
android:icon="@drawable/ic_launcher"
android:label="@string/app_name"
android:theme="@style/AppTheme" >
<activity
android:name="MainActivity"
android:label="@string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity
android:name="LoginActivity"
android:label="@string/app_name" >
</activity>
<activity
android:name="AddTutor"
android:label="@string/title_activity_add_tutor" >
</activity>
<activity
android:name="InsertTutor"
android:label="@string/title_activity_insert_tutor" >
</activity>
</application>
</manifest>
我在两个Android活动中都运行完全相同的客户端代码，但是第二个活动却从未得到我的流。 请告诉我我哪里出错了，因为我沮丧地拔头发。
答案 0 :(得分：0)
我很傻。我忘了在我的清单中添加互联网权限。对于有这个问题的人，我已经解决了。