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POJava Socket read from socket in real time
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  1. POJava Socket read from socket in real time
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    copied!<p>I'm writing a java applet to simulate a ssh connection to ubuntu machine, I set up the connection, excute the command, and get back response, everything looks fine. However, I had a small issue here, I want to receive server socket response in real time, so I can simulate on Applet in real time, but it seems I receive the response while the command excution is finished. For example, I have a test tcl file, I let the excution sleep 5 seconds between each statement, I should whoe the response on applet in every 5 seconds, instead of I get all of the response in the end. Any thoughts?</p> <pre><code>/* * To change this template, choose Tools | Templates * and open the template in the editor. */ /* * ssh_applet.java * * Created on 9-Dec-2010, 11:10:06 AM */ /** * * @author xzhang */ //import javax.swing.*; import java.io.BufferedReader; import java.io.IOException; import java.io.InputStream; import java.io.OutputStream; import java.io.InputStreamReader; import ch.ethz.ssh2.Connection; import ch.ethz.ssh2.Session; import ch.ethz.ssh2.StreamGobbler; import javax.swing.*; public class ssh_applet extends javax.swing.JApplet{ private String host_name = null; private String user_name = null; private String pass_word = null; private Connection app_conn; private Session app_session; /** Initializes the applet ssh_applet */ public void init() { try { java.awt.EventQueue.invokeAndWait(new Runnable() { public void run() { initComponents(); } }); } catch (Exception ex) { ex.printStackTrace(); } } /** This method is called from within the init() method to * initialize the form. * WARNING: Do NOT modify this code. The content of this method is * always regenerated by the Form Editor. */ @SuppressWarnings("unchecked") // &lt;editor-fold defaultstate="collapsed" desc="Generated Code"&gt; private void initComponents() { ssh_input = new javax.swing.JPanel(); connect = new javax.swing.JButton(); jLabel1 = new javax.swing.JLabel(); jLabel2 = new javax.swing.JLabel(); jLabel3 = new javax.swing.JLabel(); hostname = new javax.swing.JTextField(); username = new javax.swing.JTextField(); password = new javax.swing.JPasswordField(); ssh_command = new javax.swing.JTextField(); ssh_output_pannel = new javax.swing.JPanel(); jScrollPane1 = new javax.swing.JScrollPane(); ssh_output = new javax.swing.JTextArea(); clear_text = new javax.swing.JButton(); connect.setText("Connect"); connect.addActionListener(new java.awt.event.ActionListener() { public void actionPerformed(java.awt.event.ActionEvent evt) { connectActionPerformed(evt); } }); jLabel1.setText("Host Name"); jLabel2.setText("User Name"); jLabel3.setText("Password"); hostname.setText("10.4.0.135"); username.setText("xzhang"); password.setText("Samboapple0827!"); ssh_command.addActionListener(new java.awt.event.ActionListener() { public void actionPerformed(java.awt.event.ActionEvent evt) { ssh_commandActionPerformed(evt); } }); javax.swing.GroupLayout ssh_inputLayout = new javax.swing.GroupLayout(ssh_input); ssh_input.setLayout(ssh_inputLayout); ssh_inputLayout.setHorizontalGroup( ssh_inputLayout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) .addGroup(ssh_inputLayout.createSequentialGroup() .addContainerGap() .addGroup(ssh_inputLayout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) .addComponent(jLabel1) .addGroup(ssh_inputLayout.createSequentialGroup() .addGroup(ssh_inputLayout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) .addComponent(jLabel2) .addComponent(jLabel3)) .addGap(18, 18, 18) .addGroup(ssh_inputLayout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING, false) .addComponent(username, javax.swing.GroupLayout.Alignment.TRAILING) .addComponent(password) .addComponent(hostname, javax.swing.GroupLayout.PREFERRED_SIZE, 122, javax.swing.GroupLayout.PREFERRED_SIZE)))) .addGroup(ssh_inputLayout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) .addGroup(ssh_inputLayout.createSequentialGroup() .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED) .addComponent(connect)) .addGroup(ssh_inputLayout.createSequentialGroup() .addGap(49, 49, 49) .addComponent(ssh_command, javax.swing.GroupLayout.PREFERRED_SIZE, 300, javax.swing.GroupLayout.PREFERRED_SIZE))) .addContainerGap(60, Short.MAX_VALUE)) ); ssh_inputLayout.setVerticalGroup( ssh_inputLayout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) .addGroup(ssh_inputLayout.createSequentialGroup() .addGap(14, 14, 14) .addGroup(ssh_inputLayout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE) .addComponent(jLabel1) .addComponent(hostname, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE) .addComponent(connect)) .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED) .addGroup(ssh_inputLayout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE) .addComponent(jLabel2) .addComponent(username, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)) .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.UNRELATED) .addGroup(ssh_inputLayout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE) .addComponent(jLabel3) .addComponent(password, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE) .addComponent(ssh_command, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)) .addContainerGap(18, Short.MAX_VALUE)) ); ssh_output.setColumns(20); ssh_output.setEditable(false); ssh_output.setLineWrap(true); ssh_output.setRows(5); jScrollPane1.setViewportView(ssh_output); clear_text.setText("Clear"); clear_text.addActionListener(new java.awt.event.ActionListener() { public void actionPerformed(java.awt.event.ActionEvent evt) { clear_textActionPerformed(evt); } }); javax.swing.GroupLayout ssh_output_pannelLayout = new javax.swing.GroupLayout(ssh_output_pannel); ssh_output_pannel.setLayout(ssh_output_pannelLayout); ssh_output_pannelLayout.setHorizontalGroup( ssh_output_pannelLayout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) .addGroup(ssh_output_pannelLayout.createSequentialGroup() .addContainerGap() .addGroup(ssh_output_pannelLayout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) .addComponent(jScrollPane1, javax.swing.GroupLayout.DEFAULT_SIZE, 591, Short.MAX_VALUE) .addComponent(clear_text, javax.swing.GroupLayout.Alignment.TRAILING)) .addContainerGap()) ); ssh_output_pannelLayout.setVerticalGroup( ssh_output_pannelLayout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) .addGroup(ssh_output_pannelLayout.createSequentialGroup() .addContainerGap() .addComponent(jScrollPane1, javax.swing.GroupLayout.DEFAULT_SIZE, 371, Short.MAX_VALUE) .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.UNRELATED) .addComponent(clear_text) .addContainerGap()) ); javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane()); getContentPane().setLayout(layout); layout.setHorizontalGroup( layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) .addComponent(ssh_input, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE) .addComponent(ssh_output_pannel, javax.swing.GroupLayout.Alignment.TRAILING, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE) ); layout.setVerticalGroup( layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) .addGroup(layout.createSequentialGroup() .addComponent(ssh_input, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE) .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.UNRELATED) .addComponent(ssh_output_pannel, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE) .addContainerGap(javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)) ); }// &lt;/editor-fold&gt; private void connectActionPerformed(java.awt.event.ActionEvent evt) { // TODO add your handling code here: /*get host_name*/ host_name=hostname.getText(); user_name=username.getText(); pass_word=password.getText(); /* Create a connection instance */ app_conn=new Connection(host_name); try { app_conn.connect(); /* Authenticate. * If you get an IOException saying something like * "Authentication method password not supported by the server at this stage." * then please check the FAQ. */ boolean isAuthenticated = app_conn.authenticateWithPassword(user_name, pass_word); if (isAuthenticated == false) throw new IOException("Authentication failed."); JOptionPane.showMessageDialog(null, "You are connected to host "+host_name, "Connection", JOptionPane.INFORMATION_MESSAGE); /* Create a session */ } catch(IOException e) {} } private void ssh_commandActionPerformed(java.awt.event.ActionEvent evt) { // TODO add your handling code here: String command=ssh_command.getText(); try { app_session=app_conn.openSession(); app_session.execCommand( command ); InputStream stdout = new StreamGobbler( app_session.getStdout() ); BufferedReader br = new BufferedReader(new InputStreamReader(stdout)); String line ; while( (line= br.readLine()) != null ) { ssh_output.append( line + "\n" ); //line = br.readLine(); } // DEBUG: dump the exit code System.out.println( "ExitCode: " + app_session.getExitStatus() ); // Close the session app_session.close(); } catch(Exception e) {} } private void clear_textActionPerformed(java.awt.event.ActionEvent evt) { // TODO add your handling code here: ssh_output.setText(""); } // Variables declaration - do not modify private javax.swing.JButton clear_text; private javax.swing.JButton connect; private javax.swing.JTextField hostname; private javax.swing.JLabel jLabel1; private javax.swing.JLabel jLabel2; private javax.swing.JLabel jLabel3; private javax.swing.JScrollPane jScrollPane1; private javax.swing.JPasswordField password; private javax.swing.JTextField ssh_command; private javax.swing.JPanel ssh_input; private javax.swing.JTextArea ssh_output; private javax.swing.JPanel ssh_output_pannel; private javax.swing.JTextField username; // End of variables declaration } </code></pre> <p>Here is my code,I'm using ganymed-ssh2 library, can't get where to flush</p>
 

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