How to Map System.out and System.in to SWT controls

问题

I am working on on a tool to connect to a remote server using jcraft.JSch (ssh to Unix server) and return the output and display its output. The script works fine when channel input outputs are System.in and System.out. But when I try with SWT controls, it is not able to

1. display the exact output I am getting with System.out

2. read from SWT Text control emulating System.in

   public void create() {
   
   dialogShell = new Shell(dialogShell, SWT.PRIMARY_MODAL | SWT.SHEET | SWT.RESIZE);
   GridLayout gridLayout = new GridLayout();
   gridLayout.numColumns = 2;
   dialogShell.setLayout(gridLayout);
   final Text logText = new Text(dialogShell, SWT.MULTI | SWT.BORDER| SWT.READ_ONLY);
   GridData gridData0 = new GridData(GridData.FILL,GridData.FILL, true, true);
   gridData0.horizontalSpan = 2;
   logText.setLayoutData(gridData0);
   
   origOutPS = System.out;
   origErrPS = System.err;
   
   
   final Text cmdText = new Text(dialogShell, SWT.BORDER | SWT.V_SCROLL);
   final Button RunButton = new Button(dialogShell, SWT.PUSH);
   GridData gridDatal = new GridData(GridData.BEGINNING, GridData.FILL_HORIZONTAL, true,false);
   GridData gridData2 = new GridData(GridData.END, GridData.CENTER, false,false);
   cmdText.setLayoutData(gridDatal);
   RunButton.setLayoutData(gridData2);
   RunButton.setText("Execute");
   RunButton.addSelectionListener(new runButton(dialogShell,cmdText));
   
   dialogShell.setDefaultButton(RunButton);
   dialogShell.setSize(550, 250);
   dialogShell.setText("Processing....");
   
   OutputStream out = new OutputStream() {
       public void write(int b) throws IOException {
           logText.append(String.valueOf((char) b));
       }
   
       public void write(byte[] b,int off, int len) {
           logText.append(new String(b, off, len));
       }
   };
   PrintStream ps = new PrintStream(out,true);
   System.out.println("Passing the control!");
   System.setOut(ps);
   System.setErr(ps);
   
   
   InputStream in = new InputStream() {
       @Override
       public int read() throws IOException {
           String str = cmdText.getText();
           int pos = 0;
           //test if the available input has reached its end
           //and the EOS should be returned 
           if( str != null && pos == str.length()){
               str =null;
               //this is supposed to return -1 on "end of stream"
               //but I'm having a hard time locating the constant
               return java.io.StreamTokenizer.TT_EOF;
           }
           //no input available, block until more is available because that's
           //the behavior specified in the Javadocs
           while (str == null || pos >= str.length()) {
               try {
                   //according to the docs read() should block until new input is available
                   synchronized (this) {
                       this.wait();
                   }
               } catch (InterruptedException ex) {
                   ex.printStackTrace();
               }
           }
           //read an additional character, return it and increment the index
           return str.charAt(pos++);
       }
   };
   System.setIn(in);
   
   dialogShell.addListener(SWT.Close, new closelistener());
   
   //dialogShell.addShellListener(new MyshellAdapter(logText,cmdText,RunButton));
   dialogShell.open();
   }
   

Above is the dialog and this is the output I am getting

whereas when I connect channel input output to System.in and System.out, the output is as follows

来源：https://stackoverflow.com/questions/32008173/how-to-map-system-out-and-system-in-to-swt-controls