jsp Returns no result

Question

There java class that executes and returns the result

package Test;
import static java.lang.System.out;
import java.util.ArrayList;
import java.util.List;
import org.asteriskjava.manager.ManagerConnection;
import org.asteriskjava.manager.ManagerConnectionFactory;
import org.asteriskjava.manager.action.CommandAction;
import org.asteriskjava.manager.response.CommandResponse;



public class Manager
{
    private ManagerConnection c;

    public Manager() throws Exception
    {
        ManagerConnectionFactory factory = new ManagerConnectionFactory(
                "tttt", "admin", "ttt");
        c =  factory.createManagerConnection();
    }

    public void run() throws Exception
    {
        c.login();

        CommandAction action;
        CommandResponse response;
        List<String> list = new ArrayList<String>();


        action = new CommandAction();
        action.setCommand(" sip show peers");
        response = (CommandResponse) c.sendAction(action);

        list = response.getResult();
        for (String s : list) {
            if (s.contains("VOIP")) {
            out.print(s);

            }
        }

        c.logoff();
    }

    public static void main(String[] args) throws Exception
    {
        new Manager().run();


    }
}

The result of :

TEST         172.28.1.1                                  a             5060     OK (4 ms)                                    tes          172.28.1.1                                  a             5060     OK (2 ms)                                      at Test.Manager.main(Manager.java:50)
Java Result: 1

jsp:

<%@page import="Test.Manager" %>
<%
    Manager o = new Manager();
    o.run();
    out.print(o);
%>

When you call the JSP in the browser , I see that the code is executed ( It is evident that he Rushed to the server and received data ) but on the page in the browser does not display the result of execution. Tell me which way to dig.

Do you see the number if you go to "view page source" in the browser? — BretC, Apr 15 '15 at 15:12
Yes, I see the source code . But the output of a class is not there — santer, Apr 15 '15 at 15:14
Are you sure this even compiles? Where does "out" come from in your "run" method? Don;t you need to pass in "out" to the run method from the page? Also, in the JSP, you are doing "out.print(o)". As your Manager class does not have a toString method, I'd expect this to output something horrible like "Manager@1befc" or something — BretC, Apr 15 '15 at 15:17
All compiled and displayed as you said "Test.Manager@6d787352" — santer, Apr 15 '15 at 15:19
agree with @Bret, you need a `toString()` if you want to output an object. — Sid Zhang, Apr 15 '15 at 15:20
You are using a static import - `import static java.lang.System.out;` and then using `out.print(s);` which sends the output to the IO console. You need an instance of `PrintWriter` anyway something along the line - `PrintWriter out = HttpServletResponse#getWriter();` — Tiny, Apr 15 '15 at 15:25
Your JSP has no code to display anything. Also, you should [avoid Java code in JSPs](http://stackoverflow.com/questions/3177733/how-to-avoid-java-code-in-jsp-files). — GriffeyDog, Apr 15 '15 at 15:31
@thoitbk Your option displays on the page "Test.Manager@535b6e7d " — santer, Apr 15 '15 at 16:00

score 0 · Accepted Answer · answered Apr 15 '15 at 16:31

You need some way to capture the string you are building, then output it to the generated HTML page. I have updated your run method to return a copy of the string you are outputting.

public class Manager
{
    private ManagerConnection c;

    public Manager() throws Exception
    {
        ManagerConnectionFactory factory = new ManagerConnectionFactory(
                "tttt", "admin", "ttt");
        c =  factory.createManagerConnection();
    }

    public String run() throws Exception
    {
        c.login();

        CommandAction action;
        CommandResponse response;
        List<String> list = new ArrayList<String>();
        StringBuilder sb = new StringBuilder();

        action = new CommandAction();
        action.setCommand(" sip show peers");
        response = (CommandResponse) c.sendAction(action);

        list = response.getResult();
        for (String s : list) {
            if (s.contains("VOIP")) {
            out.print(s);
            sb.append(s);
            }
        }

        c.logoff();
        return sb.toString();
    }

    public static void main(String[] args) throws Exception
    {
        new Manager().run();
    }
}

Now update the JSP to show the string on the HTML page - not in your console.

<%@page import="Test.Manager" %>
<%
    Manager o = new Manager();
    String output = o.run();
%>
<%= output %>

I also do not recommend using scriplets, but this should get your code working.

jsp Returns no result

1 Answers1