How to stop and start existing application in tomcat

[Robert Jack]

Hi,

I developed simple application "myproject" and deployed in tomcat-6.0.29.

Application stopped when i execute this "http://localhost:8080/manager/stop?path=/myproject".

Is possible to stop this application using java program?

Is possible to start this application using java program?

Help me.
Thanks in advane

[Eswar Nec]

Hi jack,

Try this

Process p = r.exec("wget http://tomcatusername:tomcatepassword@localhost:8080/manager/" + action + "?path=/myproject -O - -q");

[Robert Jack]

Hi eswar. Thanks for your support.

I check your code. It works fine in Linux Ubuntu. Windows not support
I got error when execute in windows

Error is:

  
Error occur: java.io.IOException: Cannot run program "wget": 
CreateProcess error=2, The Stystem cannot find the file specified

Anyone help me.

[Tim Holloway]

One of the reasons why Linux is so much better for software development than Windows is that Linux comes with an immense number of developer utility programs. Windows does not.

You have 2 choices.

1. You can download and install Cygwin, which allows you to run Linux programs under Windows

2. You can google around and find and install a Windows native "wget" program from some third party.

For a single need, I recommend answer #2, since Cywin is practically an OS in its own right, but either solution will work.

[William Brogden]

Whats wrong with using java.net.HttpURLConnection and the rest of the standard library to do a GET request and read the response?

Why would you need to create a Process?

Bill

[Tim Holloway]

Actually, now that I look at the original question, yes, there are several ways in Java to start/stop apps in Java code.

I believe JSR-77 specifies one of them. JMX provides another, I think. Neither requires the existence of an external program such as wget.

[Robert Jack]

Tim Holloway wrote:Actually, now that I look at the original question, yes, there are several ways in Java to start/stop apps in Java code.

I believe JSR-77 specifies one of them. JMX provides another, I think. Neither requires the existence of an external program such as wget.

Hi Tim Holloway,
Thanks for your response.
But i can't get your idea.

Can you give me some more idea about your answer or reference,
regarding start/stop an existing application in tomcat using java code.

Help me.
Thanks in advance.

[Robert Jack]

William Brogden wrote:Whats wrong with using java.net.HttpURLConnection and the rest of the standard library to do a GET request and read the response?

Why would you need to create a Process?

Bill

Hi William Brogden, Thanks for your effort
I got exception when i use HttpURLConnection. I don't know, where i made mistake?
Error is
IOException: java.io.IOException: Server returned HTTP response code: 401 for URL: http://localhost:8080/manager/html/stop?path=/myproject
My code is:

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.ProtocolException;
import java.net.URL;

public class SimpleHTTPRequest
{
    public static void main(String[] args)
    {
        HttpURLConnection connection = null;
        BufferedReader rd = null;
        StringBuilder sb = null;
        String line = null;

        URL serverAddress = null;
        try
        {
            serverAddress = new URL("http://localhost:8080/manager/html/stop?path=/myproject ");

            //Set up the initial connection
            connection = (HttpURLConnection) serverAddress.openConnection();
            connection.setRequestMethod("GET");
            connection.setDoOutput(true);
            connection.setReadTimeout(10000);

            connection.connect();

            rd = new BufferedReader(new InputStreamReader(connection.getInputStream()));
            sb = new StringBuilder();

            while ((line = rd.readLine()) != null)
            {
                sb.append(line + '\n');
            }
            System.out.println(sb.toString());
        }
        catch (MalformedURLException e)
        {
            System.out.println("MalformedURLException: " + e);
        }
        catch (ProtocolException e)
        {
            System.out.println("ProtocolException: " + e);
        }
        catch (IOException e)
        {
            System.out.println("IOException: " + e);
        }
        finally
        {
            connection.disconnect();
            rd = null;
            sb = null;
            connection = null;
        }
    }
}

Help me.
Thanks in advance

[William Brogden]

401 = UNAUTHORIZED - the management app is protected, you need a user in the "managememt" role in order to run the manager app.

Bill

[Robert Jack]

William Brogden wrote:401 = UNAUTHORIZED - the management app is protected, you need a user in the "managememt" role in order to run the manager app.

Bill

Thanks for your support.

How i configure the 'user' in the management role in order to run the manage application?

Help me
Thanks in advance.

[Robert Jack]

I check My tomcat-user.xml file. But its not working

I need to add any role in my tomcat-user.xml file.

<?xml version='1.0' encoding='utf-8'?>

<tomcat-users>

<role rolename="manager"/>
<user username="tomcat" password="s3cret" roles="manager" />

</tomcat-users>

[Tim Holloway]

There should be model role definitions in the originally-supplied tomcat-users.xml file that will suffice. Although as shipped they may be commented out.

When a server returns a 401 response, the client must log in. That means that a request containing the encoded userid and password must be sent to Tomcat to be validated. Once your client app has logged in, then you can send Tomcat admin URLs.

And, no, I don't have any code like that lying around. I'd have to do the same thing I recommend that you do: Google. Useful magic words include "RFC" and "Basic Authentication", since the definitive documentation for handling a 401 (Basic Authentication) request is one of the Internet RFC documents, which will typically include simple examples of how things are done. If your client app hasn't disabled cookies, a successful login request will return a cookie which will be used to maintain the session context for future requests. And, if you're using the HttpURLConnection, cookie handling is completely automatic, so you don't need to code anything for it.

[William Brogden]

Note that you have to restart Tomcat if you change the users xml file.

Test by using the html interface with a browser - http://yoursite/manager/html/list - you should get a security dialog to enter name and password.

If that works then http://username:userpw@yoursite/manager.... etc should work as the url to GET

Bill

[Tim Holloway]

William Brogden wrote:Note that you have to restart Tomcat if you change the users xml file.

That was true with the original MemoryRealm. I think its newer derivatives are smarter about that. Can't hurt, though.

If that works then http://username:userpw@yoursite/manager.... etc should work as the url to GET

Or better, use the https protocol. The http protocol is vulnerable to wire sniffing. Even if only intranet clients control Tomcat this way. it's good practice.

[Robert Jack]

Not working.
My "tomcat-users.xml" file content

<tomcat-users>
    <role rolename="manager"/>
    <user username="tomcat" password="s3cret" roles="manager"/>
</tomcat-users>

I deploy my web application in my local system. application name is "jsfproject"
Then my java code like this

       String url = "http://tomcat:s3cret@localhost:8080/manager/html/stop?path=/jsfproject";
       .....
       .....

Eventhough i got message "Method failed: HTTP/1.1 401 Unauthorized". I don't know whats wrong my code


Step 1 : I create simple JSF project. and deployed in tomcat. project name "jsfproject"

Step 2 : I create another one JSF application "Demo Project"

Stpe 3 : This "Demo Project" have only one "test.jsp" page. I create only one button "Stop JSF project" in that test.jsp page

Stpe 4 :

<h:commandButton id="testButton" 
                      action="#{StopBean.stopJSFProject}"
                      value="Stop JSF project" />

Step 5 :

....
....
public class StopBean
{
    ....
    .....
    public String stopJSFProject()
    {
         System.out.println("Going to stop the application......"));
          String url = "http://tomcat:s3cret@localhost:8080/manager/html/stop?path=/jsfproject";         
           
         HttpClient client = new HttpClient();        
         GetMethod method = new GetMethod(url);        
         method.getParams().setParameter(HttpMethodParams.RETRY_HANDLER,
                new DefaultHttpMethodRetryHandler(3, false));
        try
        {           
            int statusCode = client.executeMethod(method);
            if (statusCode != HttpStatus.SC_OK)
            {               
                System.err.println("Method failed: " + method.getStatusLine());
            }
            byte[] responseBody = method.getResponseBody();           
            System.out.println(new String(responseBody));
        }
        catch (HttpException e)
        {           
            System.err.println("Fatal protocol violation: " + e.getMessage());
            e.printStackTrace();
        }
        catch (IOException e)
        {            
            System.err.println("Fatal transport error: " + e.getMessage());
            e.printStackTrace();
        }
        finally
        {          
            method.releaseConnection();
        }     
         return null;
    } 
}

I got the following message when i click "stop JSF project" button

Going to stop the application......
Method failed: HTTP/1.1 401 Unauthorized


Help me,
Thanks for valuable effort