JUnit test on URLConnection, use EasyMock?

Hey, have been trying to work this out for last day or so but hitting brick wall. Trying to unit test this bit of code. But not sure if need to use EasyMock or not?? Seem few examples online but seem to be using older techniques.

public boolean verifyConnection(final String url) {
    boolean result;

    final int timeout = getConnectionTimeout();
    if (timeout < 0) {
        log.info("No need to verify connection to client. Supplied timeout = {}", timeout);
        result = true;
    } else {
        try {
            log.debug("URL: {} Timeout: {} ", url, timeout);

            final URL 开发者_Go百科targetUrl = new URL(url);
            final HttpURLConnection connection = (HttpURLConnection) targetUrl.openConnection();

            connection.setConnectTimeout(timeout);
            connection.connect();
            result = true;
        } catch (ConnectException e) {
            log.warn("Could not connect to client supplied url: " + url, e);
            result = false;
        } catch (MalformedURLException e) {
            log.error("Malformed client supplied url: " + url, e);
            result = false;
        } catch (IOException e) {
            log.warn("Could not connect to client supplied url: " + url, e);
            result = false;
        }
    }
    return result;
}

It just take's in a url checks its valid and returns T or F.

---

I have always observed that Mocking Can be avoided as much as possible because it can lead to difficult to maintain JUnit tests and defeat the whole purpose.

My suggestion would be to create a temporary server on your local machine from a JUnit itself. At the beginning of JUnit you can create a server(not more than 10-15 lines of coding required) using Java sockets and then in your code pass the URL for the local server. This way you are reducing mocking and ensuring maximum code coverage.

Something like this -

public class SimpleServer extends Thread {

public void run() {
    try {
        serverSocket = new ServerSocket(port);

          while (true) {
            Socket s = serverSocket.accept(); 
          }
    } 
    catch (IOException e) {
            e.printStackTrace();
    }
    finally {
        serverSocket = null;
    }
}
}

---

If you want to mock this method, I'd recommend passing in the URL rather than the String. Don't have your method create the URL it needs; let the client create the URL for you and pass it in. That way your test can substitute a mock if it needs to.

It's almost a dependency injection idea - your method should be given its dependencies and not create them on its own. The call to "new" is the dead giveaway.

It's not a drastic change. You could overload the method and have two signatures: one that accepts a URL string and another that accepts the URL itself. Have the first method create the URL and call the second. That way you can test it and still have the method with the String signature in your API for convenience.

---

Trying to set up mock implementation of the HttpURLConnection. Like

public class MockHttpURLConnection extends HttpURLConnection {'

then added method to class to override

' protected HttpURLConnection createHttpURLConnection(URL url)
        throws IOException {
    return (HttpURLConnection) url.openConnection();
}

So test looking something like this:

@Test
public void testGetContentOk() throws Exception
{
    String url = "http://localhost";

    MockHttpURLConnection mockConnection = new MockHttpURLConnection();

    TestableWebClient client = new TestableWebClient();
    client.setHttpURLConnection(mockConnection);

    boolean result = client.verify(url);

    assertEquals(true, result);
}

@Test
public void testDoesNotGetContentOk() throws Exception
{
    String url = "http://1.2.3.4";

    MockHttpURLConnection mockConnection = new MockHttpURLConnection();

    TestableWebClient client = new TestableWebClient();
    client.setHttpURLConnection(mockConnection);

    boolean result = client.verify(url);

    assertEquals(false, result);
}

/**
 * An inner, private class that extends WebClient and allows us
 * to override the createHttpURLConnection method.
 */
private class TestableWebClient extends WebClient1 {

    private HttpURLConnection connection;

    /**
     * Setter method for the HttpURLConnection.
     *
     * @param connection
     */
    public void setHttpURLConnection(HttpURLConnection connection)
    {
        this.connection = connection;
    }

    /**
     * A method that we overwrite to create the URL connection.
     */
    @Override
    public HttpURLConnection createHttpURLConnection(URL url) throws IOException
    {
        return this.connection;
    }
}

First part passed but is getting true for false dummy test, thanks for feedback back so far best site I have found for help. So let me know if think on right track