GWT‘s Same Origin Policy (SOP) problem is common especially for newbies. This happens if your GWT front end client accesses a remote service that is hosted in the same local domain in your PC but having a different port.
Browsers still considers this a violation of the SOP policy. I have read that Internet Explorer has a lax web security policy so you may be able to use that without encountering this restriction. However, Internet Explorer sucks and Firefox is just too damn heavy to load even with just one tab.
So I am left with Google Chrome. You can run Google Chrome with web security disabled but I would advise you to create it as a shortcut in Windows and create an alias in Mac OS. Here is how I did them.
- right click anywhere on your desktop, choose New > Shortcut
- then type this in the text field C:\Users\[USERNAME]\AppData\Local\Google\Chrome\Application\chrome.exe –allow-file-access-from-files –disable-web-security
- click OK
- open Terminal
- edit your .profile file
- add this to the end of the file alias chromegwt=’/Applications/Google\ Chrome.app/Contents/MacOS/Google\ Chrome –disable-web-security’
- save file
- close Terminal window or open a new Terminal window tab then type chromegwt and you should then see Google Chrome launch without web security.
Note: you can rename it any name you want. I just used chromegwt so I would know that this Chrome is used only for GWT purposes.
Remember not to use this same browser when browsing the web as it can lead to disastrous results.