why both interface and an abstract class

An interface can have no implementation.

An abstract class can have some implementation as well as abstract methods which doesn't have implementation.

We have abstract classes to have the benefit of both the interface and a class.

In an abstract class, functionalities common for a module can be implemented in the methods, at the same time the methods that must be implemented by the classes specific for an operation can also be specified/enforced.

So an abstract class is an additional facility rather than a necessity, a nice to have feature in any OO language like Java.

Mint.com - online personal money management site

Mint.com is a free online personal money management website.
It has a cool and a very simple UI.
The weakness is, this being an online tool, this is fully pre-customized for USA.
You cannot add your own account, you have to choose from the types of accounts given there.
mint collects information directly from banks and other financial institutions -- the user has to provide the credentials - username, password etc.... -- so that the user need not re-enter data (which cannot be done if the user enters his own account). Cool. Still if the user does not belong to any of these institutions, he cannot use the site, till either mint adds the users institution or the user joins one of the institutions which mint has in list.
This could have been kept optional so that the user can use the tool like he wants.
Since this requires the tie ups with the corresponding institutions, this blocks other nationals from using this site, thus the site looses a world touch .... I feel mint has made things mandatory that are to be given as an option to the user.
Otherwise this should have become a well used tool online -- something like ... GMail.

Open in a new tab

I use internet explorer 7. It gives two different for options to open links.

1. Open in a new tab (IE's new facility - looks like the big M was compelled to copy from other browsers).
2. Open in a new window (yes, it was already existing in IE).

The response to both these options is same. The link gets opened in a new window. wow.

Powered by ScribeFire.

Logging out of GMail ? Your firefox will close !

The following is my firefox version.

Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.8.1.11) Gecko/20071127 Firefox/2.0.0.11

Whenever I log out of gmail, firefox gets closed with the window you see on the left.

I use Windows Xp professional ed.

The 'dont have's

Gmail doesn't have html signature
Gmail doesn't recieve zip files as attachment(s).

Will Opera take the place of Firefox ?

(+) One thing i liked best in opera is the speed dialing.

(+) We can have 9 most clicked pages here. Whenever we want any of them we can just choose them () rather than typing them or searching for them in the bookmarks. Unlike bookmarks they dont keep staying on your browser view, they come only when you ask for a new window or a new tab. A wow to opera.

(+) Second why switched to opera is : once my system went slow, when i checked my task manager (windows) i found that firefox was taking 314 mb of my memory - of which i have already done a post : http://tech-lense.blogspot.com/2007/09/is-firefox-taking-314mb-of-our-memory.html

(+) I even found image rendering quality is better in opera than in firefox.

(+) Switching to opera from firefox was easy as well.

(-) I had one un-understandable issue with opera. A topic from my company forum (normal html) did not load in Opera. In firefox it did.

(-) In google reader, the '+' shortcut key did not work which is supposed to increase my content size in opera browser (In firefox, it is ctrl +). In most sites it works, still after increasing the size, the browser becomes sluggish and becomes slow.

(-) One more comparision to firefox : I couldn't see the horizontal slider when the content exceeded the screen size in the browser (In the page i saw, the html content did not exceed the screen size but an image in the page did). In this case too, ff is able to give the horizontal slide bar. Opera isn't.

Hope these (-) are in Opera's list to solve.

Will Opera take the place of Firefox as Firefox took the place of Internet Explorer?

Install a java game on your mobile. No help required.

Two days back i was about to install a java game on my mobile phone.

I was looking for help in internet. No clear helps on how to install.

I just copied the jar of the game to my mobile thru bluetooth. When I opened the jar (the recieved message on my mobile), the phone automatically started installing it.

So the installation is automatic. No help is required.