how to show map of maps in jsp,struts

[Tanu Gulati]

I got a problem where I have to iterate and show HashMap(<HashMap>,string) on a jsp page. I am using another HashMap as a key(as per my business scenario)

can anyone help me understand how I can achieve it through JSP or struts.

[Rajkamal Pillai]

This is an earlier post I found on The Ranch.
Iterate Map through Struts

Tweak according to your situation. And feel free to post any queries...

Cheers,
Raj.

[Tanu Gulati]

This is an earlier post I found on The Ranch.
Iterate Map through Struts

I actually got this before posting on codeRanch but in my case the problem is little different I have a HashMap(say hashmap1) which contains another HashMap (say hashmap 2) , i want to get the values of hashmap2 as a group and print against a value.

[Rajkamal Pillai]

You can use the custom tags to iterate through each map and embed all of this within the correct HTML tags to get the desired display, correct?

I do not see the problem you face...

Cheers,
Raj.

[Bear Bibeault]

Custom tags are not necessary. The JSTL and EL are perfectly able to deal with Maps of any type.

[Rajkamal Pillai]

I mentioned "custom tags" as Struts relies on a few by default.

Since you mentioned JSTL and EL:

I have seen that they do not cause errors on the web page but apart from that is there any noticeable performance degradation?

Cheers,
Raj.

[Bear Bibeault]

Compared to what?

[Rajkamal Pillai]

Bear,

I was trying to compare the performance, Custom tags vs JSTL/EL.

Cheers,
Raj.

[Bear Bibeault]

Why should there be a performance difference? The JSTL and other custom tags are based on the same tag mechanism.

The EL is built into the JSP engine so it's likely highly optimized.

[Rajkamal Pillai]

Thank you, Bear.

I felt that using a Custom Tag would involve invoking the tag handler and hence added a layer altogether which might cause some (slight) overhead.

Now as EL has been built into the JSP engine and this could probably eliminate this overhead.

What I was trying to figure out is the best practices when it comes to usage of Custom Tags.

Cheers,
Raj.

[Bear Bibeault]

Best practice is to use the JSTL for what it does and only use other custom tags for things that the JSTL does not provide.

[Rajkamal Pillai]

Thank you so much Bear.

This was a doubt I have been having for quite a while.

Thanks,
Raj.