Portlets are areas that you create to add and display content. Portlets can be added left and right of the central area of the body and can contain a myriad of content, ranging from news, events, calendars, RSS feeds, collections, plain text, etc. In addition, you can set properties and policies for displaying portlets.
you want to use the portlet when you have content that you want to focus on, such as news. You need to provide configuration data for the item. - that is, the number of entries to display. You want to give content editors a choice about when and where to display content. You want to show this only to some groups or users.
Web Services, on the other hand:
Allows applications to provide their services “progammatically”, that is, services can be called by programs
Includes software running on other computers (may be a desktop, mobile phone, PDA, etc.) for invoking operations opened by web applications
if you are trying to determine the historical portal of the main differences, portlets have three levels of architechture (client, middle level, backend), this causes two weaknesses:
- Different portal groups do not have a well-established way of sharing services.
- Various technologies (Java, Perl, CORBA, EJB) at the middle level.
- Various protocols (GRAM, IIOP, ...)
- Consequently, a lot of redundancy, rethinking
- Example: batch script generation
therefore, web services solve the problem of sharing services and reduce redundancy.
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