>>> How can a JavaBeans can be called as a Client-side component model?
OK, you are slightly misuderstnding the article at the link you supplied. JavaBeans represent a client-side model by way of modelling the client's requirements.
Take for example, a JSP page that asks for a username, a password and a telephone number. In this sense a JavaBean, residing on the server would be instantiated to hold this information (username, password, tel number), and the bean would be populated when the client clicked "send data now" or whatever. This bean now represents the clients login details, and so is a "component model" which represents the client.
Hope this clears up things.
Beware that JavaBeans and EJB (Enterprise JavaBeans) are VERY different kettles of fish.