How is Mojarra different from Sun's JSF Reference Implemenation?
Is it just a later version? Is it simply a rename?
The Sun JSF Reference Implementation, also known as Sun JSF RI, was named like that, just "JSF RI", from the beginning on until version 1.2_08. The dev team found it an extremely boring and nothing-saying name. They would like to participate with the fancy product code name hype and wanted to have it in line with the "Glassfish" project which JSF RI is part of. After some user community polls (initiated by the good ol' forums.sun.com), the name "Mojarra" was been chosen. Since version 1.2_08, the name "JSF RI" has been replaced by "Mojarra". But it's essentially the same implementation. In other words, Mojarra is the JSF Reference Implementation.
Later, when Sun was taken over by Oracle, the company name "Sun" was obviously replaced by "Oracle".
See also:
Mojarra is the new name of the Sun's (sorry now Oracle) original JSF reference implementation (also known as JSF RI) from *version 1.2_08* onwards. Sun wanted a BUZZ word for its JSF implementation, so they gave a new name to their JSF implementation.
Mojarra is the default JSF shipped with servers like Glassfish ..etc
Mojarra is the reference implementation of the Oracle JSF 1.x/2.x spec.
来源：https://stackoverflow.com/questions/7162190/what-is-mojarra