Well, to begin, let us look at all 16 MBTI types. We may eliminate all the P types, leaving us with 8. 4 are IxxJs and 4 are ExxJs. All Js use both an introverted perception function (Ni or Si) combined with an extroverted judgment function (Te or Fe). ExxJs have the extroverted judgment function as their dominant function, while the introverted perception function as their auxiliary function (take ENFJ, for instance, which has Fe as dom. and Ni as aux.). Extroverted Judging functions (Te and Fe) are decisive, judgment-oriented functions (hence the name). Since these are the dominant functions of ExxJs, ExxJs are thus the most proactive and forceful (as well as rigid). Contrast this with IxxPs who are most passive and detached (as well as nonchalant). IxxJs are less decisive and judgmental than ExxJs, because they are introverted, yet they still are to a considerable extent, since they still use an extroverted judgment function to deal with the external world. For your use, here is a chart of all J types:
Fe = empathy, outward expression of emotion, sympathy, helpfulness, etc.
Te = pragmatic action, application, organization, strategy, etc.
Ni = imagined scenarios, prediction, vagueness, the future, etc.
Si = the past, details, atmosphere, one's state of being, etc.
Thus we get the following:
NFJ = teaching, spirituality, being a "martyr" or "savior," activism, etc.
STJ = logistics, organization, data collection, etc.
SFJ = community service, tradition, keeping society hold together, helping people, etc.
NTJ = business, strategy, planning, prediction, etc.