  Jet production in high energy proton-proton ($p+p$) collisions is dominated
by hard QCD subprocesses such as gluon-gluon and quark-gluon scatterings.
Therefore $p+p$ is an effective tool to probe the internal distribution of
gluons in the proton. The STAR Collaboration at the Relativistic Heavy Ion
Collider (RHIC) is using longitudinally polarized $p+p$ collisions at the
center of mass energies, $\sqrt{s} = $ 200 and 510 GeV, to study the
cross-section and double spin asymmetries, $A_{LL}$, of inclusive jet and
di-jet production. The measurements at $\sqrt{s} = $ 200 GeV showed that the
jet cross-sections are well described by the next-to-leading-order perturbative
QCD calculations after underlying event and hadronization corrections. The
previous 2009 $\sqrt{s} = $ 200 GeV inclusive jet asymmetry $A_{LL}$
measurement at pseudo-rapidity $|\eta| < $ 1.0 showed the first experimental
evidence of a non-zero gluon polarization for partonic momentum fraction, $x >
0.05$. The inclusive jet $A_{LL}$ measurement at $\sqrt{s} = $ 510 GeV allows
to explore the gluon polarization to smaller $x \sim 0.02$. The 2012 inclusive
jet $A_{LL}$ and cross-section measurements at $\sqrt{s} =$ 510 GeV, the
techniques used in the jet analysis including underlying event correction, and
future perspectives related to jet measurements at STAR will be presented.
