  Context: The Javalambre Photometric Local Universe Survey (J-PLUS) is an
observational campaign that aims to obtain photometry in 12 ultraviolet-visible
filters (0.3-1 {\mu}m) of approximately 8 500 deg{^2} of the sky observable
from Javalambre (Teruel, Spain). Due to its characteristics and strategy of
observation, this survey will let us analyze a great number of Solar System
small bodies, with improved spectrophotometric resolution with respect to
previous large-area photometric surveys in optical wavelengths. Aims: The main
goal of this work is to present here the first catalog of magnitudes and colors
of minor bodies of the Solar System compiled using the first data release (DR1)
of the J-PLUS observational campaign: the Moving Objects Observed from
Javalambre (MOOJa) catalog. Methods: Using the compiled photometric data we
obtained very-low-resolution reflectance (photospectra) spectra of the
asteroids. We first used a {\sigma}-clipping algorithm in order to remove
outliers and clean the data. We then devised a method to select the optimal
solar colors in the J-PLUS photometric system. These solar colors were computed
using two different approaches: on one hand, we used different spectra of the
Sun, convolved with the filter transmissions of the J-PLUS system, and on the
other, we selected a group of solar-type stars in the J-PLUS DR1, according to
their computed stellar parameters. Finally, we used the solar colors to obtain
the reflectance spectra of the asteroids. Results: We present photometric data
in the J-PLUS filters for a total of 3 122 minor bodies (3 666 before outlier
removal), and we discuss the main issues of the data, as well as some
guidelines to solve them
