I am trying to install emacs on an Oracle Linux machine and configuration says:

configure: error: You seem to be running X, but no X development libraries
were found. You should install the relevant development files for X
and for the toolkit you want, such as Gtk+, Lesstif or Motif. Also make
sure you have development files for image handling, i.e.
tiff, gif, jpeg, png and xpm.


However, I can find gtk2-2.18.9-12.el6.x86_64 installed on the machine. Could anyone help advise what I should do next? ( Sorry I am still new to linux, please forgive me if this is really a dumb question.)

"development libraries" are used in compiling from source. I don't know anything about Oracle but in many distributions you install packages whose names end in "-dev". libx11-dev would be an example.
jdk