dita-ot requires java 17 or higher.
Set JAVA_HOME accordingly.

--- a/bin/dita
+++ b/bin/dita
@@ -20,6 +20,9 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+eval "$(gjl -v -p dita-ot-bin)"
+JAVA_HOME=$(java-config-2 --select-vm "${gjl_vm}" -g JAVA_HOME)
+
 # Extract launch and ant arguments, (see details below).
 ant_exec_args=
 for arg in "$@" ; do