diff -uNr freecol-1.1.0.orig/build.xml freecol-1.1.0/build.xml
--- freecol-1.1.0.orig/build.xml	2023-05-07 12:51:32.000000000 +0200
+++ freecol-1.1.0/build.xml	2023-10-01 13:20:04.107000000 +0200
@@ -9,7 +9,7 @@
         the metaserver, distribution packages, running tests
         and creating documentation.
     </description>
-    <property name="java.target.version" value="11"/>
+    <property name="java.target.version" value="17"/>
     <property name="freecol.name" value="freecol"/>
     <property environment="env"/>
     <property name="freecol.data.dir" value="${basedir}/data"/>
@@ -387,7 +387,7 @@
                         <authors>
                             <author name="The FreeCol Team" email="developers@freecol.org" />
                         </authors>
-                        <javaversion>11</javaversion>
+                        <javaversion>17</javaversion>
                     </info>
                     <guiprefs width="640" height="480" resizable="no">
                         <laf name="looks">
@@ -594,7 +594,7 @@
                     mainclass="${freecol.main.class}"
                     version="${freecol.version}"
                     vmoptions="-Xmx2G -Dapple.awt.fakefullscreen=true"
-                    jvmversion="1.11"
+                    jvmversion="1.17"
                     arguments="--windowed --freecol-data FreeCol.app/Contents/Resources/"
                     stubfile="${freecol.build.dir}/skeletons/universalJavaApplicationStub"
                     useJavaXKey="true"