checkstyle @ 4.3 : Configure error - build failure

[leofiore (Leonardo)]

macports 2.7.1 macos Big Sur, x86_64

:info:build Executing:  cd "/opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_macports_release_tarballs_ports_java_checkstyle/checkstyle/work/checkstyle-src-4.3" && ant build.bindist
:debug:build system:  cd "/opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_macports_release_tarballs_ports_java_checkstyle/checkstyle/work/checkstyle-src-4.3" && ant build.bindist
:info:build Buildfile: /opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_macports_release_tarballs_ports_java_checkstyle/checkstyle/work/checkstyle-src-4.3/build.xml
:info:build -check.antlr:
:info:build build.antlr:
:info:build      [java] ANTLR Parser Generator   Version 2.7.6 (2005-12-22)   1989-2005
:info:build      [java] java.g:912: warning:Syntactic predicate superfluous for single alternative
:info:build compile.checkstyle:
:info:build     [mkdir] Created dir: /opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_macports_release_tarballs_ports_java_checkstyle/checkstyle/work/checkstyle-src-4.3/target/checkstyle
:info:build     [javac] Compiling 275 source files to /opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_macports_release_tarballs_ports_java_checkstyle/checkstyle/work/checkstyle-src-4.3/target/checkstyle
:info:build     [javac] warning: [options] bootstrap class path not set in conjunction with -source 1.4
:info:build     [javac] error: Source option 1.4 is no longer supported. Use 7 or later.
:info:build     [javac] error: Target option 1.4 is no longer supported. Use 7 or later.
:info:build BUILD FAILED

[leofiore (Leonardo)]

build log of the installation

[jmroot (Joshua Root)]

Same basic issue as #51731 and #32187, the port is in dire need of being updated to a newer upstream version.