updates to generic infrastructure

java.mk

@@ -9,10 +9,22 @@ ifeq ($(OS),Windows_NT)
       JAVAC = "$(JDIR)"/bin/javac
       JAVA = "$(JDIR)"/bin/java
     else
-      ## remove the # symbols from the two lines below, and write in
-      ## the path to javac and java on your system, such as
-      # JAVAC = /c/Program\ Files/Java/jdk-18.3/bin/javac
-      # JAVA = /c/Program\ Files/Java/jdk-18.3/bin/java
+      ifneq ($(wildcard /c/Program\ Files/Java/jdk-10*),)
+        JDIR = $(wordlist 1,2,$(wildcard /c/Program\ Files/Java/jdk-10*))
+        JAVAC = "$(JDIR)"/bin/javac
+        JAVA = "$(JDIR)"/bin/java
+      else
+        ifneq ($(wildcard /c/Program\ Files/Java/jdk-11*),)
+          JDIR = $(wordlist 1,2,$(wildcard /c/Program\ Files/Java/jdk-11*))
+          JAVAC = "$(JDIR)"/bin/javac
+          JAVA = "$(JDIR)"/bin/java
+        else
+          ## remove the # symbols from the two lines below, and write in
+          ## the path to javac and java on your system, such as
+          # JAVAC = /c/Program\ Files/Java/jdk-18.3/bin/javac
+          # JAVA = /c/Program\ Files/Java/jdk-18.3/bin/java
+        endif
+      endif
     endif
   endif
 else