note versions, updated javadoc, Java openjdk21.0.1

build.xml

@@ -47,7 +47,35 @@ POSSIBILITY OF SUCH DAMAGE.
     <property name="specificationsDirectory" location="specifications"/>
     <import   file="specifications/build.xml"/> -->
 
-    <target name="all">
+    <target name="versions" description="show tool versions and environment values">
+        <echo>ant -version</echo>
+        <exec executable="ant"     dir="." vmlauncher="false">
+            <arg value="-version"/>
+        </exec>
+        <echo>java -version</echo>
+        <exec executable="java"    dir="." vmlauncher="false">
+            <arg value="-version"/>
+        </exec>
+        <echo></echo>
+        <!-- Ant environment variables https://ant.apache.org/manual/Tasks/property.html -->
+        <echo>  ANT_HOME=${env.ANT_HOME}</echo>
+        <echo> JAVA_HOME=${env.JAVA_HOME}</echo>
+        <echo>CLASSPATH=${env.CLASSPATH}</echo>
+    <!--<echo>USER      =${env.USER}</echo> -->
+        <!-- https://stackoverflow.com/questions/949678/ant-is-using-wrong-java-version -->
+        <!--echo>javac source/target      $java.source=${java.source}</ -->
+        <echo>Java/JVM version    $ant.java.version=${ant.java.version}</echo>
+        <echo>Java/JVM detail version $java.version=${java.version}</echo>
+        <echo>Ant version              $ant.version=${ant.version}</echo>
+        <echo>Configuration settings:  https://savage.nps.edu/Savage/developers.html</echo>
+        <!-- TODO Netbeans version -->
+        <!-- TODO Netbeans project version -->
+        <!-- DEBUG: to show all environment and local properties, add
+        <echoproperties/> -->
+        <echo message="==========================================="/>
+    </target>
+    
+    <target name="all" depends="versions">
         <ant dir="examples"    target="clean"/>
         <ant dir="examples"    target="jar"/>
         <ant dir="assignments" target="clean"/>