java: examples: split in two

* examples/java: Split in...
* examples/java/simple, examples/java/calc: these.

examples/java/simple/Makefile

@@ -0,0 +1,26 @@
+# This Makefile is designed to be simple and readable.  It does not
+# aim at portability.  It requires GNU Make.
+
+BISON = bison
+JAVAC = javac
+JAVA = java
+XSLTPROC = xsltproc
+
+all: Calc.class
+
+%.java %.xml %.gv: %.y
+	$(BISON) $(BISONFLAGS) --xml --graph=$*.gv -o $*.java $<
+
+%.class: %.java
+	$(JAVAC) $(JAVACFLAGS) $<
+
+run: Calc.class
+	@echo "Type arithmetic expressions.  Quit with ctrl-d."
+	$(JAVA) $(JAVAFLAGS) Calc
+
+html: Calc.html
+%.html: %.xml
+	$(XSLTPROC) $(XSLTPROCFLAGS) -o $@ $$($(BISON) --print-datadir)/xslt/xml2xhtml.xsl $<
+
+clean:
+	rm -f *.class Calc.java Calc.html Calc.xml Calc.gv