java: add an example

* examples/java/Calc.y: New, based on test 495: "Calculator
parse.error=verbose %locations".
* examples/java/Calc.test, examples/java/local.mk: New.

* configure.ac (ENABLE_JAVA): New.
* examples/test (prog): Be ready to run Java programs.

9 files changed, 242 insertions, 1 deletions

diff --git a/Makefile.am b/Makefile.am
index 7f18f6f4..6911bc78 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -52,6 +52,7 @@ MOSTLYCLEANFILES =
 SUFFIXES =
 TESTS = $(dist_TESTS)
 check_PROGRAMS =
+check_SCRIPTS =
 dist_TESTS =
 noinst_LIBRARIES =
 
diff --git a/configure.ac b/configure.ac
index 959fc968..cce792f6 100644
--- a/configure.ac
+++ b/configure.ac
@@ -280,6 +280,7 @@ AC_SUBST([GCC])
 
 gt_JAVACOMP([1.7], [1.7])
 gt_JAVAEXEC
+AM_CONDITIONAL([ENABLE_JAVA], [test x"$CONF_JAVAC" != x && test x"$CONF_JAVA" != x])
 
 AC_CONFIG_FILES([Makefile
                  po/Makefile.in
diff --git a/examples/README b/examples/README
index 50ca4820..87f73544 100644
--- a/examples/README
+++ b/examples/README
@@ -34,6 +34,12 @@ Extracted from the documentation: "A Complete C++ Example".
 https://www.gnu.org/software/bison/manual/html_node/A-Complete-C_002b_002b-Example.html
 
 
+* Examples in Java
+
+** java/Calc.y
+The usual calculator.
+
+
 -----
 
 Local Variables:
diff --git a/examples/java/Calc.test b/examples/java/Calc.test
new file mode 100644
index 00000000..71861187
--- /dev/null
+++ b/examples/java/Calc.test
@@ -0,0 +1,26 @@
+#! /bin/sh
+
+# Copyright (C) 2018 Free Software Foundation, Inc.
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+cat >input <<EOF
+1 + 2 * 3
+EOF
+run 0 7
+
+cat >input <<EOF
+1 + 2 * * 3
+EOF
+run 0 "err: 1.5: syntax error, unexpected '*', expecting number or '-' or '(' or '!'"
diff --git a/examples/java/Calc.y b/examples/java/Calc.y
new file mode 100644
index 00000000..46c1dec2
--- /dev/null
+++ b/examples/java/Calc.y
@@ -0,0 +1,166 @@
+%language "Java"
+%name-prefix "Calc"
+%define parser_class_name {Calc}
+%define public
+
+%define parse.error verbose %locations
+%code {
+  public static void main (String args[]) throws IOException
+  {
+    CalcLexer l = new CalcLexer (System.in);
+    Calc p = new Calc (l);
+    p.parse ();
+  }
+}
+
+%code imports {
+  import java.io.StreamTokenizer;
+  import java.io.InputStream;
+  import java.io.InputStreamReader;
+  import java.io.Reader;
+  import java.io.IOException;
+}
+
+/* Bison Declarations */
+%token <Integer> NUM "number"
+%type  <Integer> exp
+
+%nonassoc '='       /* comparison            */
+%left '-' '+'
+%left '*' '/'
+%precedence NEG     /* negation--unary minus */
+%right '^'          /* exponentiation        */
+
+/* Grammar follows */
+%%
+input:
+  line
+| input line
+;
+
+line:
+  '\n'
+| exp '\n'           { System.out.println ($exp); }
+| error '\n'
+;
+
+exp:
+  NUM                { $$ = $1;                                             }
+| exp '=' exp
+  {
+    if ($1.intValue () != $3.intValue ())
+      yyerror (@$, "calc: error: " + $1 + " != " + $3);
+  }
+| exp '+' exp        { $$ = new Integer ($1.intValue () + $3.intValue ());  }
+| exp '-' exp        { $$ = new Integer ($1.intValue () - $3.intValue ());  }
+| exp '*' exp        { $$ = new Integer ($1.intValue () * $3.intValue ());  }
+| exp '/' exp        { $$ = new Integer ($1.intValue () / $3.intValue ());  }
+| '-' exp  %prec NEG { $$ = new Integer (-$2.intValue ());                  }
+| exp '^' exp        { $$ = new Integer ((int)
+                                         Math.pow ($1.intValue (),
+                                                   $3.intValue ()));        }
+| '(' exp ')'        { $$ = $2;                                             }
+| '(' error ')'      { $$ = new Integer (1111);                             }
+| '!'                { $$ = new Integer (0); return YYERROR;                }
+| '-' error          { $$ = new Integer (0); return YYERROR;                }
+;
+
+
+%%
+class CalcLexer implements Calc.Lexer {
+
+  StreamTokenizer st;
+
+  public CalcLexer (InputStream is)
+  {
+    st = new StreamTokenizer (new InputStreamReader (is));
+    st.resetSyntax ();
+    st.eolIsSignificant (true);
+    st.whitespaceChars (9, 9);
+    st.whitespaceChars (32, 32);
+    st.wordChars (48, 57);
+  }
+
+
+  Position yypos = new Position (1, 0);
+
+  public Position getStartPos () {
+    return yypos;
+  }
+
+  public Position getEndPos () {
+    return yypos;
+  }
+
+  public void yyerror (Calc.Location l, String s)
+  {
+    if (l == null)
+      System.err.println (s);
+    else
+      System.err.println (l + ": " + s);
+  }
+
+
+  Integer yylval;
+
+  public Object getLVal () {
+    return yylval;
+  }
+
+  public int yylex () throws IOException {
+    int ttype = st.nextToken ();
+    yypos = new Position (yypos.lineno (), yypos.token () + 1);
+    if (ttype == st.TT_EOF)
+      return EOF;
+    else if (ttype == st.TT_EOL)
+      {
+        yypos = new Position (yypos.lineno () + 1, 0);
+        return (int) '\n';
+      }
+    else if (ttype == st.TT_WORD)
+      {
+        yylval = new Integer (st.sval);
+        return NUM;
+      }
+    else
+      return st.ttype;
+  }
+}
+
+
+class Position {
+  public int line;
+  public int token;
+
+  public Position ()
+  {
+    line = 0;
+    token = 0;
+  }
+
+  public Position (int l, int t)
+  {
+    line = l;
+    token = t;
+  }
+
+  public boolean equals (Position l)
+  {
+    return l.line == line && l.token == token;
+  }
+
+  public String toString ()
+  {
+    return Integer.toString (line) + "." + Integer.toString(token);
+  }
+
+  public int lineno ()
+  {
+    return line;
+  }
+
+  public int token ()
+  {
+    return token;
+  }
+}
diff --git a/examples/java/local.mk b/examples/java/local.mk
new file mode 100644
index 00000000..56e71630
--- /dev/null
+++ b/examples/java/local.mk
@@ -0,0 +1,34 @@
+## Copyright (C) 2018 Free Software Foundation, Inc.
+##
+## This program is free software: you can redistribute it and/or modify
+## it under the terms of the GNU General Public License as published by
+## the Free Software Foundation, either version 3 of the License, or
+## (at your option) any later version.
+##
+## This program is distributed in the hope that it will be useful,
+## but WITHOUT ANY WARRANTY; without even the implied warranty of
+## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+## GNU General Public License for more details.
+##
+## You should have received a copy of the GNU General Public License
+## along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+javadir = $(docdir)/%D%
+
+## ------ ##
+## Calc.  ##
+## ------ ##
+
+if ENABLE_JAVA
+  check_SCRIPTS += %D%/Calc.class
+  TESTS += %D%/Calc.test
+endif
+
+%D%/Calc.java: %D%/Calc.y $(BISON_IN) $(dist_pkgdata_DATA)
+	$(AM_V_GEN)$(BISON) $< -o $@
+
+%D%/Calc.class: %D%/Calc.java
+	$(AM_V_GEN) $(SHELL) $(top_builddir)/javacomp.sh $<
+
+dist_java_DATA = %D%/Calc.y
+CLEANFILES += %D%/Calc.class %D%/Calc.java
diff --git a/examples/local.mk b/examples/local.mk
index 6db28dce..4763221d 100644
--- a/examples/local.mk
+++ b/examples/local.mk
@@ -77,5 +77,6 @@ CLEANDIRS += %D%/*.dSYM
 
 include %D%/calc++/local.mk
 include %D%/c++/local.mk
+include %D%/java/local.mk
 include %D%/mfcalc/local.mk
 include %D%/rpcalc/local.mk
diff --git a/examples/test b/examples/test
index 96db4e7f..d9177cb1 100755
--- a/examples/test
+++ b/examples/test
@@ -33,6 +33,10 @@ do
     if test -x "$p"; then
         prog=$p
         break
+    elif test -f "$p.class"; then
+        pwd
+        prog="$SHELL $cwd/javaexec.sh -cp $(dirname $p) $(basename $p)"
+        break
     fi
 done
 if test x"$prog" = x; then
@@ -82,10 +86,12 @@ run ()
       echo "$me: PASS: $number"
     else
       echo "$me: FAIL: $number (expected output: $out_exp, effective: $out_eff)"
+      cat err_eff
       exit=false
     fi
   else
     echo "$me: FAIL: $number (expected status: $sta_exp, effective: $sta_eff)"
+    cat err_eff
     exit=false
   fi
   number=$(expr $number + 1)
diff --git a/tests/local.mk b/tests/local.mk
index e2245dab..497c7dc8 100644
--- a/tests/local.mk
+++ b/tests/local.mk
@@ -85,7 +85,7 @@ $(TESTSUITE): $(TESTSUITE_AT)
 
 # Move into %D%/ so that testsuite.dir etc. be created there.
 RUN_TESTSUITE = $(TESTSUITE) -C %D% $(TESTSUITEFLAGS)
-check_SCRIPTS = $(BISON) %D%/atconfig %D%/atlocal
+check_SCRIPTS += $(BISON) %D%/atconfig %D%/atlocal
 RUN_TESTSUITE_deps = all $(TESTSUITE) $(check_SCRIPTS)
 
 clean-local: clean-local-tests