+ /*
+ public static class JavaGrammar extends MetaGrammar {
+ public Object convertLabel(String label) { return new ClassMark(label); }
+ public Object convertFieldLabel(String label) { return new FieldMark(label); }
+
+ private static class FieldMark {
+ public final String field;
+ public FieldMark(String field) { this.field = field; }
+ public String toString() { return "."+field; }
+ }
+ private static class ClassMark {
+ public final String clazz;
+ public ClassMark(String clazz) { this.clazz = clazz; }
+ public String toString() { return clazz+"$"; }
+ }
+
+ public static Object build(Tree<Object> t, Class c) throws Exception {
+ System.out.println("** build " + c.getName() + " " + t.toPrettyString());
+ Object h = t.head();
+ if (h instanceof ClassMark) return build2(t, Class.forName(JavaGrammar.class.getName()+"$"+((ClassMark)h).clazz));
+ Object o = null;
+ if (t.numChildren()==0) o = t.head();
+ else if (t.head()==null) return build2(t, c);
+ else if (t.head() instanceof FieldMark) {
+ return build2(new Tree(null, new Tree[] { t }), c);
+ } else {
+ throw new Exception("don't know how to cope: " + c.getName() + " <- " + t.toPrettyString());
+ }
+ return Reflection.rebuild(o, c);
+ }
+ private static Object build2(Tree<Object> t, Class c) throws Exception {
+ System.out.println("** build2 " + c.getName() + " " + t.toPrettyString());
+ if (!Reflection.isConcrete(c)) {
+ Field f = c.getField("subclasses");
+ if (f==null) throw new Exception("don't know how to cope: " + c.getName() + " <- " + t.toPrettyString());
+ Class[] subs = (Class[])f.get(null);
+ OUTER: for(int i=0; i<subs.length; i++) {
+ for(Tree<Object> t2 : t) {
+ Object o2 = t2.head();
+ System.out.println("checking " + o2 + " in " + subs[i].getName());
+ if (o2 instanceof FieldMark) {
+ if (subs[i].getField(((FieldMark)o2).field)==null) continue OUTER;
+ }
+ }
+ c = subs[i];
+ break;
+ }
+ }
+ Object o = c.newInstance();
+ for(Tree<Object> t2 : t) {
+ Object o2 = t2.head();
+ if (o2 instanceof FieldMark) {
+ FieldMark f = (FieldMark)o2;
+ Field field = c.getField(ReflectiveWalker.mangle(f.field));
+ Object tgt = build(t2.child(0), field.getType());
+ System.out.println("setting " + f.field +
+ " on a " + o.getClass().getName() +
+ " to " + (tgt==null?"null":tgt.getClass().getName()));
+ field.set(o, tgt);
+ }
+ }
+ System.out.println("returning a " + o.getClass().getName());
+ return o;
+ }
+ public static Object build(Tree<Object> t) throws Exception {
+ Object h = t.head();
+ if (h instanceof ClassMark) {
+ ClassMark cm = (ClassMark)h;
+ Class c = Class.forName(JavaGrammar.class.getName() + "$" + ReflectiveWalker.mangle(cm.clazz));
+ return build2(t, c);
+ }
+
+ return h==null ? null : h.toString();
+ }
+
+ public static interface Expr {
+ public static Class[] subclasses = new Class[] { _plus_.class, num.class };
+ }
+ public static class _plus_ implements Expr {
+ public Expr left;
+ public Expr right;
+ public String toString() { return left + "+" + right; }
+ }
+ public static class num implements Expr {
+ public String val;
+ public String toString() { return "["+val+"]"; }
+ }