an initial Java/C API for predicting literals. Still not utilized

src/runtime/c/pgf/literals.c

@@ -48,8 +48,25 @@ pgf_match_string_lit(PgfLiteralCallback* self,
 	}
 }
 
+static void
+pgf_predict_empty_next(GuEnum* self, void* to, GuPool* pool)
+{
+	*((PgfTokenProb**) to) = NULL;
+}
+
+static GuEnum*
+pgf_predict_empty(PgfLiteralCallback* self,
+	              size_t lin_idx,
+	              GuString prefix,
+	              GuPool *out_pool)
+{
+	GuEnum* en = gu_new(GuEnum, out_pool);
+	en->next = pgf_predict_empty_next;
+	return en;
+}
+
 static PgfLiteralCallback pgf_string_literal_callback =
-  { pgf_match_string_lit } ;
+  { pgf_match_string_lit, pgf_predict_empty } ;
 
 
 
@@ -101,7 +118,7 @@ pgf_match_int_lit(PgfLiteralCallback* self,
 }
 
 static PgfLiteralCallback pgf_int_literal_callback =
-  { pgf_match_int_lit } ;
+  { pgf_match_int_lit, pgf_predict_empty } ;
 
 
 
@@ -153,7 +170,7 @@ pgf_match_float_lit(PgfLiteralCallback* self,
 }
 
 static PgfLiteralCallback pgf_float_literal_callback =
-  { pgf_match_float_lit } ;
+  { pgf_match_float_lit, pgf_predict_empty } ;
 
 
 
@@ -231,7 +248,7 @@ pgf_match_name_lit(PgfLiteralCallback* self,
 }
 
 PgfLiteralCallback pgf_nerc_literal_callback =
-  { pgf_match_name_lit } ;
+  { pgf_match_name_lit, pgf_predict_empty } ;
 
 
 PgfCallbacksMap*

src/runtime/c/pgf/pgf.h

@@ -161,6 +161,10 @@ struct PgfLiteralCallback {
 	                      size_t lin_idx,
 	                      GuString sentence, size_t* poffset,
 	                      GuPool *out_pool);
+    GuEnum*    (*predict)(PgfLiteralCallback* self,
+	                      size_t lin_idx,
+	                      GuString prefix,
+	                      GuPool *out_pool);
 };
 
 void

src/runtime/java/jpgf.c

@@ -713,19 +713,26 @@ typedef struct {
 	PgfLiteralCallback callback;
 	jobject jcallback;
 	jmethodID match_methodId;
+	jmethodID predict_methodId;
 	GuFinalizer fin;
 } JPgfLiteralCallback;
 
-static PgfExprProb* 
-jpgf_literal_callback_fn(PgfLiteralCallback* self,
-                         size_t lin_idx,
-                         GuString sentence, size_t* poffset,
-                         GuPool *out_pool)
+typedef struct {
+	GuEnum en;
+	jobject jiterator;
+	GuFinalizer fin;
+} JPgfTokenProbEnum;
+
+static PgfExprProb*
+jpgf_literal_callback_match(PgfLiteralCallback* self,
+                            size_t lin_idx,
+                            GuString sentence, size_t* poffset,
+                            GuPool *out_pool)
 {
 	JPgfLiteralCallback* callback = gu_container(self, JPgfLiteralCallback, callback);
 
 	JNIEnv *env;
-    (*cachedJVM)->AttachCurrentThread(cachedJVM, (void **)&env, NULL);
+    (*cachedJVM)->AttachCurrentThread(cachedJVM, &env, NULL);
 
 	jstring jsentence = gu2j_string(env, sentence);
 	jobject result = (*env)->CallObjectMethod(env, callback->jcallback, callback->match_methodId, lin_idx, jsentence, *poffset);
@@ -782,13 +789,50 @@ jpgf_literal_callback_fn(PgfLiteralCallback* self,
 	return ep;
 }
 
+static void 
+jpgf_token_prob_enum_fin(GuFinalizer* self)
+{
+	JPgfTokenProbEnum* en = gu_container(self, JPgfTokenProbEnum, fin);
+	
+	JNIEnv *env;
+    (*cachedJVM)->AttachCurrentThread(cachedJVM, &env, NULL);
+
+	(*env)->DeleteGlobalRef(env, en->jiterator);
+}
+
+static GuEnum*
+jpgf_literal_callback_predict(PgfLiteralCallback* self,
+	                          size_t lin_idx,
+	                          GuString prefix,
+	                          GuPool *out_pool)
+{
+	JPgfLiteralCallback* callback = gu_container(self, JPgfLiteralCallback, callback);
+
+	JNIEnv *env;
+    (*cachedJVM)->AttachCurrentThread(cachedJVM, &env, NULL);
+
+	jstring jprefix = gu2j_string(env, prefix);
+	jobject jiterator = (*env)->CallObjectMethod(env, callback->jcallback, callback->predict_methodId, lin_idx, jprefix);
+	if (jiterator == NULL)
+		return NULL;
+
+	JPgfTokenProbEnum* en = gu_new(JPgfTokenProbEnum, out_pool);
+	en->en.next = NULL;
+	en->jiterator = (*env)->NewGlobalRef(env, jiterator);
+	en->fin.fn = jpgf_token_prob_enum_fin;
+
+	gu_pool_finally(out_pool, &en->fin);
+
+	return &en->en;
+}
+
 static void 
 jpgf_literal_callback_fin(GuFinalizer* self)
 {
 	JPgfLiteralCallback* callback = gu_container(self, JPgfLiteralCallback, fin);
 	
 	JNIEnv *env;
-    (*cachedJVM)->AttachCurrentThread(cachedJVM, (void **)&env, NULL);
+    (*cachedJVM)->AttachCurrentThread(cachedJVM, &env, NULL);
 
 	(*env)->DeleteGlobalRef(env, callback->jcallback);
 }
@@ -800,12 +844,14 @@ Java_org_grammaticalframework_pgf_Concr_addLiteral(JNIEnv* env, jobject self, js
 	GuPool* pool = pgf_concr_get_pool(concr);
 	
 	JPgfLiteralCallback* callback = gu_new(JPgfLiteralCallback, pool);
-	callback->callback.match = jpgf_literal_callback_fn;
+	callback->callback.match   = jpgf_literal_callback_match;
+	callback->callback.predict = jpgf_literal_callback_predict;
 	callback->jcallback = (*env)->NewGlobalRef(env, jcallback);
 	callback->fin.fn = jpgf_literal_callback_fin;
 
 	jclass callback_class = (*env)->GetObjectClass(env, jcallback);
 	callback->match_methodId = (*env)->GetMethodID(env, callback_class, "match", "(ILjava/lang/String;I)Lorg/grammaticalframework/pgf/LiteralCallback$CallbackResult;");
+	callback->predict_methodId = (*env)->GetMethodID(env, callback_class, "predict", "(ILjava/lang/String;)Ljava/util/Iterator;");
 
 	gu_pool_finally(pool, &callback->fin);
 	

src/runtime/java/org/grammaticalframework/pgf/LiteralCallback.java

@@ -1,8 +1,12 @@
 package org.grammaticalframework.pgf;
 
+import java.util.Iterator;
+
 public interface LiteralCallback {
 	public CallbackResult match(int lin_idx, String sentence, int start_offset);
-	
+
+	public Iterator<TokenProb> predict(int lin_idx, String prefix);
+
 	public static class CallbackResult {
 		private ExprProb ep;
 		private int offset;

src/runtime/java/org/grammaticalframework/pgf/NercLiteralCallback.java

@@ -1,5 +1,8 @@
 package org.grammaticalframework.pgf;
 
+import java.util.Collections;
+import java.util.Iterator;
+
 public class NercLiteralCallback implements LiteralCallback {
 	public CallbackResult match(int lin_idx, String sentence, int offset) {
 		StringBuilder sbuilder = new StringBuilder();
@@ -33,4 +36,8 @@ public class NercLiteralCallback implements LiteralCallback {
 
 		return null;
 	}
+	
+	public Iterator<TokenProb> predict(int lin_idx, String prefix) {
+		return Collections.<TokenProb>emptyList().iterator();
+	}
 }