sentence lookup API from Java

src/runtime/java/jpgf.c

@@ -651,6 +651,34 @@ Java_org_grammaticalframework_pgf_Completer_complete(JNIEnv* env, jclass clazz,
 	return jtokiter;
 }
 
+JNIEXPORT jobject JNICALL
+Java_org_grammaticalframework_pgf_SentenceExtractor_lookupSentence
+  (JNIEnv* env, jclass clazz, jobject jconcr, jstring jstartCat, jstring js, jobject jpool)
+{
+	GuPool* pool = get_ref(env, jpool);
+	GuPool* out_pool = gu_new_pool();
+
+    GuString startCat = j2gu_string(env, jstartCat, pool);
+    GuString s = j2gu_string(env, js, pool);
+
+	PgfType* type = gu_new_flex(pool, PgfType, exprs, 0);
+	type->hypos   = gu_empty_seq();
+	type->cid     = startCat;
+	type->n_exprs = 0;
+
+	GuEnum* res =
+		pgf_lookup_sentence(get_ref(env, jconcr), type, s, pool, out_pool);
+
+	jfieldID refId = (*env)->GetFieldID(env, (*env)->GetObjectClass(env, jconcr), "gr", "Lorg/grammaticalframework/pgf/PGF;");
+	jobject jpgf = (*env)->GetObjectField(env, jconcr, refId);
+
+	jclass expiter_class = (*env)->FindClass(env, "org/grammaticalframework/pgf/ExprIterator");
+	jmethodID constrId = (*env)->GetMethodID(env, expiter_class, "<init>", "(Lorg/grammaticalframework/pgf/PGF;Lorg/grammaticalframework/pgf/Pool;JJ)V");
+	jobject jexpiter = (*env)->NewObject(env, expiter_class, constrId, jpgf, jpool, p2l(out_pool), p2l(res));
+
+	return jexpiter;
+}
+
 JNIEXPORT jobject JNICALL 
 Java_org_grammaticalframework_pgf_TokenIterator_fetchTokenProb(JNIEnv* env, jclass clazz, jlong enumRef, jobject jpool)
 {
@@ -669,11 +697,12 @@ Java_org_grammaticalframework_pgf_TokenIterator_fetchTokenProb(JNIEnv* env, jcla
 
 JNIEXPORT jobject JNICALL 
 Java_org_grammaticalframework_pgf_ExprIterator_fetchExprProb
-  (JNIEnv* env, jclass clazz, jlong enumRef, jobject pool, jobject gr)
+  (JNIEnv* env, jclass clazz, jlong enumRef, jobject jpool, jobject gr)
 {
 	GuEnum* res = (GuEnum*) l2p(enumRef);
+	GuPool* pool = get_ref(env, jpool);
 
-	PgfExprProb* ep = gu_next(res, PgfExprProb*, NULL);
+	PgfExprProb* ep = gu_next(res, PgfExprProb*, pool);
 	if (ep == NULL)
 		return NULL;
 

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

@@ -39,6 +39,10 @@ public class Concr {
 		return new Completer(this, startCat, s, prefix);
 	}
 
+	public Iterable<ExprProb> lookupSentence(String startCat, String s) {
+		return new SentenceExtractor(this, startCat, s);
+	}
+
 	/** Computes the linearization of the abstract expression. */
 	public native String linearize(Expr expr);
 

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

@@ -0,0 +1,39 @@
+package org.grammaticalframework.pgf;
+
+import java.util.*;
+
+class SentenceExtractor implements Iterable<ExprProb> {
+	private Concr concr;
+	private String s;
+	private String startCat;
+	private double heuristics;
+	private Map<String,LiteralCallback> callbacks;
+	private ExprIterator iter;
+
+	public SentenceExtractor(Concr concr, String startCat, String s) {
+		this.concr    = concr;
+		this.startCat = startCat;
+		this.s        = s;
+		this.iter     = doExtract();
+	}
+
+	public Iterator<ExprProb> iterator() {
+		if (iter == null) {
+			// If someone has asked for a second iterator over
+			// the same parse results then we have to parse again.
+			return doExtract();
+		} else {
+			ExprIterator tmp_iter = iter;
+			iter = null;
+			return tmp_iter;
+		}
+	}
+
+	private ExprIterator doExtract()
+	{
+		Pool pool = new Pool();
+		return lookupSentence(concr, startCat, s, pool);
+	}
+
+	static native ExprIterator lookupSentence(Concr concr, String startCat, String s, Pool pool);
+}