Java API for opening/closing SG databases

3 files changed, 56 insertions, 0 deletions

diff --git a/src/runtime/java/org/grammaticalframework/sg/SG.java b/src/runtime/java/org/grammaticalframework/sg/SG.java
new file mode 100644
index 000000000..631b38ff7
--- /dev/null
+++ b/src/runtime/java/org/grammaticalframework/sg/SG.java
@@ -0,0 +1,22 @@
+package org.grammaticalframework.sg;
+
+import java.io.Closeable;
+import org.grammaticalframework.pgf.Expr;
+
+public class SG implements Closeable {
+	public static native SG openSG(String path);
+	public native void close();
+	public native TripleResult queryTriple(Expr subj, Expr pred, Expr obj);
+
+	//////////////////////////////////////////////////////////////////
+	// private stuff
+	private long ref;
+
+	private SG(long ref) {
+		this.ref  = ref;
+	}
+
+	static {
+		System.loadLibrary("jpgf");
+	}
+}
diff --git a/src/runtime/java/org/grammaticalframework/sg/SGError.java b/src/runtime/java/org/grammaticalframework/sg/SGError.java
new file mode 100644
index 000000000..0de876bd4
--- /dev/null
+++ b/src/runtime/java/org/grammaticalframework/sg/SGError.java
@@ -0,0 +1,9 @@
+package org.grammaticalframework.sg;
+
+public class SGError extends RuntimeException {
+	private static final long serialVersionUID = -6098784400143861939L;
+
+	public SGError(String message) {
+		super(message);
+	}
+}
diff --git a/src/runtime/java/org/grammaticalframework/sg/TripleResult.java b/src/runtime/java/org/grammaticalframework/sg/TripleResult.java
new file mode 100644
index 000000000..59a0ddb81
--- /dev/null
+++ b/src/runtime/java/org/grammaticalframework/sg/TripleResult.java
@@ -0,0 +1,25 @@
+package org.grammaticalframework.sg;
+
+import java.io.Closeable;
+import org.grammaticalframework.pgf.Expr;
+
+public class TripleResult implements Closeable {
+	private Expr subj;
+	private Expr pred;
+	private Expr obj;
+
+	public native boolean hasNext();
+	public native void close();
+	
+	public Expr getSubject() {
+		return subj;
+	}
+
+	public Expr getPredicate() {
+		return pred;
+	}
+
+	public Expr getObject() {
+		return obj;
+	}
+}