1 files changed, 59 insertions, 0 deletions
diff --git a/sqlite-jdbc/src/main/java/SQLite/Function.java b/sqlite-jdbc/src/main/java/SQLite/Function.java
new file mode 100644
index 0000000..5aa5e33
--- /dev/null
+++ b/sqlite-jdbc/src/main/java/SQLite/Function.java
@@ -0,0 +1,59 @@
+package SQLite;
+
+/**
+ * Callback interface for SQLite's user defined functions.
+ * Each callback method receives a
+ * <A HREF="FunctionContext.html">FunctionContext</A> object
+ * which is used to set the function result or error code.
+ * <BR><BR>
+ * Example:<BR>
+ *
+ * <PRE>
+ *   class SinFunc implements SQLite.Function {
+ *     public void function(SQLite.FunctionContext fc, String args[]) {
+ *       try {
+ *         Double d = new Double(args[0]);
+ *         fc.set_result(Math.sin(d.doubleValue()));
+ *       } catch (Exception e) {
+ *         fc.set_error("sin(" + args[0] + "):" + e);
+ *       }
+ *     }
+ *     ...
+ *   }
+ *   SQLite.Database db = new SQLite.Database();
+ *   db.open("db", 0);
+ *   db.create_function("sin", 1, SinFunc);
+ *   ...
+ *   db.exec("select sin(1.0) from test", null);
+ * </PRE>
+ */
+
+public interface Function {
+
+    /**
+     * Callback for regular function.
+     *
+     * @param fc function's context for reporting result
+     * @param args String array of arguments
+     */
+
+    public void function(FunctionContext fc, String args[]);
+
+    /**
+     * Callback for one step in aggregate function.
+     *
+     * @param fc function's context for reporting result
+     * @param args String array of arguments
+     */
+
+    public void step(FunctionContext fc, String args[]);
+
+    /**
+     * Callback for final step in aggregate function.
+     *
+     * @param fc function's context for reporting result
+     */
+
+    public void last_step(FunctionContext fc);
+
+}