Package SQLite

Interface Function

public interface Function
Callback interface for SQLite's user defined functions. Each callback method receives a FunctionContext object which is used to set the function result or error code.

Example:
   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);

  • Method Details

    • function

      void function​(FunctionContext fc, String[] args)
      Callback for regular function.
      Parameters:
      fc - function's context for reporting result
      args - String array of arguments

    • step

      void step​(FunctionContext fc, String[] args)
      Callback for one step in aggregate function.
      Parameters:
      fc - function's context for reporting result
      args - String array of arguments

    • last_step

      void last_step​(FunctionContext fc)
      Callback for final step in aggregate function.
      Parameters:
      fc - function's context for reporting result