// This example illustrates the manipulation of C++ references in Java. public class runme { static { try { System.loadLibrary("example"); } catch (UnsatisfiedLinkError e) { System.err.println("Native code library failed to load. See the chapter on Dynamic Linking Problems in the SWIG Java documentation for help.\n" + e); System.exit(1); } } public static void main(String argv[]) { System.out.println( "Creating some objects:" ); Vector a = new Vector(3,4,5); Vector b = new Vector(10,11,12); System.out.println( " Created " + a.print() ); System.out.println( " Created " + b.print() ); // ----- Call an overloaded operator ----- // This calls the wrapper we placed around // // operator+(const Vector &a, const Vector &) // // It returns a new allocated object. System.out.println( "Adding a+b" ); Vector c = example.addv(a,b); System.out.println( " a+b = " + c.print() ); // Note: Unless we free the result, a memory leak will occur if the -noproxy commandline // is used as the proxy classes define finalizers which call the delete() method. When // -noproxy is not specified the memory management is controlled by the garbage collector. // You can still call delete(). It will free the c++ memory immediately, but not the // Java memory! You then must be careful not to call any member functions as it will // use a NULL c pointer on the underlying c++ object. We set the Java object to null // which will then throw a Java exception should we attempt to use it again. c.delete(); c = null; // ----- Create a vector array ----- System.out.println( "Creating an array of vectors" ); VectorArray va = new VectorArray(10); System.out.println( " va = " + va.toString() ); // ----- Set some values in the array ----- // These operators copy the value of Vector a and Vector b to the vector array va.set(0,a); va.set(1,b); // This works, but it would cause a memory leak if -noproxy was used! va.set(2,example.addv(a,b)); // Get some values from the array System.out.println( "Getting some array values" ); for (int i=0; i<5; i++) System.out.println( " va(" + i + ") = " + va.get(i).print() ); // Watch under resource meter to check on this System.out.println( "Making sure we don't leak memory." ); for (int i=0; i<1000000; i++) c = va.get(i%10); // ----- Clean up ----- // This could be omitted. The garbage collector would then clean up for us. System.out.println( "Cleaning up" ); va.delete(); a.delete(); b.delete(); } }