Allow multi-destroy() (#139)

CHANGELOG.md

@@ -27,8 +27,10 @@
 ## 0.5.3 - unreleased
 - Fix INTERNAL ERROR in `FastLSolve.solveL1Straight()` caused by bug in `DLCP.solve1()`.
   [#133](https://github.com/tzaeschke/ode4j/issues/133)
-- Fix formatting of degub/info/error message.
+- Fix formatting of debug/info/error message.
   [#135](https://github.com/tzaeschke/ode4j/issues/135)
+- QOL: allow calling destroy() multiple times.
+  [#139](https://github.com/tzaeschke/ode4j/pull/139)
 
 ## 0.5.2 - 2023-10-07
 - Fix DVector3.cross() returning always 0. [#128](https://github.com/tzaeschke/ode4j/issues/128)

core/src/main/java/org/ode4j/ode/internal/DDestructible.java

@@ -65,11 +65,11 @@ protected DDestructible() {
 	 */
 	protected void DESTRUCTOR() {
 		if (isDestructed) {
-			System.err.println("WARNING Object was already destructed.");
-			new RuntimeException().printStackTrace();
+			//	System.err.println("WARNING Object was already destructed.");
+			//	new RuntimeException().printStackTrace();
+			ErrorHdl.dMessage(0, "WARNING Object was already destructed.");
 		}
 		isDestructed = true;
-		//System.err.println("CCC");
 	}
 
 

core/src/main/java/org/ode4j/ode/internal/DxBody.java

@@ -197,6 +197,10 @@ public static DxBody dBodyCreate (DxWorld w)
 	public void dBodyDestroy ()
 	{
 		//dAASSERT (b);
+		// ode4j special: We set world=null, so we can check here
+		if (world == null) {
+			return; // already destroyed
+		}
 
 		// all geoms that link to this body must be notified that the body is about
 		// to disappear. note that the call to dGeomSetBody(geom,0) will result in
@@ -223,6 +227,9 @@ public void dBodyDestroy ()
 		removeObjectFromList ();
 		world.nb--;
 
+		// ode4j special: We set world=null, so we can check precondition in destroy()
+		world = null;
+
 		// delete the average buffers
 		//TZ nothing to do
 		//			if(average_lvel_buffer!= null)

core/src/test/java/org/ode4j/ode/TestIssue0139_MultiDestroy.java

@@ -0,0 +1,77 @@
+/*************************************************************************
+ *                                                                       *
+ * Open Dynamics Engine 4J, Copyright (C) 2009-2014 Tilmann Zaeschke     *
+ * All rights reserved.  Email: [email protected]   Web: www.ode4j.org        *
+ *                                                                       *
+ * This library is free software; you can redistribute it and/or         *
+ * modify it under the terms of EITHER:                                  *
+ *   (1) The GNU Lesser General Public License as published by the Free  *
+ *       Software Foundation; either version 2.1 of the License, or (at  *
+ *       your option) any later version. The text of the GNU Lesser      *
+ *       General Public License is included with this library in the     *
+ *       file LICENSE.TXT.                                               *
+ *   (2) The BSD-style license that is included with this library in     *
+ *       the file ODE-LICENSE-BSD.TXT and ODE4J-LICENSE-BSD.TXT.         *
+ *                                                                       *
+ * This library is distributed in the hope that it will be useful,       *
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of        *
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the files    *
+ * LICENSE.TXT, ODE-LICENSE-BSD.TXT and ODE4J-LICENSE-BSD.TXT for more   *
+ * details.                                                              *
+ *                                                                       *
+ *************************************************************************/
+package org.ode4j.ode;
+
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+
+/**
+ * Issue #133: ODE INTERNAL ERROR in FastLSolve.solveL1Straight().
+ */
+public class TestIssue0139_MultiDestroy {
+
+    private final DContactBuffer contacts = new DContactBuffer(4);
+    private DWorld world;
+    private DJointGroup contactGroup;
+
+    @Before
+    public void beforeTest() {
+        OdeHelper.initODE2(0);
+    }
+
+    @After
+    public void afterTest() {
+        OdeHelper.closeODE();
+    }
+
+    @Test
+    public void test() {
+        double ballRadius = 5.0;
+        double ballMass = 23.0;
+        contactGroup = OdeHelper.createJointGroup();
+        world = OdeHelper.createWorld();
+        world.setGravity(0, 0, -9.81);
+        DSpace space = OdeHelper.createSimpleSpace();
+        DBody ballBody = OdeHelper.createBody(world);
+        DGeom ballGeom = OdeHelper.createSphere(space, ballRadius);
+        ballGeom.setBody(ballBody);
+        DMass m = OdeHelper.createMass();
+        m.setSphereTotal(ballMass, ballRadius);
+        ballBody.setMass(m);
+        DPlane plane = OdeHelper.createPlane(space, 0, 0, 1, 0);
+
+        plane.destroy();
+        space.destroy();
+        world.destroy();
+        ballBody.destroy();
+        ballGeom.destroy();
+
+        // Test duplicate calls to destroy()
+        plane.destroy();
+        space.destroy();
+        world.destroy();
+        ballBody.destroy();
+        ballGeom.destroy();
+    }
+}