out-of-memory

I have written a code and I run it a lot but suddenly I got an OutOfMemoryError: Exception in thread “main” java.lang.OutOfMemoryError: Java heap space at javax.media.j3d.BoundingBox.<init>(BoundingBox.java:86) at javax.media.j3d.NodeRetained.<init>(NodeRetained.java:198) at javax.media.j3d.LeafRetained.<init>(LeafRetained.java:40) at javax.media.j3d.LightRetained.<init>(LightRetained.java:44) at javax.media.j3d.DirectionalLightRetained.<init>(DirectionalLightRetained.java:50) at javax.media.j3d.DirectionalLight.createRetained(DirectionalLight.java:116) at javax.media.j3d.SceneGraphObject.<init>(SceneGraphObject.java:119) at javax.media.j3d.Node.<init>(Node.java:178) at javax.media.j3d.Leaf.<init>(Leaf.java:50) at javax.media.j3d.Light.<init>(Light.java:270) at javax.media.j3d.DirectionalLight.<init>(DirectionalLight.java:87)