Android :: Unable To Access Android Assets

Using this code it should return a list of the assets. But it crashes, with a "Source not found, Edit Source Lookup Path..." message in the debugger when I call the list method:

@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);

AssetManager assets = this.getAssets();
try {
//error happens on this next line
String[] l = assets.list(null);
} catch (IOException e) {

}
}