import java.io.File;
import java.io.IOException;
import java.net.URI;
+import java.util.ArrayList;
import java.util.Collection;
import java.util.HashMap;
import java.util.HashSet;
@Override
public void close() {
synchronized (managers) {
- for (var m : managers) {
+ for (var m : new ArrayList<>(managers)) {
try {
m.close();
} catch (IOException e) {