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/*******************************************************************************
* Copyright (c) 2008 IBM Corporation and others.
*
* This program and the accompanying materials
* are made available under the terms of the Eclipse Public License 2.0
* which accompanies this distribution, and is available at
* https://www.eclipse.org/legal/epl-2.0/
*
* SPDX-License-Identifier: EPL-2.0
*
* Contributors:
* IBM Corporation - initial API and implementation
*******************************************************************************/
import java.util.*;
import java.util.Map.Entry;
/**
* Tests built in logical structures.
*/
public class LogicalStructures {
public static void main(String[] args) {
generateGarbage();
Map<String, Integer> map = new HashMap<>();
map.put("one", 1);
map.put("two", 2);
List<String> list = new ArrayList<>();
list.add("three");
list.add("four");
Set<Entry<String, Integer>> set = map.entrySet();
Map.Entry<String, Integer> entry = set.iterator().next();
entry.getKey();
}
private static void generateGarbage() {
// generate garbage repeatedly to verify that logical values don't get GCed
Timer timer = new Timer(true);
timer.scheduleAtFixedRate(new TimerTask() {
private List<String> garbage;
@Override
public void run() {
System.gc();
garbage = Arrays.asList(new String("a"), new String("b"), new String("c"));
}
}, 200, 20);
}
}
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