对同一个map取keySet()得到的结果相同,用equals和==得到的都是true
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*/
package map;
import java.util.LinkedHashMap;
import java.util.Set;
/**
*对同一个map取keySet()得到的结果相同,用equals和==得到的都是true
* @author Jq
*/
public class MapTestMain {
private void mapTest() {
LinkedHashMap<Integer, String> testMap = new LinkedHashMap<>();
testMap.put(1, "one");
testMap.put(2, "two");
testMap.put(3, "three");
Set keySet_1 = testMap.keySet();
Set keySet_2 = testMap.keySet();
System.out.println("Equals:" + keySet_1.equals(keySet_2));
System.out.println("==: " + (keySet_1 == keySet_2));
}
/**
* @param args the command line arguments
*/
public static void main(String[] args) {
MapTestMain test = new MapTestMain();
test.mapTest();
}
}