Java IdentityHashMap .containsKey (Object key)
Syntax
IdentityHashMap.containsKey(Object key) has the following syntax.
public boolean containsKey(Object key)
Example
In the following code shows how to use IdentityHashMap.containsKey(Object key) method.
/* w w w . j a v a 2 s . c o m*/
import java.util.IdentityHashMap;
import java.util.Map;
public class Main {
public static void main(String[] argv) throws Exception {
Map<Object, Object> objMap = new IdentityHashMap<Object, Object>();
Object o1 = new Integer(123);
Object o2 = new Integer(123);
objMap.put(o1, "first");
objMap.put(o2, "from java2s.com");
Object v1 = objMap.get(o1);
System.out.println(v1);
Object v2 = objMap.get(o2);
System.out.println(v2);
// check if key 3 exists
boolean isavailable = objMap.containsKey(o1);
System.out.println(isavailable);
}
}
The code above generates the following result.
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