清除哈希表中的所有元素

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/*
Remove all values from Java HashMap example
This Java Example shows how to remove all values from HashMap object or empty
HashMap or clear HashMap using clear method.
*/
import java.util.HashMap;
public class EmptyHashMapExample {
public static void main(String[] args) {
// create HashMap object
HashMap hMap = new HashMap();
// add key value pairs to HashMap
hMap.put("1", "One");
hMap.put("2", "Two");
hMap.put("3", "Three");
/*
* To remove all values or clear HashMap use void clear method() of
* HashMap class. Clear method removes all key value pairs contained in
* HashMap.
*/
hMap.clear();
System.out.println("Total key value pairs in HashMap are : "
+ hMap.size());
}
}
/*
* Output would be Total key value pairs in HashMap are : 0
*/