SimpleBindings containsKey() method in Java with Examples

The containsKey() method of SimpleBindings class is used to return true if this map which is backing this SimpleBindings object contains a mapping for the specified key. If SimpleBindings object contains this key then the method returns true else false.Â
Syntax:Â
public boolean containsKey(Object key)
Parameters: This method accepts only one parameters key which is key whose presence in this map is to be tested.Â
Return Value: This method returns true if this map contains a mapping for the specified key.Â
Exception: This method throws following exceptions:
- NullPointerException: if key is null
- ClassCastException: if key is not String
- IllegalArgumentException: if key is empty String
Java programs to Illustrate the working of containsKey() method:Â
Program 1:Â
Java
// Java program to demonstrate containsKey() methodÂ
import javax.script.SimpleBindings;Â
public class GFG {Â Â Â Â public static void main(String[] args)Â Â Â Â {Â
        // create simpleBindings object        SimpleBindings bindings = new SimpleBindings();Â
        // add some keys with values        bindings.put("key1", "value1");        bindings.put("key2", "value2");        bindings.put("key3", "value3");Â
        // check key2 is exists in bindings or not        boolean isKey2Exist = bindings.containsKey("key2");Â
        // print        System.out.println("Key2 exists:" + isKey2Exist);    }} |
Output:
key2 exists:true
Program 2:Â
Java
// Java program to demonstrate containsKey() methodÂ
import javax.script.SimpleBindings;Â
public class GFG {Â Â Â Â public static void main(String[] args)Â Â Â Â {Â
        // create simpleBindings object        SimpleBindings asiaTeamList            = new SimpleBindings();Â
        // add team in asiaTeamList        asiaTeamList.put("team1", "India");        asiaTeamList.put("team2", "Sri Lanka");        asiaTeamList.put("team3", "Pakistan");        asiaTeamList.put("team4", "Bangladesh");Â
        // check England exists in bindings or not        boolean isKey2Exist            = asiaTeamList.containsKey("England");Â
        // print        System.out.println("England exists in Asia Team:"                           + isKey2Exist);    }} |
Output:
England exists in Asia Team:false
References: https://docs.oracle.com/javase/10/docs/api/javax/script/SimpleBindings.html#containsKey(java.lang.Object)



