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.
Syntax:
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.
Return Value: This method returns true if this map contains a mapping for the specified key.
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:
Program 1:
// Java program to demonstrate containsKey() method import javax.script.SimpleBindings; public class GFG { public static void main(String[] args) { // create simpleBindings object SimpleBindings bindings = new SimpleBindings(); // add some keys with values bindings.put( "key1" , "value1" ); bindings.put( "key2" , "value2" ); bindings.put( "key3" , "value3" ); // check key2 is exists in bindings or not boolean isKey2Exist = bindings.containsKey( "key2" ); // print System.out.println( "Key2 exits:" + isKey2Exist); } } |
Key2 exits:true
Program 2:
// Java program to demonstrate containsKey() method import javax.script.SimpleBindings; public class GFG { public static void main(String[] args) { // create simpleBindings object SimpleBindings asiaTeamList = new SimpleBindings(); // add team in asiaTeamList asiaTeamList.put( "team1" , "India" ); asiaTeamList.put( "team2" , "Sri Lanka" ); asiaTeamList.put( "team3" , "Pakistan" ); asiaTeamList.put( "team4" , "Bangladesh" ); // check England exists in bindings or not boolean isKey2Exist = asiaTeamList.containsKey( "England" ); // print System.out.println( "England exits in Asia Team:" + isKey2Exist); } } |
England exits in Asia Team:false
References: https://docs.oracle.com/javase/10/docs/api/javax/script/SimpleBindings.html#containsKey(java.lang.Object)
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