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
// Java program to demonstrate containsKey() methodimport 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 exists:" + isKey2Exist); }} |
Output:
key2 exists:true
Program 2:
Java
// Java program to demonstrate containsKey() methodimport 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 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)
