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Michael C Smith has worked in executive roles for two companies. From 2003 to present, they have been the President and CEO of Western Systems Inc., as well as the CEO and Owner. Prior to this, they were the Vice President and Co Owner of Advanced Traffic Products from 1993 to 2003.

Q: How to check if a key exists in a map

You can use the <code>map.containsKey()</code> method to check if a key exists in a map.

This method will return a boolean value indicating whether the specified key exists in the map or not.

For example:

<code>Map&lt;String, Integer&gt; myMap = new HashMap&lt;&gt;();

myMap.put("A", 1);

myMap.put("B", 2);

if (myMap.containsKey("A")) {

System.out.println("Key A exists in the map");

}

</code>