What is SuppressWarnings ("unchecked") in Java?

@SuppressWarnings("unchecked") is an annotation in Java that tells the compiler to suppress specific warnings that are generated during the compilation of the code.

The unchecked warning is issued by the compiler when a type safety check has been suppressed, typically using an @SuppressWarnings("unchecked") annotation or by using a raw type in a parameterized type.

For example, consider the following code:

List list = new ArrayList();
list.add("A");
list.add(1);

@SuppressWarnings("unchecked")
List<String> list2 = list;

In this example, the compiler will issue an unchecked warning because the elements of the list are not checked for type safety when they are added to the list2 variable. The @SuppressWarnings("unchecked") annotation is used to suppress this warning.

The @SuppressWarnings annotation should be used with caution, as it can mask potential problems in the code. It is generally a good idea to fix the underlying issue that is causing the warning, rather than suppressing the warning.