Why does `toArray()` in Java Throw a `ClassCastException` when Converting to a String Array?

String[] toArray() in Java Throws ClassCastException

When attempting to use (String[])List.toArray() in Java, users may encounter a ClassCastException. This occurs because the toArray() method returns an Object[], which cannot be directly cast to a String[] even if the contents are strings.

The confusion stems from the fact that the Java compiler, before compiling, performs type erasure on generic types. This means that at runtime, a List<String> will be represented as a List with no type information. Consequently, the toArray() method has no knowledge of the underlying data type, resulting in an Object[] being returned.

To avoid the exception, developers should explicitly specify the type of array they want. This can be done using the following syntax:

<code class="java">String[] v3 = (String[])v2.toArray(new String[v2.size()]);</code>

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