## The challenge#

Write a function that converts an input string contains a `hex` value, and return a `decimal`.

## Test cases#

``````import org.junit.Test;
import static org.junit.Assert.*;

public class ExampleTests {

@Test
public void examples() {
// assertEquals("expected", "actual");
assertEquals(1, ConvertHexToDec.hexToDec("1"));
assertEquals(10, ConvertHexToDec.hexToDec("a"));
assertEquals(16, ConvertHexToDec.hexToDec("10"));
assertEquals(255, ConvertHexToDec.hexToDec("FF"));
assertEquals(-12, ConvertHexToDec.hexToDec("-C"));
}

}
``````

## The solution in Java#

In Java, it is really easy to convert Hex to Decimal.

You simply use the `Integer` class and call the `parseInt` method, making sure to also provide the base that you want to convert from.

As we know that the input will be a hex value, and we also know that the hexadecimal number system is a base 16 numbering system, we are able to do the following:

``````public class ConvertHexToDec {

public static int hexToDec(final String hexString) {
return Integer.parseInt(hexString, 16);
}

}
``````