## Config Protector
### Instructions
Create a class `ConfigProtector` that provides a method to hide sensitive data in a configuration file using `Regex` . The method should replace sensitive values with asterisks. The configuration file will be provided as a `String` , and the keys for the sensitive data will be given in a `List` .
The config file format will always be as follows:
```
username=admin
npassword=secret
...
```
### Expected Class
```java
import java.util.List;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
public class ConfigProtector {
public String hideSensitiveData(String configFile, List< String > sensitiveKeys) {
// Implementation to hide sensitive data in the configuration file using regex
}
}
```
### Usage
Here is a possible `ExerciseRunner.java` to test your class:
```java
import java.util.List;
import java.util.Arrays;
public class ExerciseRunner {
public static void main(String[] args) {
ConfigProtector protector = new ConfigProtector();
String configFile1 = "username=admin\npassword=secret\nhost=localhost\n";
List< String > sensitiveKeys1 = Arrays.asList("password");
System.out.println("Protected Config 1:\n" + protector.hideSensitiveData(configFile1, sensitiveKeys1));
String configFile2 = "apiKey=12345\napiSecret=abcdef\nendpoint=https://api.example.com\n";
List< String > sensitiveKeys2 = Arrays.asList("apiKey", "apiSecret");
System.out.println("Protected Config 2:\n" + protector.hideSensitiveData(configFile2, sensitiveKeys2));
String configFile3 = "username=user\npassword=pass\n";
List< String > sensitiveKeys3 = Arrays.asList("username", "password");
System.out.println("Protected Config 3:\n" + protector.hideSensitiveData(configFile3, sensitiveKeys3));
}
}
```
### Expected Output
```shell
$ javac *.java -d build
$ java -cp build ExerciseRunner
Protected Config 1:
username=admin
password=******
host=localhost
Protected Config 2:
apiKey=*****
apiSecret=******
endpoint=https://api.example.com
Protected Config 3:
username=****
password=****
$
```
