BetterNamingAndSomeRefactoring.java

//
// CHALLENGE (work in pairs):
// Move from f(o) -> o.f() and sure that the code is CQS compliant.
//


// 1
class CsvParser<T extends Lines> { 
    Collection<T> parse(File location) { 
    } 
} 


// 2
interface Pinger { 
    void sendPing(); 
}


// 3
interface TcpSocket { 
    Stream<Byte> startReading(); 
} 

// 4 
// Make me CQS friendly!
interface Input {
  boolean validate();
}

// 5
// Iovation - a company that maintains a blacklist of email addresses and corresponding IPs
interface IovationService { 
    boolean shouldBlockWebsiteVisitor(IovationClientRequest request); 
} 

interface IovationClientRequest { 
     String getEmail(); 
     String getIpAddress(); 
} 




// 6
interface AnonymousUserAuthenticator {
    Token authenticate(String username, String password) throws WrongAuthenticationCredentialsProvided;
}

// 7
interface Test { 
    interface TestResult { 
        void print(); 
    } 
    boolean over(); 
    Collection<TestResult> listTestResults(); 
} 

if (test.over()) { 
    for (TestResult tr : test.listTestResults()) { 
        // pretty printing 
        tr.print(); 
    }      
} 

// 8 
// Booleans are queries, but exception to the CQR rule naming. They are not nouns. Let's fix it (guess how).
enum Severity {
  boolean major();
}

class Specification {
  boolean satisfiedBy(Entity entity);
}


// 9
boolean destroyButtonAvailable = 
    widgets
        .stream()
        .filter(Widget::isButton)
        .filter(button -> button.label().equals("Destroy The World"))
        .isPresent();


// 10
interface File { 
     void openAndThrowIfNotFound(); 
}