Given the code format: ``java class DBConfiguration { String user; String password; } ` And the following partial class definition for DBHandler: `java public class DBHandler { DBConfiguration…

Question

class DBConfiguration {
 String user;
 String password;
}

public class DBHandler {
 DBConfiguration configureDB (String uname, String password) {
 // insert code here (line 6)
 }
 public static void main (String[] args) {
 DBHandler r = new DBHandler();
 DBConfiguration dbConf = r.configureDB ("manager", "manager");
 }
}

Options

• ADBConfiguration f;
• Breturn DBConfiguration;
• Creturn new DBConfiguration;
• DRetutn 0;

• A
  13% (7)
• B
  4% (2)
• C
  80% (43)
• D
  4% (2)

Explanation

Option C (return new DBConfiguration;) is the only choice that both creates an instance of DBConfiguration and returns it - which is exactly what the method signature demands, since configureDB declares DBConfiguration as its return type. In Java, a non-void method must have a return statement that hands back a value of the declared type, and new DBConfiguration (intended as new DBConfiguration()) is how you instantiate an object and pass it back to the caller.

Why the distractors fail:

• A (DBConfiguration f;) merely declares a local variable without ever returning anything - the compiler will reject a non-void method with no return statement.
• B (return DBConfiguration;) attempts to return the class name (a type), not an instance of that class - types are not values you can return.
• D (return 0;) returns an int literal, which is incompatible with the DBConfiguration return type - Java is statically typed and will reject the mismatch.

Memory tip: Think of the return type in the method signature as a promise - if you promise to return a DBConfiguration, you must use new to create one and then return it. Whenever return type ≠ void, ask yourself: "Am I returning a fresh instance (new) or an existing variable of that exact type?"

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