PowerPoint Presentation - From C++ to Java

Template for coding findPhone

abstract class DeptDirectory {

abstract String findPhone(String key);

class Empty extends DeptDirectory {

String findPhone(String key) { É }

public String toString() { return "Empty()"; }

}

class Cons extends DeptDirectory {

Entry first;

DeptDirectory rest;

Cons(Entry f, DeptDirectory r) {

this.first = f;

this.rest = r;

}

Entry getFirst() { return this.first; }

DeptDirectory getRest() { return this.rest; }

String findPhone(String key) {

É rest.findPhone(key) É

}

public String toString() { return "NonEmpty(" + first + ", " + rest + ")"; }

}

Fill in this method body