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copied!<p>Instead of using null, you could use some version of the "null object" design pattern. For example:</p> <pre><code>public class Family { private final PersonList people; public Family(PersonList people) { this.people = people; } public PersonList getPeople() { if (people == null) { return PersonList.NULL; } return people; } public boolean isNull() { return false; } public static Family NULL = new Family(PersonList.NULL) { @Override public boolean isNull() { return true; } }; } import java.util.ArrayList; public class PersonList extends ArrayList<Person> { @Override public Person get(int index) { Person person = null; try { person = super.get(index); } catch (ArrayIndexOutOfBoundsException e) { return Person.NULL; } if (person == null) { return Person.NULL; } else { return person; } } //... more List methods go here ... public boolean isNull() { return false; } public static PersonList NULL = new PersonList() { @Override public boolean isNull() { return true; } }; } public class Person { private Address address; public Person(Address address) { this.address = address; } public Address getAddress() { if (address == null) { return Address.NULL; } return address; } public boolean isNull() { return false; } public static Person NULL = new Person(Address.NULL) { @Override public boolean isNull() { return true; } }; } etc etc etc </code></pre> <p>Then your if statement can become:</p> <pre><code>if (!family.getPeople().get(0).getAddress().getPostalCode.isNull()) {...} </code></pre> <p>It's suboptimal since:</p> <ul> <li>You're stuck making NULL objects for every class,</li> <li>It's hard to make these objects generic, so you're stuck making a null-object version of each List, Map, etc that you want to use, and</li> <li>There are potentially some funny issues with subclassing and which NULL to use.</li> </ul> <p>But if you really hate your <code>== null</code>s, this is a way out.</p>

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