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    <p>Let's improve <a href="https://stackoverflow.com/questions/2952732/samples-of-scala-and-java-code-where-scala-code-looks-simpler-has-less-lines/2952776#2952776">stacker's example</a> and use Scala's <a href="http://docs.scala-lang.org/tutorials/tour/case-classes.html" rel="nofollow noreferrer">case classes</a>:</p> <pre><code>case class Person(firstName: String, lastName: String) </code></pre> <p>The above Scala class contains all features of the below Java class, <em>and some more</em> - for example it supports <a href="http://docs.scala-lang.org/tutorials/tour/pattern-matching.html" rel="nofollow noreferrer">pattern matching</a> (which Java doesn't have). Scala 2.8 adds named and default arguments, which are used to generate a <a href="http://www.scala-lang.org/node/2075" rel="nofollow noreferrer">copy method</a> for case classes, which gives the same ability as the with* methods of the following Java class.</p> <pre><code>public class Person implements Serializable { private final String firstName; private final String lastName; public Person(String firstName, String lastName) { this.firstName = firstName; this.lastName = lastName; } public String getFirstName() { return firstName; } public String getLastName() { return lastName; } public Person withFirstName(String firstName) { return new Person(firstName, lastName); } public Person withLastName(String lastName) { return new Person(firstName, lastName); } public boolean equals(Object o) { if (this == o) { return true; } if (o == null || getClass() != o.getClass()) { return false; } Person person = (Person) o; if (firstName != null ? !firstName.equals(person.firstName) : person.firstName != null) { return false; } if (lastName != null ? !lastName.equals(person.lastName) : person.lastName != null) { return false; } return true; } public int hashCode() { int result = firstName != null ? firstName.hashCode() : 0; result = 31 * result + (lastName != null ? lastName.hashCode() : 0); return result; } public String toString() { return "Person(" + firstName + "," + lastName + ")"; } } </code></pre> <p>Then, in usage we have (of course):</p> <pre><code>Person mr = new Person("Bob", "Dobbelina"); Person miss = new Person("Roberta", "MacSweeney"); Person mrs = miss.withLastName(mr.getLastName()); </code></pre> <p>Against</p> <pre><code>val mr = Person("Bob", "Dobbelina") val miss = Person("Roberta", "MacSweeney") val mrs = miss copy (lastName = mr.lastName) </code></pre>
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    1. POSamples of Scala and Java code where Scala code looks simpler/has fewer lines?
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    1. USEsko Luontola
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    1. COYou have to be careful though - case classes inherit from `Product` and hence primitives will be boxed (in scala 2.7) or probably-boxed (2.8 using specialization)
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      1. USoxbow_lakes
    2. COIn 2.7.x and 2.8.0 the only boxing is in `productElements` and `unapply`, not in the constructor, field, or accessor: http://gist.github.com/424375
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    3. COEncourages all sorts of getter/setter badness. Setters should only be added with extreme reluctance, getters should be only added if necessary. Good example of how adding "Simplicity" leads to bad habits.
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      1. USBill K
 

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