Series Recap: Coding in the small with Google Collections

Robert Konigsberg, Jerome Mourits and myself have written several snippets that highlight the carefully designed Google Collections Library:

Preconditions

Preconditions.checkNotNull(order.getAddress(), "order address");`</pre>
[Iterables.getOnlyElement](/2007/09/coding-in-small-with-google-collections_9985.html)<pre class="prettyprint">`assertEquals(jesse, Iterables.getOnlyElement(usersOnDuty));`</pre>
[Comparators.max](/2007/09/coding-in-small-with-google-collections_8582.html)<pre class="prettyprint">`return Comparators.max(perKm, minimumDeliveryCharge);`</pre>
[Objects.equal and hashCode](/2007/09/coding-in-small-with-google-collections_8175.html)<pre class="prettyprint">`return Objects.hashCode(address, targetArrivalDate, lineItems);`</pre>
[Lists.immutableList](/2007/09/coding-in-small-with-google-collections_8786.html)<pre class="prettyprint">`this.steps = Lists.immutableList(steps);`</pre>
[Objects.nonNull](/2007/09/coding-in-small-with-google-collections_15.html)<pre class="prettyprint">`his.familyName = Objects.nonNull(familyName);`</pre>
[Iterables.concat](/2007/09/coding-in-small-with-google-collections_18.html)<pre class="prettyprint">`for (LineItem lineItem : Iterables.concat(getPurchasedItems(), getFreeItems())) { 
  ...
}`</pre>
[Constraints.constrainedList](/2007/09/coding-in-small-with-google-collections_8093.html)<pre class="prettyprint">`public void checkElement(LineItem element) { ... }`</pre>
[Multimap](/2007/09/coding-in-small-with-google-collections_19.html)<pre class="prettyprint">`Multimap&lt;Salesperson, Sale&gt; multimap 
    = new ArrayListMultimap&lt;Salesperson,Sale&gt;();`</pre>
[Join](/2007/09/coding-in-small-with-google-collections_20.html)<pre class="prettyprint">`return Join.join(" and ", items);`</pre>
[Maps, Sets and Lists](/2007/09/coding-in-small-with-google-collections_22.html)<pre class="prettyprint">`Set&lt;String&gt; workdays = Sets.newLinkedHashSet(
    "Monday", "Tuesday", "Wednesday", "Thursday", "Friday");`</pre>
[Comparators.fromFunction](/2007/09/coding-in-small-with-google-collections_24.html)<pre class="prettyprint">`return Comparators.fromFunction(new Function&lt;Product,Money&gt;() { ... });`</pre>
[BiMap](/2007/09/coding-in-small-with-google-collections_26.html)<pre class="prettyprint">`return NUMBER_TO_NAME_BIMAP.inverse().get(elementName);`</pre>
[ClassToInstanceMap](/2007/09/coding-in-small-with-google-collections_28.html)<pre class="prettyprint">`T result = optionalValuesByType.getInstance(type);`</pre>
[ImmutableSet](http://publicobject.com/2008/03/coding-in-small-with-google-collections.html)<pre class="prettyprint">`public static final ImmutableSet&lt;Integer&gt; LUCKY_NUMBERS 
      = ImmutableSet.of(4, 8, 15, 16, 23, 42);`</pre>
[Sets.union, intersection and difference](http://publicobject.com/2008/08/coding-in-small-with-google-collections.html)<pre class="prettyprint">`Sets.difference(requestParameters.keySet(), LEGAL_PARAMETERS)

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