SETS AND MAPS - Introduction to Java Programming: Comprehensive Version - page 797

CHAPTER

21

S ETS AND M APS

Objectives

To store unordered, nonduplicate elements using a set (§21.2).

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To explore how and when to use HashSet (§21.2.1), LinkedHashSet
(§21.2.2), or TreeSet (§21.2.3) to store a set of elements.

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To compare the performance of sets and lists (§21.3).

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To use sets to develop a program that counts the keywords in a Java
source file (§21.4).

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To tell the differences between Collection and Map and describe
when and how to use HashMap , LinkedHashMap , or TreeMap to
store values associated with keys (§21.5).

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To use maps to develop a program that counts the occurrence of the
words in a text (§21.6).

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To obtain singleton sets, lists, and maps, and unmodifiable sets, lists,
and maps, using the static methods in the Collections class (§21.7).

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