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Groovy / Collections

Collect mapping

Learn Collect mapping in Groovy through a focused explanation, a dedicated topic-specific example, an engineering boundary, and a mastery check.

12 min read • Intermediate

Collect mapping is a focused Groovy lesson inside Collections. The example uses the construct named in the lesson directly rather than reusing a generic placeholder.

Trace the example from its inputs through Collect mapping and identify the behavior that would change if that construct were removed or replaced. Pay attention to the language-specific rules shown by the syntax, because neighboring lessons intentionally exercise different mechanisms.

Topic-specific example

groovy-0032-8413e106fe.groovy
groovy Try It Live 
def prices = [12, 5, 9]
def taxed = prices.collect { it * 1.1 }
println taxed
assert [1,2,3].collect { it * 2 } == [2,4,6]
Edge case / engineering note

For Collect mapping, test one realistic boundary: empty data, invalid input, unavailable resources, lifetime/cleanup, type constraints, or concurrency timing where applicable. A successful happy path is not enough to prove the construct is used correctly.

Content source & attribution
Original Syntaxis Content · Original Syntaxis Content

Lesson quizzes

Collect mapping Mastery Check →
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