Use Java streams where applicable - #4
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jingyucodes wants to merge 5 commits into
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jingyucodes wants to merge 5 commits into
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The "on" and "find" cases in executeCommand() each built a matches list by looping over every task and manually adding the ones that passed a single predicate (occursOn()/matchesKeyword()) — the classic filter-then-collect shape streams exist for, with no early exit, no branching, and no side effects beyond building the result. Replace each loop with tasks.getAll().stream().filter(...) .collect(Collectors.toList()), which states the intent (keep tasks matching this predicate) directly instead of via a manual accumulator loop. Other loops in the codebase (e.g. Ui's numbered task listings, Echo's console read loop) are intentionally left as-is: they either need the running index for output (streams don't index cleanly) or involve stateful, sequential I/O, neither of which streams express more clearly than a plain loop.
save() built its list of save-file lines by looping over tasks and adding task.toFileFormat() for each one — a plain 1-to-1 transformation with no filtering, branching, or side effects, which is exactly what Stream#map exists to express. Replace the loop with tasks.stream().map(Task::toFileFormat) .collect(Collectors.toList()), naming the operation (map) instead of spelling out the accumulator loop that implements it.
load() looped over every line, skipped blanks with a bare continue, parsed the rest, then conditionally added successfully-parsed tasks. That's a filter (skip blank lines) -> map (parse) -> filter (drop failed parses) pipeline expressed as a loop with a mutable accumulator and a continue, which streams state more directly. Rewrite it as Files.readAllLines(filePath).stream() .filter(line -> !line.isBlank()).map(this::parseLine) .filter(Objects::nonNull).collect(Collectors.toList()), returning the stream's result directly instead of building it up in a pre-declared list. parseLine() still prints its own warning for a corrupted line as a side effect inside map(); that's unchanged from before and kept for the same reason (surface the problem without aborting the whole load).
# Conflicts: # src/main/java/echo/storage/Storage.java
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Summary
Echo#executeCommand()'son/findcases: replace manual filter-and-accumulate loops withstream().filter(...).collect(Collectors.toList()).Storage#save(): replace the manual task-to-line loop withstream().map(Task::toFileFormat).collect(Collectors.toList()).Storage#load(): replace the filter/parse/filter loop with a singlefilter -> map -> filterstream pipeline.Streams were applied only where the existing loop was a plain filter/map/collect with no early exit, branching, or meaningful side effects. Left as plain loops (and noted in the first commit's message):
Ui's numbered task listings (need the running index),Echo#run()'s console read loop (stateful I/O with an early break), andDialogBox#flip()'sCollections.reverse()call (already a single clean statement).Test plan
./gradlew compileJava checkstyleMainpassestodo/deadline/event/mark/find/on, then reload and confirm the save file round-trips correctly