34 lines
1.6 KiB
Markdown
34 lines
1.6 KiB
Markdown
# Strategy Design Pattern — Java Example
|
|
|
|
**Pattern:** Behavioral → Strategy
|
|
**Article:** https://ankurm.com/strategy-design-pattern-java/
|
|
|
|
## What this example shows
|
|
|
|
Three sorting algorithms behind one interface, swappable at runtime. `SortStrategy` declares `sort()` and `getName()`. `BubbleSort`, `MergeSort`, and `QuickSort` each implement the full algorithm — not stubs, the real divide-and-conquer and partition logic. `Sorter` is the context: it holds whichever strategy is active and copies the input array before sorting so callers can compare results without mutating their data. `Main` sorts the same array with all three strategies in turn, then simulates choosing a strategy based on input size.
|
|
|
|
## How to run
|
|
|
|
```bash
|
|
javac strategy/*.java -d out/strategy
|
|
java -cp out/strategy strategy.Main
|
|
```
|
|
|
|
Requires Java 25.
|
|
|
|
## Post Section ↔ File Mapping
|
|
|
|
| Post Section | File(s) |
|
|
|---|---|
|
|
| Implementation: Pluggable Sorting — the Strategy interface | `SortStrategy.java` |
|
|
| Implementation: Pluggable Sorting — BubbleSort | `BubbleSort.java` |
|
|
| Implementation: Pluggable Sorting — MergeSort | `MergeSort.java` |
|
|
| Implementation: Pluggable Sorting — QuickSort | `QuickSort.java` |
|
|
| Implementation: Pluggable Sorting — the Context (Sorter) | `Sorter.java` |
|
|
| Implementation: Pluggable Sorting — wiring it together | `Main.java` |
|
|
|
|
Note: the "Strategy in Java 8+: Lambdas as Strategies" snippet (`Comparator`/lambda example) is illustrative only — it is not part of this repository's runnable example.
|
|
|
|
Article: https://ankurm.com/strategy-design-pattern-java/
|
|
All patterns: https://ankurm.com/design-patterns-java/
|