java-refactor

Name: java-refactor
Author: ducpm2303

17stars0forks

How to install java-refactor?

ducpm2303/claude-java-plugins/java-refactor

$npx -y skills add ducpm2303/claude-java-plugins --skill java-refactor

Installs into the current project.

Summary

Suggests and applies version-gated Java refactorings. Use when user asks to "refactor this", "clean up this code", "modernize this Java", "simplify this", "extract method", "improve this class", or "make this more idiomatic".

Files · 1

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SKILL.md

1	Refactor the Java code I've selected or provided. Follow these steps:
2
3	## Step 1 — Detect Java version
4	Check `pom.xml` (`<java.version>` or `<maven.compiler.source>`) or `build.gradle` (`sourceCompatibility`). If not found, ask: "What Java version are you targeting? (8, 11, 17, 21, or other)"
5
6	## Step 2 — Apply safe refactorings (all Java versions)
7	These refactorings are safe regardless of Java version:
8	- Extract method: if a method is longer than 20 lines or has a distinct sub-step, extract it with a descriptive name
9	- Rename for clarity: rename variables, methods, or classes with unclear names
10	- Remove duplication: identify repeated logic blocks and extract to a shared method
11	- Replace magic literals: replace inline numbers/strings with named `static final` constants
12	- Simplify conditionals: replace nested if/else chains with early returns or ternary where clearer
13	- Remove dead code: delete unreachable branches, unused variables, unused imports
14
15	## Step 3 — Apply version-gated refactorings (only if target version supports it)
16	State the minimum Java version required for each suggestion:
17	- Java 8+ — Replace anonymous classes with lambdas: e.g., `new Comparator<String>() { ... }` → `(a, b) -> a.compareTo(b)`
18	- Java 8+ — Replace imperative loops with streams: e.g., for-each + list.add → `list.stream().filter(...).collect(Collectors.toList())`
19	- Java 8+ — Use Optional instead of null returns: e.g., `return null` → `return Optional.empty()`
20	- Java 9+ — Use List.of / Map.of: e.g., `new ArrayList<>(Arrays.asList(...))` → `List.of(...)`
21	- Java 10+ — Use var for local variables: where the type is obvious from the right-hand side
22	- Java 16+ — Replace data classes with records: e.g., a class with only final fields, a constructor, and getters → `record`
23	- Java 17+ — Replace instanceof + cast chains with pattern matching: e.g., `if (obj instanceof String) { String s = (String) obj; }` → `if (obj instanceof String s)`
24
25	## Output format
26	For each refactoring:
27	1. What: one sentence describing the change
28	2. Why: one sentence explaining the benefit
29	3. Before: the original code snippet
30	4. After: the refactored code snippet
31	5. Java version required: (e.g., "Java 8+" or "All versions")
32
33	Then offer: "Want me to apply these changes to the file?"
34
35	## Next Steps
36	After completing refactoring:
37	- If tests don't exist for the refactored code → suggest running `/java-test` to generate tests
38	- If the refactoring changed public API signatures → suggest running `/java-docs` to update Javadoc
39	- Remind the user to run their build: `mvn compile -q` or `./gradlew build -q`

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java-refactor

17stars0forks

View on GitHub

How to install java-refactor?

ducpm2303/claude-java-plugins/java-refactor

$npx -y skills add ducpm2303/claude-java-plugins --skill java-refactor

Installs into the current project.

Summary

Files · 1

View on GitHub

SKILL.md

1	Refactor the Java code I've selected or provided. Follow these steps:
2
3	## Step 1 — Detect Java version
4	Check `pom.xml` (`<java.version>` or `<maven.compiler.source>`) or `build.gradle` (`sourceCompatibility`). If not found, ask: "What Java version are you targeting? (8, 11, 17, 21, or other)"
5
6	## Step 2 — Apply safe refactorings (all Java versions)
7	These refactorings are safe regardless of Java version:
8	- Extract method: if a method is longer than 20 lines or has a distinct sub-step, extract it with a descriptive name
9	- Rename for clarity: rename variables, methods, or classes with unclear names
10	- Remove duplication: identify repeated logic blocks and extract to a shared method
11	- Replace magic literals: replace inline numbers/strings with named `static final` constants
12	- Simplify conditionals: replace nested if/else chains with early returns or ternary where clearer
13	- Remove dead code: delete unreachable branches, unused variables, unused imports
14
15	## Step 3 — Apply version-gated refactorings (only if target version supports it)
16	State the minimum Java version required for each suggestion:
17	- Java 8+ — Replace anonymous classes with lambdas: e.g., `new Comparator<String>() { ... }` → `(a, b) -> a.compareTo(b)`
18	- Java 8+ — Replace imperative loops with streams: e.g., for-each + list.add → `list.stream().filter(...).collect(Collectors.toList())`
19	- Java 8+ — Use Optional instead of null returns: e.g., `return null` → `return Optional.empty()`
20	- Java 9+ — Use List.of / Map.of: e.g., `new ArrayList<>(Arrays.asList(...))` → `List.of(...)`
21	- Java 10+ — Use var for local variables: where the type is obvious from the right-hand side
22	- Java 16+ — Replace data classes with records: e.g., a class with only final fields, a constructor, and getters → `record`
23	- Java 17+ — Replace instanceof + cast chains with pattern matching: e.g., `if (obj instanceof String) { String s = (String) obj; }` → `if (obj instanceof String s)`
24
25	## Output format
26	For each refactoring:
27	1. What: one sentence describing the change
28	2. Why: one sentence explaining the benefit
29	3. Before: the original code snippet
30	4. After: the refactored code snippet
31	5. Java version required: (e.g., "Java 8+" or "All versions")
32
33	Then offer: "Want me to apply these changes to the file?"
34
35	## Next Steps
36	After completing refactoring:
37	- If tests don't exist for the refactored code → suggest running `/java-test` to generate tests
38	- If the refactoring changed public API signatures → suggest running `/java-docs` to update Javadoc
39	- Remind the user to run their build: `mvn compile -q` or `./gradlew build -q`

People who liked this also viewed

6 picks

Type