[FEATURE] systeminfo

[nihaltp]

Fixes #82

Summary by CodeRabbit

• New Features
  • Introduced the systeminfo command that provides comprehensive system and JVM information including hostname, operating system details, user information, Java vendor and version, available processor count, boot time, user locale, home directory, and detailed memory statistics.

[github-actions]

🚀 Hi @nihaltp!

Thank you for contributing to MyCMD. A maintainer will review your PR shortly. 🎉

[coderabbitai]

Walkthrough

This pull request introduces a new systeminfo command that displays comprehensive system and JVM information, including hostname, OS details, Java vendor, processor count, boot time, locale, home directory, and memory statistics. The command is registered in the command dispatcher and marked as completed in the project checklist.

Changes

Cohort / File(s)	Change Summary
Checklist Update CheckList.md	Mark "System Information & Management" systeminfo item as completed
Command Registration src/main/java/com/mycmd/App.java	Register SysteminfoCommand in registerCommands() method
New Command Implementation src/main/java/com/mycmd/commands/SysteminfoCommand.java	Introduce new SysteminfoCommand class implementing Command interface with execute(), description(), and usage() methods to collect and display system information (hostname, OS, Java vendor, processors, memory stats, boot time, locale, home directory) with error handling for hostname resolution

Sequence Diagram(s)

sequenceDiagram
    participant User
    participant App
    participant SysteminfoCommand
    participant System as System/JVM
    participant Output

    User->>App: Execute systeminfo command
    App->>SysteminfoCommand: Create and execute
    SysteminfoCommand->>System: Query hostname, OS, Java properties
    SysteminfoCommand->>System: Query memory and processor info
    SysteminfoCommand->>System: Query boot time and locale
    System-->>SysteminfoCommand: Return system data
    SysteminfoCommand->>Output: Format and print results
    Output-->>User: Display system information

Loading

Estimated code review effort

🎯 2 (Simple) | ⏱️ ~8 minutes

• SysteminfoCommand.java: Review the system property collection logic, hostname fallback mechanism (environment variable handling), and memory formatting (particularly "No Limit" handling for max heap)
• App.java: Verify command registration integrates correctly with existing command map

Poem

🐰 A new command hops into view,
Systeminfo, revealing what's true—
Memory, processors, Java's bright name,
System secrets, now part of the game! ✨

Pre-merge checks and finishing touches

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 0.00% which is insufficient. The required threshold is 80.00%.	You can run @coderabbitai generate docstrings to improve docstring coverage.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title Check	✅ Passed	The PR title "[FEATURE] systeminfo" directly and accurately describes the primary objective of the changeset. The title clearly communicates that this pull request adds a new systeminfo feature, which aligns with the actual implementation visible in the changes: a new SysteminfoCommand class, its registration in App.java, and documentation of task completion. The title is concise, specific, and avoids vague terminology.
Linked Issues Check	✅ Passed	The linked issue #82 requests the addition of a systeminfo command. The pull request fully addresses this requirement by implementing the SysteminfoCommand class with comprehensive system information collection (hostname, OS details, Java vendor, processors, memory statistics, etc.), registering the command in App.java via the registerCommands method, and updating the checklist to mark the feature as completed. The implementation provides a functional systeminfo command that can be invoked through the application's command framework.
Out of Scope Changes Check	✅ Passed	All changes in the pull request are directly related to implementing the systeminfo command feature requested in issue #82. The SysteminfoCommand class introduces the new command functionality, App.java registers it in the command registry, and CheckList.md documents the completion of this task. No unrelated code modifications, refactorings, or changes to unrelated features are present in the changeset.

✨ Finishing touches

• 📝 Generate docstrings

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Post copyable unit tests in a comment

---

📜 Recent review details

Configuration used: CodeRabbit UI

Review profile: CHILL

Plan: Pro

📥 Commits

Reviewing files that changed from the base of the PR and between 16c762d and e9e295e.

📒 Files selected for processing (3)

• CheckList.md (1 hunks)
• src/main/java/com/mycmd/App.java (1 hunks)
• src/main/java/com/mycmd/commands/SysteminfoCommand.java (1 hunks)

🧰 Additional context used

🧬 Code graph analysis (1)

src/main/java/com/mycmd/commands/SysteminfoCommand.java (1)

src/main/java/com/mycmd/ShellContext.java (1)

• ShellContext (7-151)

🔇 Additional comments (7)

CheckList.md (1)

10-10: LGTM!

The checklist update accurately reflects the completion of the systeminfo command feature.

src/main/java/com/mycmd/App.java (1)

109-110: LGTM!

The command registration follows the established pattern and correctly integrates the new SysteminfoCommand into the command dispatcher.

src/main/java/com/mycmd/commands/SysteminfoCommand.java (5)

14-22: LGTM!

The class properly implements the Command interface and initializes the necessary components for collecting system information. The per-call instantiation of SimpleDateFormat ensures thread-safe usage.

---

23-30: Excellent fallback strategy for hostname resolution.

The implementation provides a robust fallback chain that handles failures gracefully:

1. Attempts InetAddress resolution
2. Falls back to COMPUTERNAME (Windows)
3. Falls back to HOSTNAME (Unix/Linux)
4. Provides "Unknown" as final fallback

This cross-platform approach ensures the command works reliably across different environments.

---

32-37: LGTM!

The memory and uptime calculations use standard JVM management APIs correctly. The boot time derivation and memory metric calculations are accurate.

---

39-62: LGTM!

The output formatting is clear and well-organized. Key strengths:

• Properly converts memory values to MB using 1024*1024
• Correctly handles the edge case where maxMemory equals Long.MAX_VALUE by displaying "No Limit"
• Uses NumberFormat for locale-appropriate number formatting
• System properties used are standard and reliably available

---

65-73: LGTM!

The description and usage methods properly implement the Command interface contract with appropriate, concise documentation.

---

_{Comment @coderabbitai help to get the list of available commands and usage tips.}