💡 IntelliJ IDEA — Code Snippets (Live Templates & File Templates)¶

🧭 Introduction¶

IntelliJ IDEA supports two powerful snippet systems:

1. Live Templates — dynamic, context-aware snippets you trigger manually inside existing files (e.g., typing yfm → Tab). They use IntelliJ macros like date(), className(), and clipboard() to inject live data.

2. File Templates — static, prefilled structures used when creating new files. They use Velocity-style variables like ${NAME}, ${DATE}, and ${YEAR}-${MONTH}-${DAY}.

Together, they automate everything from boilerplate code to note headers and logging patterns — turning IntelliJ into a serious productivity engine.

🧩 PART 1 — Live Templates¶

⚙️ What Live Templates Are¶

Live Templates let you expand small abbreviations into complete code or text blocks. They’re ideal for repeating structures (YAML headers, annotations, logging, test stubs, etc.) and can include dynamic macros that automatically fill in data such as the date, file name, or user.

Path: Settings → Editor → Live Templates

🧱 Example — Markdown Front Matter with Auto Date¶

Abbreviation: yfm

Template text:

---
title: $TITLE$
date: $DATE$
tags: 

summary: $SUMMARY$
aliases:

---
$END$

Variable setup (Edit Variables…):

Now type yfm → press Tab → IntelliJ expands to:

---
title: 
date: 2025-10-17
tags: 

summary: 
aliases:

---

⚡ Insert or Trigger a Live Template¶

🧰 Commonly Used IntelliJ Macros¶

💡 Power Tips¶

• Prefix abbreviations by category (md_, j_, r_, etc.) to keep lists organized.
• $END$ marks where the cursor lands after expansion.
• $SELECTION$ allows templates that wrap selected text.

• Combine macros:

• capitalize(fileNameWithoutExtension()) → MyFile

• camelCase(clipboard()) → convert copied text to variable name
• uuid().substring(0,8) → short random ID

🏗️ PART 2 — File Templates¶

⚙️ What File Templates Are¶

File Templates define prefilled content for new files. When you create a new file (e.g., “New → MD Note”), IntelliJ uses these templates to populate default text.

They use a simpler syntax — Velocity variables — which look like ${VARIABLE}. These are resolved at creation time, not live while editing.

Path: Settings → Editor → File and Code Templates

🧱 Example — Markdown Note Template¶

Name: MD Note Extension: md

Template text:

---
title: ${NAME}
date: ${YEAR}-${MONTH}-${DAY}
tags: 
summary: 
aliases:
---

Result when creating a new file:

---
title: my-new-note
date: 2025-10-17
tags: 
summary: 
aliases:
---

📘 Common File Template Variables¶

Velocity Tip: You can use expressions like:

${YEAR}-${MONTH}-${DAY}_${TIME}

to generate unique timestamps for file names.

💡 Power Tips¶

• Use File Templates for your recurring file types: configuration files, test classes, documentation stubs.
• Use ${DATE} for locale-aware date or ${YEAR}-${MONTH}-${DAY} for ISO-style.
• Add includes for shared blocks (Settings → File and Code Templates → Includes tab).
• Works great combined with Live Templates — start from a File Template, enhance later with dynamic snippets.

🧭 Quick Reference¶

🧠 Summary¶

Live Templates — dynamic, context-aware snippets for existing files. Use IntelliJ macros such as date(), className(), clipboard(), uuid(), and user() to auto-fill information.

File Templates — static, prefilled structures for new files. Use Velocity-style variables like ${NAME}, ${DATE}, ${YEAR}-${MONTH}-${DAY} to scaffold default content.

Both systems complement each other:

• Live Templates automate repetitive typing.
• File Templates provide consistent starting points. Together, they’re the backbone of a fast, error-free workflow inside IntelliJ IDEA.