Spring Call Graph

Visualize method call graphs for Spring Boot Java projects — directly inside VS Code.

Spring Call Graph scans your workspace's Java source files, resolves Spring dependency injection, and renders an interactive, clickable call-flow diagram starting from any method you choose.

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Features

Interactive Call Graph Visualization

Point at any method in your Spring Boot project and instantly see the full execution path — controllers, services, repositories, and beyond.

• Mermaid-based diagram rendered in a dedicated panel
• Clickable nodes — click any node to jump straight to that method in the source file
• Depth slider — adjust traversal depth on the fly without re-running the analysis
• Export the diagram as PNG or JPEG

Two Ways to Trigger Analysis

1. From the Command Palette

Open the Command Palette (Ctrl+Shift+P / Cmd+Shift+P) and run:

Spring: Analyze Method Call Graph

Enter the entry point in the format ClassName#methodName, e.g.:

UserController#createUser

2. Right-click in a Java file

Right-click anywhere inside a method body and choose:

Spring: Show Call Graph from Cursor

The extension automatically detects the enclosing class and method name.

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Spring-Aware Analysis

The extension understands Spring's annotation model and enriches every node with contextual metadata:

Annotation	Recognized as
@RestController, @Controller	Controller layer
@Service, @Transactional	Service layer
@Repository	Repository / DAO layer
@Component, @Configuration	Generic component
@GetMapping, @PostMapping, @PutMapping, @DeleteMapping, @PatchMapping	REST endpoint (method + path shown on node)
@Transactional	Transactional boundary marker
@Async	Async execution marker
@Cacheable	Cache marker
@Autowired, @Inject, @Resource	Dependency injection edge

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Configurable Options

Open Settings (Ctrl+,) and search for Spring Call Graph:

Setting	Default	Description
springCallGraph.maxDepth	5	Maximum traversal depth (1–20)
springCallGraph.excludePackages	java., org.springframework., …	Package prefixes excluded from the graph
springCallGraph.collapseLibraryCalls	true	Collapse external library calls into a single node
springCallGraph.includeObjectCreations	true	Include new ClassName() as graph edges

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Getting Started

1. Open a Spring Boot Java project in VS Code.
2. Open any Java controller or service file.
3. Right-click inside a method → Spring: Show Call Graph from Cursor.
4. The call graph panel opens on the side.
5. Use the depth slider to expand or collapse the graph.
6. Click any node to navigate to that method.

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Requirements

• VS Code 1.85.0 or newer
• A workspace containing .java source files (no compilation required — analysis is purely source-based)

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Extension Settings

{
  // Maximum call graph traversal depth
  "springCallGraph.maxDepth": 5,

  // Packages to exclude from the graph
  "springCallGraph.excludePackages": [
    "java.",
    "javax.",
    "org.springframework.",
    "org.slf4j.",
    "com.fasterxml.",
    "org.apache.",
    "io.micrometer."
  ],

  // Collapse calls into external library methods
  "springCallGraph.collapseLibraryCalls": true,

  // Include object creation (new Foo()) as edges
  "springCallGraph.includeObjectCreations": true
}

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Known Limitations

• Dynamic dispatch / AOP proxies: Runtime proxy behavior (e.g. @Transactional wrapping) is not simulated. The annotation is shown as metadata on the node instead.
• Multiple interface implementations: When a field's type is an interface with multiple implementations, the extension picks the best candidate based on @Primary or @Qualifier annotations. If ambiguity remains, it is flagged on the node.
• No bytecode analysis: Analysis is purely source-based (AST). Methods from pre-compiled dependencies will not be traversed.
• Lambda / method-reference edges: Complex lambda call chains may not be fully resolved.

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Release Notes

0.1.0 — Initial Release

• Source-level Java AST parsing
• Spring annotation recognition (controllers, services, repositories, components)
• REST endpoint detection from mapping annotations
• Interactive Mermaid call graph panel
• Clickable node → navigate to source
• Adjustable traversal depth slider
• Export diagram as PNG / JPEG
• Configurable package exclusions and traversal limits

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Contributing

Issues and pull requests are welcome. Please open a GitHub issue to discuss significant changes before submitting a PR.

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License

MIT