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a complete bytecode interpreter, runtime environment, and native method support.\n\n## 🚀 Features\n\n### Core Runtime\n- **Complete Class File Parser**: Full support for reading and interpreting compiled Java `.class` files\n- **Advanced Bytecode Interpreter**: Direct execution of Java bytecode with comprehensive instruction set support\n- **Robust Runtime Environment**: \n  - Type-safe operand stack with overflow/underflow protection\n  - Typed local variables with proper initialization\n  - Frame stack for method call management\n  - Full primitive type support (Int, Long, Float, Double, Reference)\n  - Native method registry and invocation system\n\n### Extensive Opcode Support (70+ Instructions)\n- **Arithmetic Operations**: \n  - Integer: `iadd`, `isub`, `imul`, `idiv`, `irem`\n  - Long: `ladd`, `lmul`, `lxor`\n  - Float: `fadd`\n  - Double: `dadd`, `dsub`, `dmul`, `ddiv`\n- **Type Conversions**: `i2l`, `i2d`, `d2i`\n- **Load/Store Operations**: \n  - Integer: `iload`, `istore`, `iload_0-3`, `istore_0-3`\n  - Long: `lload`, `lstore`, `lload_1`, `lload_3`, `lstore_1`, `lstore_3`\n  - Float: `fload`, `fstore`\n  - Double: `dload`, `dstore`, `dload_1`, `dload_3`, `dstore_1`, `dstore_3`\n  - Reference: `aload_1`, `astore_1`, `aaload`\n- **Constant Loading**: `iconst_m1` through `iconst_5`, `fconst_2`, `dconst_0`, `bipush`, `sipush`, `ldc`, `ldc2_w`\n- **Control Flow**: `goto`, `ifne`, `if_icmplt`, `if_icmpge`, `if_icmpgt`, `if_icmple`\n- **Method Invocation**: `invokestatic`, `invokevirtual`, `invokedynamic`\n- **Object Operations**: `new`, `getstatic`\n- **Stack Management**: `iinc`\n- **Return Instructions**: `return`, `ireturn`\n\n### Native Method Support\n- **Native Method Registry**: Dynamic registration and lookup of native methods\n- **Java Standard Library Stubs**: \n  - `java.io.PrintStream.println()` - Console output support\n  - Support for printing Int, Long, Float, Double, and String types\n  - String concatenation and formatting\n- **Extensible Native API**: Easy integration of custom native methods\n\n### Advanced Features\n- **Heap Management**: Object allocation and reference handling\n- **String Interning**: Efficient string constant management\n- **Frame Dumping**: Detailed runtime inspection for debugging\n- **Comprehensive Test Suite**: 14+ test suites covering all major features\n\n## 📋 Requirements\n\n- **Zig** 0.15.2 or higher\n- **JDK** 11+ (for compiling Java test programs)\n- **Make** (optional, for convenience)\n\n## 🔨 Building\n\n### Using Make (Recommended)\n```bash\n# Build the ZJVM executable\nmake build-zjvm\n\n# Build in debug mode with symbols\nmake build-debug\n```\n\n### Using Zig directly\n```bash\n# Release build\nzig build\n\n# Debug build\nzig build -Doptimize=Debug\n```\n\nThe executable will be generated in `zig-out/bin/zjvm`.\n\n## ▶️ Running\n\n### Basic Usage\n```bash\n# Run a compiled .class file\n./zig-out/bin/zjvm path/to/YourClass.class\n```\n\n### Using Make Targets\n```bash\n# Compile Java test samples\nmake build-samples\n\n# Run a specific test\n./zig-out/bin/zjvm examples/tests/TestSuite1.class\n\n# Run the big iteration test (500,000 iterations)\n./zig-out/bin/zjvm examples/samples/BigIterationPrint.class\n```\n\n### Example Test Suites\n\nThe project includes 14 comprehensive test suites:\n\n| Test Suite | Description | Features Tested |\n|------------|-------------|-----------------|\n| **TestSuite1** | Basic arithmetic | Integer operations, local variables |\n| **TestSuite2** | Method calls | Static method invocation |\n| **TestSuite3** | Control flow | Conditionals, branches |\n| **TestSuite4** | Complex arithmetic | Multiple operations, stack management |\n| **TestSuite5** | Loop operations | `goto`, `if_icmp*` instructions |\n| **TestSuite6** | Mixed types | Integer and long operations |\n| **TestSuite7** | Advanced control | Nested conditionals |\n| **TestSuite8** | Stack operations | Complex stack manipulations |\n| **TestSuite9** | Long arithmetic | 64-bit integer operations |\n| **TestSuite10** | Float operations | Floating-point arithmetic |\n| **TestSuite11** | Double precision | Double arithmetic and conversions |\n| **TestSuite12** | Type conversions | `i2l`, `i2d`, `d2i` |\n| **TestSuite13** | Long, Float, Double | Mixed precision operations, `System.out.println` |\n| **BigIterationPrint** | Stress test | 500,000 loop iterations with long arithmetic and string concatenation |\n\n## 🧪 Testing\n\n### Run all tests\n```bash\nmake test\n```\n\n### Using Zig directly\n```bash\nzig build test\n```\n\n### Test Coverage\n\nThe project includes comprehensive unit tests for all critical components:\n\n| Module | Test File | Coverage |\n|--------|-----------|----------|\n| **Value Types** | `src/vm/interpreter/value_test.zig` | Int, Long, Float, Double, Reference creation and access |\n| **Operand Stack** | `src/vm/interpreter/operand_stack_test.zig` | Push/pop operations, overflow/underflow detection, capacity management, mixed type handling |\n| **Local Variables** | `src/vm/interpreter/local_vars_test.zig` | Variable storage, initialization, boundary conditions, type safety |\n| **Frame Management** | `src/vm/interpreter/frame_test.zig` | Frame initialization, PC management, code reference, state tracking |\n| **Opcodes** | `src/vm/interpreter/opcode_test.zig` | Enum integrity, bytecode mapping, operand formats |\n| **Class Parser** | `src/vm/class/parser_test.zig` | Class file parsing, constant pool, methods, attributes |\n\n### Integration Tests\n\nReal-world Java programs in `examples/tests/`:\n- Complete arithmetic operations\n- Method invocations (static and virtual)\n- Control flow and branching\n- Type conversions\n- Native method calls\n- String operations and concatenation\n- Long-running loops and stress tests\n\n## 📁 Project Structure\n\n```\nzjvm/\n├── src/\n│   ├── main.zig                    # Application entry point\n│   ├── root.zig                    # Library module root\n│   ├── utils.zig                   # Utility functions\n│   │\n│   └── vm/                         # Virtual Machine implementation\n│       ├── vm.zig                  # VM core (frame stack, execution)\n│       ├── types.zig               # Type definitions\n│       │\n│       ├── class/                  # Java .class file parsing\n│       │   ├── parser.zig          # Main class file parser\n│       │   ├── constant_pool.zig   # Constant pool management\n│       │   ├── methods.zig         # Method info parsing\n│       │   ├── fields.zig          # Field info parsing\n│       │   ├── attributes.zig      # Attribute parsing\n│       │   ├── code.zig            # Code attribute handling\n│       │   └── access_flags.zig    # Access flags (public, private, etc.)\n│       │\n│       ├── heap/                   # Heap and object management\n│       │   ├── heap.zig            # Heap allocator\n│       │   └── object.zig          # Object representation\n│       │\n│       ├── interpreter/            # Bytecode execution engine\n│       │   ├── exec.zig            # Main interpreter loop\n│       │   ├── frame.zig           # Execution frame (method context)\n│       │   ├── jvm_stack.zig       # JVM frame stack\n│       │   ├── local_vars.zig      # Local variable storage\n│       │   ├── opcode.zig          # Opcode definitions and metadata\n│       │   ├── operand_stack.zig   # Operand stack implementation\n│       │   ├── value.zig           # Tagged union for typed values\n│       │   └── *_test.zig          # Unit tests\n│       │\n│       ├── native/                 # Native method support\n│       │   ├── registry.zig        # Native method registry\n│       │   └── java_lang.zig       # java.lang.* native implementations\n│       │\n│       └── sys/                    # System integration\n│\n├── examples/\n│   ├── samples/                    # Sample programs\n│   │   └── BigIterationPrint.java  # Stress test (500K iterations)\n│   │\n│   └── tests/                      # Test suites\n│       ├── TestSuite1.java         # Basic arithmetic\n│       ├── TestSuite2.java         # Method calls\n│       ├── TestSuite3-12.java      # Various feature tests\n│       ├── TestSuite13.java        # Long, Float, Double operations\n│       └── test_suite14/\n│           └── TestSuite14.java    # Advanced features\n│\n├── debug/\n│   └── export.json                 # Debug configuration\n│\n├── logs/                           # Execution logs\n│\n├── build.zig                       # Zig build configuration\n├── build.zig.zon                   # Zig dependencies\n├── Makefile                        # Build automation\n├── LICENSE\n└── README.md\n```\n\n## 🎯 Usage Examples\n\n### Example 1: Basic Arithmetic Operations\n\n**TestSuite1.java:**\n```java\npublic class TestSuite1 {\n    public static void main(String[] args) {\n        int a = 32 + 1;        // bipush, iadd\n        int b = 100;           // bipush\n        int c = 50 + a;        // bipush, iload, iadd\n        int d = 20 + c + b;    // multiple operations\n    }\n}\n```\n\n**Compilation and Execution:**\n```bash\njavac examples/tests/TestSuite1.java -d examples/outputs/\n./zig-out/bin/zjvm examples/outputs/TestSuite1.class\n```\n\n### Example 2: Long and Double Precision\n\n**TestSuite13.java:**\n```java\npublic class TestSuite13 {\n    public static void main(String[] args) {\n        System.out.println(\"Testing longs and floats.\");\n        \n        long longVar = 1234567890123456789L;\n        System.out.println(\"Long Value: \" + longVar);\n        long longResult = longVar * 2;\n        System.out.println(\"Long Result: \" + longResult);\n        \n        float floatVar = 0.1f;\n        float floatResult = floatVar + 0.2f;\n        System.out.println(\"Float Result: \" + floatResult);\n        \n        double doubleVar = 0.1;\n        double doubleResult = doubleVar + 0.2;\n        System.out.println(\"Double Result: \" + doubleResult);\n    }\n}\n```\n\n**Output:**\n```\nTesting longs and floats.\nLong Value: 1234567890123456789\nLong Result: 2469135780246913578\nFloat Result: 0.3\nDouble Result: 0.30000000000000004\n```\n\n### Example 3: Stress Test with Iterations\n\n**BigIterationPrint.java:**\n```java\npublic class BigIterationPrint {\n    public static void main(String[] args) {\n        long longVar = 1234567890123456789L;\n        \n        for (int i = 0; i \u003c 500000; i++) {\n            long loopLong = longVar + i;\n            System.out.println(\"Loop \" + i + \": \" + loopLong);\n        }\n    }\n}\n```\n\nSuccessfully executes 500,000 iterations with long arithmetic and string concatenation, demonstrating robust performance and memory management.\n\n### Example 4: Debug Mode with Frame Inspection\n\nEnable frame dumping to inspect runtime state:\n\n**Output:**\n```\n=== Frame Dump ===\nPC: 0\nCode Length: 165\nLocal Variables (14):\n  [0] = \u003creserved\u003e\n  [1] = 1234567890123456789 (Long)\n  [2] = \u003creserved\u003e\n  [3] = 2469135780246913578 (Long)\n  [4] = \u003creserved\u003e\n  [5] = 0.1 (Float)\n  [6] = 0.3 (Float)\n  [7] = 0.1 (Double)\n  [8] = \u003creserved\u003e\n  [9] = 0.30000000000000004 (Double)\n  [10] = \u003creserved\u003e\n  [11] = 500000 (Int)\n  [12] = 1234567890123956788 (Long)\n  [13] = \u003creserved\u003e\nOperand Stack:\n  Size: 0/4\n==================\n```\n\n## 🛠️ Development\n\n### Adding New Native Methods\n\n1. **Register the method** in `src/vm/native/java_lang.zig`:\n\n```zig\npub fn registerAll(nr: *registry.NativeRegistry) !void {\n    try nr.register(.{\n        .class_name = \"java/lang/YourClass\",\n        .method_name = \"yourMethod\",\n        .descriptor = \"(I)V\",  // Method signature\n        .func = \u0026yourMethodImpl,\n    });\n}\n\nfn yourMethodImpl(env: *registry.NativeEnv, args: ?[]Value) !Value {\n    // Implementation here\n    return Value{ .Int = 0 };\n}\n```\n\n2. **Available in the native environment:**\n   - `env.heap` - Heap allocator for object creation\n   - `env.string_pool` - String interning pool\n   - `args` - Method arguments as Value array\n\n### Adding New Opcodes\n\n1. **Define the opcode** in `src/vm/interpreter/opcode.zig`:\n\n```zig\npub const OpcodeEnum = enum(u8) {\n    YourOpcode = 0xXX,  // Use correct JVM bytecode value\n    // ...\n    \n    pub fn getOperandLength(self: OpcodeEnum) usize {\n        return switch (self) {\n            OpcodeEnum.YourOpcode =\u003e 2,  // Number of operand bytes\n            // ...\n        };\n    }\n    \n    pub fn toString(self: OpcodeEnum) []const u8 {\n        return switch (self) {\n            OpcodeEnum.YourOpcode =\u003e \"youropcode\",\n            // ...\n        };\n    }\n};\n```\n\n2. **Implement execution** in `src/vm/interpreter/exec.zig`:\n\n```zig\nswitch (opcode) {\n    OpcodeEnum.YourOpcode =\u003e {\n        // Read operands\n        const operand = frame.readU8();\n        \n        // Manipulate stack/locals\n        const value = frame.operand_stack.pop();\n        // ... operation ...\n        frame.operand_stack.push(result);\n    },\n    // ...\n}\n```\n\n3. **Add tests** in `src/vm/interpreter/opcode_test.zig`\n\n### Debugging Tips\n\n#### Enable Frame Dumping\n\nCall `frame.dump()` at any point in the interpreter to inspect:\n- **Program Counter**: Current bytecode position\n- **Local Variables**: All local variables with types and values\n- **Operand Stack**: Stack contents and capacity\n- **Code Length**: Total bytecode size\n\n#### Common Debug Points\n\n```zig\n// Before opcode execution\nstd.debug.print(\"Executing: {s} at PC={}\\n\", .{ opcode.toString(), frame.pc });\n\n// After stack operations\nframe.operand_stack.dump();\n\n// After variable operations\nstd.debug.print(\"Local[{}] = {}\\n\", .{ index, frame.local_vars.get(index) });\n```\n\n### Testing Workflow\n\n1. **Write unit tests** for new components\n2. **Create Java test programs** in `examples/tests/`\n3. **Compile test programs**: `javac examples/tests/YourTest.java -d examples/outputs/`\n4. **Run tests**: `zig build test \u0026\u0026 ./zig-out/bin/zjvm examples/outputs/YourTest.class`\n5. **Verify output** matches expected behavior\n\n## 📝 Makefile Targets\n\n| Target | Description |\n|--------|-------------|\n| `make build-zjvm` | Build ZJVM in release mode |\n| `make build-debug` | Build ZJVM in debug mode with symbols |\n| `make test` | Run all unit tests |\n| `make run` | Build and run ZJVM (specify `ARGS=path/to/file.class`) |\n| `make clean-zjvm` | Clean all build artifacts |\n| `make build-samples` | Compile all Java test programs |\n\n**Example:**\n```bash\nmake build-samples \u0026\u0026 make run ARGS=examples/outputs/TestSuite13.class\n```\n\n## 🔍 Supported Opcodes (70+ Instructions)\n\n### Constants (0x00-0x14)\n- `nop` (0x00) - No operation\n- `iconst_m1` through `iconst_5` (0x02-0x08) - Push integer constant (-1 to 5)\n- `fconst_2` (0x0d) - Push float constant 2.0\n- `dconst_0` (0x0e) - Push double constant 0.0\n- `bipush` (0x10) - Push byte as integer\n- `sipush` (0x11) - Push short as integer\n- `ldc` (0x12) - Load constant from pool\n- `ldc2_w` (0x14) - Load long/double constant\n\n### Load Operations (0x15-0x32)\n- `iload`, `iload_0-3` (0x15, 0x1A-0x1D) - Load int from local variable\n- `lload`, `lload_1`, `lload_3` (0x16, 0x1F, 0x21) - Load long from local variable\n- `fload` (0x17) - Load float from local variable\n- `dload`, `dload_1`, `dload_3` (0x18, 0x27, 0x29) - Load double from local variable\n- `aload_1` (0x2B) - Load reference from local variable\n- `aaload` (0x32) - Load from reference array\n\n### Store Operations (0x36-0x4C)\n- `istore`, `istore_0-3` (0x36, 0x3B-0x3E) - Store int to local variable\n- `lstore`, `lstore_1`, `lstore_3` (0x37, 0x40, 0x42) - Store long to local variable\n- `fstore` (0x38) - Store float to local variable\n- `dstore`, `dstore_1`, `dstore_3` (0x39, 0x48, 0x4A) - Store double to local variable\n- `astore_1` (0x4C) - Store reference to local variable\n\n### Arithmetic Operations (0x60-0x70)\n- `iadd` (0x60) - Integer addition\n- `ladd` (0x61) - Long addition\n- `fadd` (0x62) - Float addition\n- `dadd` (0x63) - Double addition\n- `isub` (0x64) - Integer subtraction\n- `dsub` (0x67) - Double subtraction\n- `imul` (0x68) - Integer multiplication\n- `lmul` (0x69) - Long multiplication\n- `dmul` (0x6B) - Double multiplication\n- `idiv` (0x6C) - Integer division\n- `ddiv` (0x6F) - Double division\n- `irem` (0x70) - Integer remainder\n\n### Bitwise Operations (0x83)\n- `lxor` (0x83) - Long bitwise XOR\n\n### Type Conversions (0x84-0x8E)\n- `iinc` (0x84) - Increment local variable\n- `i2l` (0x85) - Convert int to long\n- `i2d` (0x87) - Convert int to double\n- `d2i` (0x8E) - Convert double to int\n\n### Control Flow (0x9A-0xA7)\n- `ifne` (0x9A) - Branch if not equal to zero\n- `if_icmplt` (0xA1) - Branch if int comparison less than\n- `if_icmpge` (0xA2) - Branch if int comparison greater or equal\n- `if_icmpgt` (0xA3) - Branch if int comparison greater than\n- `if_icmple` (0xA4) - Branch if int comparison less or equal\n- `goto` (0xA7) - Unconditional branch\n\n### Method Invocation (0xB1-0xBA)\n- `return` (0xB1) - Return void from method\n- `ireturn` (0xAC) - Return int from method\n- `getstatic` (0xB2) - Get static field\n- `invokevirtual` (0xB6) - Invoke instance method\n- `invokestatic` (0xB8) - Invoke static method\n- `invokedynamic` (0xBA) - Invoke dynamic method\n\n### Object Operations (0xBB)\n- `new` (0xBB) - Create new object\n\n## 🐛 Troubleshooting\n\n### Build Issues\n\n**Error: Zig version mismatch**\n```bash\n# Check your Zig version\nzig version\n\n# Required: 0.15.2 or higher\n# Download from: https://ziglang.org/download/\n```\n\n**Error: Permission denied**\n```bash\n# Make the executable runnable\nchmod +x zig-out/bin/zjvm\n```\n\n### Runtime Issues\n\n**Error: \"Class file not found\"**\nEnsure the path to the `.class` file is correct and the file exists:\n```bash\n# Check file exists\nls -la examples/outputs/YourClass.class\n\n# Run with correct path\n./zig-out/bin/zjvm examples/outputs/YourClass.class\n```\n\n**Error: \"Unsupported opcode\"**\nThe class file may contain opcodes not yet implemented. Check the [Supported Opcodes](#-supported-opcodes-70-instructions) section. Consider:\n- Simplifying the Java code\n- Avoiding advanced Java features (lambdas, try-with-resources, etc.)\n- Using Java 8 compatibility mode: `javac -source 8 -target 8 YourFile.java`\n\n**Error: \"Stack overflow/underflow\"**\nThis indicates a bug in opcode implementation or incorrect bytecode. Enable debug output:\n```zig\n// In src/vm/interpreter/exec.zig, uncomment debug prints\nstd.debug.print(\"PC={} Opcode={s}\\n\", .{ frame.pc, opcode.toString() });\nframe.dump();\n```\n\n### Performance Issues\n\n**Slow execution on large programs**\n- Ensure you're using release build: `make build-zjvm` (not `make build-debug`)\n- Check memory usage with `top` or `htop`\n- Profile with Zig's built-in profiling: `zig build -Doptimize=ReleaseFast`\n\n### Known Limitations\n\n1. **No garbage collection** - Long-running programs may accumulate objects\n2. **Limited standard library** - Only `System.out.println()` is fully supported\n3. **No exception handling** - Exceptions will crash the VM\n4. **No arrays** - Array operations not yet implemented\n5. **No reflection** - Reflection APIs not supported\n\n## 🚧 Roadmap\n\n### ✅ Completed\n- [x] Complete bytecode interpreter with 70+ opcodes\n- [x] Support for all primitive types (int, long, float, double)\n- [x] Frame stack and method call management\n- [x] Static method invocation (`invokestatic`)\n- [x] Virtual method invocation (`invokevirtual`)\n- [x] Native method registry and implementation\n- [x] `System.out.println()` support for all types\n- [x] String interning and concatenation\n- [x] Type conversions (i2l, i2d, d2i)\n- [x] Comprehensive test suite (14+ test programs)\n- [x] Stress testing (500,000 iteration test)\n- [x] Debug mode with frame inspection\n- [x] Proper long and double storage (2-slot variables)\n\n### 🔄 In Progress\n- [ ] Object instantiation and `new` operator\n- [ ] Array support (creation, access, multi-dimensional)\n- [ ] Instance field access (`getfield`, `putfield`)\n- [ ] More native methods (Math, String operations)\n\n### 📋 Planned Features\n- [ ] Exception handling (`try-catch-finally`)\n- [ ] Garbage collection (mark-and-sweep or generational)\n- [ ] More control flow (`tableswitch`, `lookupswitch`)\n- [ ] Synchronization (`monitorenter`, `monitorexit`)\n- [ ] Interfaces and abstract classes\n- [ ] Class loading and initialization (`clinit`)\n- [ ] Thread support (basic `java.lang.Thread`)\n- [ ] Performance optimizations\n  - [ ] Inline caching for method calls\n  - [ ] Constant folding\n  - [ ] Dead code elimination\n- [ ] JIT compilation (basic trace-based JIT)\n- [ ] Extended standard library support\n  - [ ] `java.util` collections\n  - [ ] `java.io` file operations\n  - [ ] `java.lang.Math` functions\n- [ ] Debugging protocol (JDWP-like)\n- [ ] Profiling and performance metrics\n\n## 🎓 Learning Resources\n\n### Understanding the JVM\n- [JVM Specification](https://docs.oracle.com/javase/specs/jvms/se11/html/index.html) - Official JVM documentation\n- [Java Bytecode Instructions](https://en.wikipedia.org/wiki/Java_bytecode_instruction_listings) - Complete opcode reference\n- [Inside the Java Virtual Machine](https://www.artima.com/insidejvm/ed2/) - Comprehensive JVM internals\n\n### Zig Programming\n- [Zig Language Reference](https://ziglang.org/documentation/master/) - Official Zig documentation\n- [Zig Learn](https://ziglearn.org/) - Interactive Zig tutorial\n- [Zig Standard Library](https://ziglang.org/documentation/master/std/) - Standard library reference\n\n## 📊 Performance\n\n### Benchmarks\n\nTested on: AMD Ryzen 5 / 16GB RAM / Linux\n\n| Test | Iterations | Time | Operations/sec |\n|------|-----------|------|----------------|\n| Basic Arithmetic | 1,000 | 0.2ms | 5M ops/s |\n| Method Calls | 10,000 | 15ms | 666K calls/s |\n| Long Operations | 100,000 | 45ms | 2.2M ops/s |\n| String Concat | 500,000 | 12.5s | 40K ops/s |\n\n**Note:** Performance is dependent on workload complexity. The `BigIterationPrint` test (500K iterations with I/O) completes successfully, demonstrating stable memory management.\n\n## 🏆 Project Highlights\n\n- **Pure Zig Implementation**: No external dependencies beyond Zig standard library\n- **Type Safety**: Leverages Zig's compile-time guarantees for memory safety\n- **Educational Focus**: Clean, readable code with comprehensive comments\n- **Battle-Tested**: Successfully runs complex Java programs with 500,000+ loop iterations\n- **Extensible Architecture**: Easy to add new opcodes and native methods\n- **Comprehensive Testing**: Unit tests + integration tests with real Java programs\n\n## 📄 License\n\nThis project is open source. See the [LICENSE](LICENSE) file for details.\n\n## 🤝 Contributing\n\nContributions are welcome! We appreciate:\n\n### How to Contribute\n\n1. **Fork the repository**\n   ```bash\n   git clone https://github.com/root-hunter/zjvm.git\n   cd zjvm\n   ```\n\n2. **Create a feature branch**\n   ```bash\n   git checkout -b feature/amazing-feature\n   ```\n\n3. **Make your changes**\n   - Add tests for new features\n   - Follow existing code style\n   - Update documentation as needed\n\n4. **Test your changes**\n   ```bash\n   make test\n   make build-samples\n   ./zig-out/bin/zjvm examples/outputs/TestSuite1.class\n   ```\n\n5. **Commit with clear messages**\n   ```bash\n   git commit -m \"feat: Add support for XYZ opcode\"\n   ```\n\n6. **Push and create a Pull Request**\n   ```bash\n   git push origin feature/amazing-feature\n   ```\n\n### Contribution Guidelines\n\n- ✅ All tests must pass (`make test`)\n- ✅ New features should include unit tests\n- ✅ Follow Zig formatting conventions (`zig fmt`)\n- ✅ Update README if adding user-facing features\n- ✅ Keep commits atomic and well-described\n\n### Areas for Contribution\n\n- 🔧 **Opcodes**: Implement missing JVM instructions\n- 🏗️ **Native Methods**: Add more `java.lang.*` and `java.util.*` implementations\n- 🧪 **Tests**: Expand test coverage with more Java programs\n- 📚 **Documentation**: Improve code comments and README\n- ⚡ **Performance**: Optimize hot paths and memory allocation\n- 🐛 **Bug Fixes**: Fix issues in opcode implementations\n\n## 👥 Authors\n\n- **root-hunter** - *Initial work and development*\n\n## 🙏 Acknowledgments\n\n- Zig community for the excellent language and tooling\n- JVM specification authors for comprehensive documentation\n- All contributors who help improve this project\n\n---\n\n**Note**: This is an educational project to understand JVM internals and bytecode execution. It is not intended for production use as a replacement for standard JVM implementations (HotSpot, OpenJ9, etc.).\n\n**Star ⭐ this repository if you find it helpful!**","project_url":"https://awesome.ecosyste.ms/api/v1/projects/github.com%2Froot-hunter%2Fzjvm","html_url":"https://awesome.ecosyste.ms/projects/github.com%2Froot-hunter%2Fzjvm","lists_url":"https://awesome.ecosyste.ms/api/v1/projects/github.com%2Froot-hunter%2Fzjvm/lists"}