Java class files parser for Rust

Introduction

This crate reads and parses Java class files, following the Java Virtual Machine Specification (JVMS), Chapter §4. While there are other crates with similar functionality, the jclassfile crate stands out for its extensive testing within the rusty-jvm project. It has been used to parse thousands of OpenJDK standard library classes and is also exercised through numerous integration tests within the project.

Implementation Status

The following sections of the Java Virtual Machine Specification (JVMS, Java SE 23 Edition) are implemented:

• The ClassFile Structure (§4.1)

• The Constant Pool (§4.4)

  • The CONSTANT_Class_info Structure (§4.4.1)
  • The CONSTANT_Fieldref_info, CONSTANT_Methodref_info, and CONSTANT_InterfaceMethodref_info Structures (§4.4.2)
  • The CONSTANT_String_info Structure (§4.4.3)
  • The CONSTANT_Integer_info and CONSTANT_Float_info Structures (§4.4.4)
  • The CONSTANT_Long_info and CONSTANT_Double_info Structures (§4.4.5)
  • The CONSTANT_NameAndType_info Structure (§4.4.6)
  • The CONSTANT_Utf8_info Structure (§4.4.7)
  • The CONSTANT_MethodHandle_info Structure (§4.4.8)
  • The CONSTANT_MethodType_info Structure (§4.4.9)
  • The CONSTANT_Dynamic_info and CONSTANT_InvokeDynamic_info Structures (§4.4.10)
  • The CONSTANT_Module_info Structure (§4.4.11)
  • The CONSTANT_Package_info Structure (§4.4.12)

• Fields (§4.5)

• Methods (§4.6)

• Attributes (§4.7)

  • The ConstantValue Attribute (§4.7.2)
  • The Code Attribute (§4.7.3)
  • The StackMapTable Attribute (§4.7.4)
  • The Exceptions Attribute (§4.7.5)
  • The InnerClasses Attribute (§4.7.6)
  • The EnclosingMethod Attribute (§4.7.7)
  • The Synthetic Attribute (§4.7.8)
  • The Signature Attribute (§4.7.9)
  • The SourceFile Attribute (§4.7.10)
  • The SourceDebugExtension Attribute (§4.7.11)
  • The LineNumberTable Attribute (§4.7.12)
  • The LocalVariableTable Attribute (§4.7.13)
  • The LocalVariableTypeTable Attribute (§4.7.14)
  • The Deprecated Attribute (§4.7.15)
  • The RuntimeVisibleAnnotations Attribute (§4.7.16)
    • The element_value structure (§4.7.16.1)
  • The RuntimeInvisibleAnnotations Attribute (§4.7.17)
  • The RuntimeVisibleParameterAnnotations Attribute (§4.7.18)
  • The RuntimeInvisibleParameterAnnotations Attribute (§4.7.19)
  • The RuntimeVisibleTypeAnnotations Attribute (§4.7.20)
    • The target_info union (§4.7.20.1)
    • The type_path structure (§4.7.20.2)
  • The RuntimeInvisibleTypeAnnotations Attribute (§4.7.21)
  • The AnnotationDefault Attribute (§4.7.22)
  • The BootstrapMethods Attribute (§4.7.23)
  • The MethodParameters Attribute (§4.7.24)
  • The Module Attribute (§4.7.25)
  • The ModulePackages Attribute (§4.7.26)
  • The ModuleMainClass Attribute (§4.7.27)
  • The NestHost Attribute (§4.7.28)
  • The NestMembers Attribute (§4.7.29)
  • The Record Attribute (§4.7.30)
  • The PermittedSubclasses Attribute (§4.7.31)

• Format Checking (§4.8)

• Constraints on Java Virtual Machine Code (§4.9)

• Verification of class Files (§4.10)

Usage

pub fn main() {
  let file_content = include_bytes!("HelloWorld.class");
  let class_file = jclassfile::class_file::parse(file_content).unwrap();
  println!("{:?}", class_file);
}

Contributing

Contributions are welcome! Feel free to open an issue or submit a pull request.

License

This project is licensed under the MIT License – see the LICENSE file for details.