Crate ristretto_classfile 

Ristretto ClassFile

Implementation of the JVM Class File Format that is used to read, write and verify Java classes.

Supports reading, writing, and verifying class files for any version of Java version up to 25.

Examples

Creating a Simple Class File

use ristretto_classfile::{ClassFile, ConstantPool, Version, JAVA_21};

let mut constant_pool = ConstantPool::default();
let this_class = constant_pool.add_class("Foo")?;
let class_file = ClassFile {
    version: JAVA_21,
    constant_pool,
    this_class,
    ..Default::default()
};
class_file.verify()?;

Reading a Class File from Bytes

use ristretto_classfile::ClassFile;
use std::fs;
use std::io::Cursor;

// Read the bytes of a class file
let bytes = fs::read("path/to/Example.class")?;

// Parse the bytes into a ClassFile
let class_file = ClassFile::from_bytes(&mut Cursor::new(bytes))?;

// Now you can inspect the class
println!("Class name: {}", class_file.class_name()?);
println!("Class version: {}", class_file.version);

Writing a Class File to Bytes

use ristretto_classfile::{ClassFile, ConstantPool, Version, ClassAccessFlags, JAVA_21};
use std::fs;
use std::io::{Cursor, Write};

// Create a new class file
let mut constant_pool = ConstantPool::default();
let this_class = constant_pool.add_class("HelloWorld")?;
let super_class = constant_pool.add_class("java/lang/Object")?;

let class_file = ClassFile {
    version: JAVA_21,
    access_flags: ClassAccessFlags::PUBLIC,
    constant_pool,
    this_class,
    super_class,
    ..Default::default()
};

// Verify the class file is valid
class_file.verify()?;

// Write the class file to a vector of bytes
let mut buffer = Vec::new();
class_file.to_bytes(&mut buffer)?;

// Now you can save these bytes to a file
fs::write("HelloWorld.class", buffer)?;

Re-exports

pub use verifiers::VerifyMode;

Modules

attributes

Attributes Module

mutf8

Functions to convert between Rust strings and Java Modified UTF-8 byte arrays.

verifiers

Verifiers Module

Structs

ClassAccessFlags

Class access flags.

ClassFile

ClassFile represents the content of a Java .class file.

ConstantPool

Constant pool.

Field

Represents a field in a Java class file.

FieldAccessFlags

Field access flags used in Java class files to specify the access permissions and properties of fields.

Method

Method.

MethodAccessFlags

Method access flags used in Java class files to specify the access permissions and properties of methods.

Enums

BaseType

Represents the primitive types in the Java Virtual Machine.

Constant

Constant

Error

Errors that can occur when processing JVM class files.

FieldType

Represents a Java field type descriptor as defined in the JVM specification.

ReferenceKind

Represents the behavior of a dynamic call site in the Java Virtual Machine.

Version

Implementation of Version based on ClassFile format for major/minor versions.

VersionSpecification

Specifies a rule for matching Java versions.

Constants

JAVA_5

Constants representing the Java version 5.0.

JAVA_6

Constants representing the Java version 6.

JAVA_7

Constants representing the Java version 7.

JAVA_8

Constants representing the Java version 8.

JAVA_9

Constants representing the Java version 9.

JAVA_1_0_2

Constants representing the Java version 1.0.2.

JAVA_1_1

Constants representing the Java version 1.1.

JAVA_1_2

Constants representing the Java version 1.2.

JAVA_1_3

Constants representing the Java version 1.3.

JAVA_1_4

Constants representing the Java version 1.4.

JAVA_10

Constants representing the Java version 10.

JAVA_11

Constants representing the Java version 11.

JAVA_12

Constants representing the Java version 12.

JAVA_13

Constants representing the Java version 13.

JAVA_14

Constants representing the Java version 14.

JAVA_15

Constants representing the Java version 15.

JAVA_16

Constants representing the Java version 16.

JAVA_17

Constants representing the Java version 17.

JAVA_18

Constants representing the Java version 18.

JAVA_19

Constants representing the Java version 19.

JAVA_20

Constants representing the Java version 20.

JAVA_21

Constants representing the Java version 21.

JAVA_22

Constants representing the Java version 22.

JAVA_23

Constants representing the Java version 23.

JAVA_24

Constants representing the Java version 24.

JAVA_25

Constants representing the Java version 25.

JAVA_PREVIEW_MINOR_VERSION

Minor version number that indicates a Java preview release.

Type Aliases

Result

A specialized Result type for Ristretto classfile operations.