lvm-class 0.4.1

JVM class file parser and writer for the Lagertha VM project
Documentation 
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use crate::attribute::method::{CodeAttribute, MethodAttribute};

impl MethodAttribute {
    pub fn write_to(&self, buf: &mut Vec<u8>) {
        match self {
            MethodAttribute::Code {
                attr_name_idx,
                code_attr,
            } => {
                buf.extend_from_slice(&attr_name_idx.to_be_bytes());
                // TODO: avoid having a buffer, I can know the size before without it.
                let mut body = Vec::new();
                code_attr.write_to(&mut body);
                buf.extend_from_slice(&(body.len() as u32).to_be_bytes());
                buf.extend_from_slice(&body);
            }
            e => unimplemented!("{e:?} attribute writing not implemented yet"),
        }
    }
}

impl CodeAttribute {
    pub fn write_to(&self, buf: &mut Vec<u8>) {
        buf.extend_from_slice(&self.max_stack.to_be_bytes());
        buf.extend_from_slice(&self.max_locals.to_be_bytes());
        buf.extend_from_slice(&(self.code.len() as u32).to_be_bytes());
        buf.extend_from_slice(&self.code);
        buf.extend_from_slice(&(self.exception_table.len() as u16).to_be_bytes());
        for entry in &self.exception_table {
            buf.extend_from_slice(&entry.start_pc.to_be_bytes());
            buf.extend_from_slice(&entry.end_pc.to_be_bytes());
            buf.extend_from_slice(&entry.handler_pc.to_be_bytes());
            buf.extend_from_slice(&entry.catch_type.to_be_bytes());
        }
        buf.extend_from_slice(&(self.attributes.len() as u16).to_be_bytes());
        if !self.attributes.is_empty() {
            todo!("Code attribute with attributes not supported yet");
        }
    }
}