finally picked it up again, one bytecode at a time

src/class.rs

@@ -10,10 +10,7 @@ pub(crate) struct TypeIndex {
 
 impl TypeIndex {
     pub(crate) fn new(type_name: String, index: usize) -> Self {
-        Self {
-            type_name,
-            index,
-        }
+        Self { type_name, index }
     }
 }
 
@@ -23,14 +20,21 @@ pub struct Class {
     pub initialized: bool,
     pub name: String,
     pub superclass: Option<ClassId>,
-    pub parents: LinkedList<ClassId>,
+    pub all_superclasses: LinkedList<ClassId>, // all superclasses in a flat list
     pub interfaces: Vec<ClassId>,
+    pub all_interfaces: Vec<ClassId>, // all interfaces and their parents in a flat list
     // lookup index and type from the name of the declared class and then field
     pub(crate) object_field_mapping: HashMap<String, HashMap<String, TypeIndex>>,
     pub(crate) static_field_mapping: HashMap<String, HashMap<String, TypeIndex>>,
     // pub(crate) static_field_data: Vec<Value> // moved to classmanager
 }
 
+impl PartialEq for Class {
+    fn eq(&self, other: &Self) -> bool {
+        self.id == other.id
+    }
+}
+
 impl Class {
     /// gets the number of non-static fields on the class
     pub(crate) fn n_object_fields(&self) -> usize {

src/classloader/classdef.rs

@@ -21,7 +21,7 @@ pub(crate) struct ClassDef {
     pub attributes: HashMap<String, AttributeType>,
 }
 
-impl Debug for ClassDef{
+impl Debug for ClassDef {
     fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
         write!(f, "{}", self.cp_class_name(&self.this_class))
     }
@@ -94,6 +94,7 @@ impl ClassDef {
         }
     }
 
+    // gets the class name if the index is a class ref index
     pub fn cp_class_name(&self, index: &u16) -> &String {
         let cr = self.cp_class_ref(index);
         self.cp_utf8(cr)
@@ -318,13 +319,13 @@ impl Field {
     }
 }
 
-pub(crate) struct Method {
+pub struct Method {
     pub(crate) constant_pool: Rc<HashMap<u16, CpEntry>>,
-    access_flags: u16,
+    pub access_flags: u16,
     name_index: u16,
     descriptor_index: u16,
     pub(crate) attributes: HashMap<String, AttributeType>,
-    pub code: Vec<Opcode>,
+    pub(crate) code: Vec<Opcode>,
 }
 
 impl Debug for Method {

src/classloader/io.rs

@@ -1,8 +1,8 @@
 use std::fs::{self};
 
-use anyhow::{anyhow, Error};
 use crate::vm::opcodes::Opcode;
 use crate::vm::opcodes::Opcode::*;
+use anyhow::{anyhow, Error};
 
 #[cfg(target_family = "unix")]
 pub const PATH_SEPARATOR: char = ':';
@@ -17,7 +17,6 @@ pub const PATH_SEPARATOR: char = ';';
 /// * [jar/zip]#[package_path]/[class].class
 /// * [dir]/[package_path]/[class].class
 pub fn find_class(classpath: &Vec<String>, class_name: &str) -> Result<String, Error> {
-    let class_name = &class_name.to_owned().replace(".", "/");
     if class_name.starts_with("java")
         || class_name.starts_with("sun/")
         || class_name.starts_with("com/sun/")
@@ -45,7 +44,6 @@ pub fn find_class(classpath: &Vec<String>, class_name: &str) -> Result<String, E
     Err(anyhow!("Class not found {}", class_name))
 }
 
-
 // methods to read values from big-endian binary data
 
 pub(crate) fn read_u8(data: &[u8], pos: &mut usize) -> u8 {
@@ -73,6 +71,15 @@ pub(crate) fn read_u16(data: &[u8], pos: &mut usize) -> u16 {
     )
 }
 
+pub(crate) fn read_i16(data: &[u8], pos: &mut usize) -> i16 {
+    *pos += 2;
+    i16::from_be_bytes(
+        data[*pos - 2..*pos]
+            .try_into()
+            .expect("slice with incorrect length"),
+    )
+}
+
 pub(crate) fn read_i32(data: &[u8], pos: &mut usize) -> i32 {
     *pos += 4;
     i32::from_be_bytes(
@@ -119,8 +126,9 @@ pub(crate) fn read_f64(data: &[u8], pos: &mut usize) -> f64 {
 }
 
 pub(crate) fn read_tableswitch(data: &[u8], pos: &mut usize) -> Tableswitch {
-    while read_u8(data, pos) == 0 {}
-    *pos -= 1;
+    while *pos % 4 != 0 {
+        *pos += 1;
+    }
     let default = read_i32(data, pos);
     let low = read_i32(data, pos);
     let high = read_i32(data, pos);
@@ -128,19 +136,28 @@ pub(crate) fn read_tableswitch(data: &[u8], pos: &mut usize) -> Tableswitch {
     for _ in low..=high {
         offsets.push(read_i32(data, pos));
     }
-    Tableswitch { default, low, high, offsets }
+    Tableswitch {
+        default,
+        low,
+        high,
+        offsets,
+    }
 }
 
 pub(crate) fn read_lookupswitch(data: &[u8], pos: &mut usize) -> Lookupswitch {
-    while read_u8(data, pos) == 0 {}
-    *pos -= 1;
+    while *pos % 4 != 0 {
+        *pos += 1;
+    }
     let default = read_i32(data, pos);
     let npairs = read_i32(data, pos);
     let mut match_offset_pairs = vec![];
     for _ in 0..npairs {
         match_offset_pairs.push((read_i32(data, pos), read_i32(data, pos)));
     }
-    Lookupswitch { default, match_offset_pairs }
+    Lookupswitch {
+        default,
+        match_offset_pairs,
+    }
 }
 
 pub(crate) fn read_wide_opcode(data: &[u8], pos: &mut usize) -> Opcode {
@@ -161,7 +178,9 @@ pub(crate) fn read_wide_opcode(data: &[u8], pos: &mut usize) -> Opcode {
             57 => WIDE_DSTORE(index),
             58 => WIDE_ASTORE(index),
             169 => WIDE_RET(index),
-            _ => { unreachable!("unknown opcode for WIDE") }
+            _ => {
+                unreachable!("unknown opcode for WIDE")
+            }
         }
     }
 }

src/classloader/mod.rs

@@ -7,15 +7,19 @@ use std::rc::Rc;
 use anyhow::Error;
 use log::debug;
 
-use crate::classloader::io::{find_class, read_bytes, read_f32, read_f64, read_i32, read_i64, read_u16, read_u32, read_u8};
-use crate::classloader::classdef::{AttributeType, ClassDef, CpEntry, Exception, Field, Method, MethodCode};
-use crate::classloader::code_parser::parse_code;
+use crate::classloader::classdef::{
+    AttributeType, ClassDef, CpEntry, Exception, Field, Method, MethodCode,
+};
+use crate::classloader::io::{
+    find_class, read_bytes, read_f32, read_f64, read_i32, read_i64, read_u16, read_u32, read_u8,
+};
+use crate::classloader::opcode_parser::parse_opcodes;
 
 pub mod classdef;
 pub(crate) mod io;
-mod code_parser;
+mod opcode_parser;
 
-pub(crate) fn get_classdef(classpath: &Vec<String>, class_name: &str) -> Result<ClassDef,Error> {
+pub(crate) fn get_classdef(classpath: &Vec<String>, class_name: &str) -> Result<ClassDef, Error> {
     debug!("read class {} ", class_name);
     let resolved_path = find_class(classpath, class_name)?;
     let bytecode = read_bytecode(resolved_path)?;
@@ -64,7 +68,11 @@ fn load_class(bytecode: Vec<u8>) -> Result<ClassDef, Error> {
     let access_flags = read_u16(&bytecode, pos);
     let this_class = read_u16(&bytecode, pos);
     let super_class = read_u16(&bytecode, pos);
-    let super_class = if super_class != 0 { Some(super_class) } else { None };
+    let super_class = if super_class != 0 {
+        Some(super_class)
+    } else {
+        None
+    };
     let interfaces_count = read_u16(&bytecode, pos);
     let mut interfaces = vec![];
     for _ in 0..interfaces_count {
@@ -96,8 +104,6 @@ fn load_class(bytecode: Vec<u8>) -> Result<ClassDef, Error> {
         }
     }
 
-
-
     Ok(ClassDef::new(
         minor_version,
         major_version,
@@ -232,6 +238,7 @@ fn read_method(
 ) -> Method {
     let access_flags = read_u16(bytecode, index);
     let name_index = read_u16(bytecode, index);
+    let name = constant_pool.get(&name_index);
     let descriptor_index = read_u16(bytecode, index);
     let attributes_count = read_u16(bytecode, index);
 
@@ -242,10 +249,9 @@ fn read_method(
         }
     }
 
-    let code =
-    if let Some(AttributeType::Code(code)) = attributes.get("Code") {
-        parse_code(&code.opcodes)
-    } else{
+    let code = if let Some(AttributeType::Code(code)) = attributes.get("Code") {
+        parse_opcodes(&code.opcodes)
+    } else {
         vec![]
     };
 
@@ -255,7 +261,7 @@ fn read_method(
         name_index,
         descriptor_index,
         attributes,
-        code
+        code,
     )
 }
 
@@ -318,12 +324,11 @@ fn read_attribute(
             "InnerClasses" => Some(("".into(), AttributeType::InnerClasses)),       //stub
             "Signature" => Some(("".into(), AttributeType::Signature)),             //stub
             "NestHost" => Some(("".into(), AttributeType::NestHost)),               //stub
-            "EnclosingMethod" => Some(("".into(), AttributeType::EnclosingMethod)),               //stub
-            "PermittedSubclasses" => Some(("".into(), AttributeType::PermittedSubclasses)),               //stub
+            "EnclosingMethod" => Some(("".into(), AttributeType::EnclosingMethod)), //stub
+            "PermittedSubclasses" => Some(("".into(), AttributeType::PermittedSubclasses)), //stub
             //TODO more actual attribute implementations
             _ => None,
         };
     }
     None
 }
-

src/classloader/opcode_parser.rs

@@ -1,39 +1,50 @@
-use std::collections::HashMap;
-
 use log::debug;
+use std::collections::BTreeMap;
 
-use crate::classloader::io::{read_i32, read_lookupswitch, read_tableswitch, read_u16, read_u8, read_wide_opcode};
+use crate::classloader::io::{
+    read_i16, read_i32, read_lookupswitch, read_tableswitch, read_u16, read_u8, read_wide_opcode,
+};
 use crate::vm::opcodes::Opcode::{self, *};
 
-pub(crate) fn parse_code(opcodes: &[u8]) -> Vec<Opcode> {
-    let mut code: HashMap<u16, (u16, Opcode)> = HashMap::new();
+pub(crate) fn parse_opcodes(opcodes: &[u8]) -> Vec<Opcode> {
+    let mut code: BTreeMap<u16, (u16, Opcode)> = BTreeMap::new();
     let mut c = 0;
     let mut opcode_index: u16 = 0;
-    // debug!("len {:?}", opcodes.len());
+    let mut index_before_read: u16;
     while c < opcodes.len() {
+        index_before_read = c as u16;
         let opcode = get_opcode(opcodes, &mut c);
-        code.insert(c as u16, (opcode_index, opcode));
+        code.insert(index_before_read, (opcode_index, opcode));
         opcode_index += 1;
     }
     let code2 = code.clone(); //clone to look up
 
     // for jumps, map index of opcode as u8 to index of opcode as enum
-    code.into_iter().map(|(_, (_, opcode))|
-        match opcode {
-            IFNULL(goto) => {
-                debug!("goto {:?}", goto);
-                debug!("{:?}", code2);
-                IFNULL(code2.get(&goto).unwrap().0)
-            }
-            IFNONNULL(goto) => {
-                debug!("goto {:?}", &goto);
-                debug!("{:?}", code2);
-                IFNONNULL(code2.get(&goto).unwrap().0)
-            }
+    debug!("{:?}", code);
+    code.into_iter()
+        .map(|(_, (_, opcode))| match opcode {
+            IFNULL(goto) => IFNULL(code2.get(&goto).unwrap().0),
+            IFNONNULL(goto) => IFNONNULL(code2.get(&goto).unwrap().0),
+
+            IF_ICMPEQ(goto) => IF_ICMPEQ(code2.get(&goto).unwrap().0),
+            IF_ICMPNE(goto) => IF_ICMPNE(code2.get(&goto).unwrap().0),
+            IF_ICMPGT(goto) => IF_ICMPGT(code2.get(&goto).unwrap().0),
+            IF_ICMPGE(goto) => IF_ICMPGE(code2.get(&goto).unwrap().0),
+            IF_ICMPLT(goto) => IF_ICMPLT(code2.get(&goto).unwrap().0),
+            IF_ICMPLE(goto) => IF_ICMPLE(code2.get(&goto).unwrap().0),
+            IFEQ(goto) => IFEQ(code2.get(&goto).unwrap().0),
+            IFNE(goto) => IFNE(code2.get(&goto).unwrap().0),
+            IFGT(goto) => IFGT(code2.get(&goto).unwrap().0),
+            IFGE(goto) => IFGE(code2.get(&goto).unwrap().0),
+            IFLT(goto) => IFLT(code2.get(&goto).unwrap().0),
+            IFLE(goto) => IFLE(code2.get(&goto).unwrap().0),
+            GOTO(goto) => GOTO(code2.get(&goto).unwrap().0),
+            IF_ACMPEQ(goto) => GOTO(code2.get(&goto).unwrap().0),
+            IF_ACMPNE(goto) => GOTO(code2.get(&goto).unwrap().0),
             //TODO more jump instructions
-            _ => opcode
-        }
-    ).collect()
+            _ => opcode,
+        })
+        .collect()
 }
 
 fn get_opcode(opcodes: &[u8], c: &mut usize) -> Opcode {
@@ -162,6 +173,8 @@ fn get_opcode(opcodes: &[u8], c: &mut usize) -> Opcode {
         121 => LSHL,
         122 => ISHR,
         123 => LSHR,
+        124 => IUSHR,
+        125 => LUSHR,
         126 => IAND,
         127 => LAND,
         128 => IOR,
@@ -189,26 +202,27 @@ fn get_opcode(opcodes: &[u8], c: &mut usize) -> Opcode {
         150 => FCMPG,
         151 => DCMPL,
         152 => DCMPG,
-        153 => IFEQ(read_u16(opcodes, c)),
-        154 => IFNE(read_u16(opcodes, c)),
-        155 => IFLT(read_u16(opcodes, c)),
-        156 => IFGE(read_u16(opcodes, c)),
-        157 => IFGT(read_u16(opcodes, c)),
-        158 => IFLE(read_u16(opcodes, c)),
-        159 => IF_ICMPEQ(read_u16(opcodes, c)),
-        160 => IF_ICMPNE(read_u16(opcodes, c)),
-        161 => IF_ICMPLT(read_u16(opcodes, c)),
-        162 => IF_ICMPGE(read_u16(opcodes, c)),
-        163 => IF_ICMPGT(read_u16(opcodes, c)),
-        164 => IF_ICMPLE(read_u16(opcodes, c)),
-        165 => IF_ACMPEQ(read_u16(opcodes, c)),
-        166 => IF_ACMPNE(read_u16(opcodes, c)),
-        167 => GOTO(read_u16(opcodes, c)),
-        168 => JSR(read_u16(opcodes, c)),
+        153 => IFEQ(offset(opcodes, c)),
+        154 => IFNE(offset(opcodes, c)),
+        155 => IFLT(offset(opcodes, c)),
+        156 => IFGE(offset(opcodes, c)),
+        157 => IFGT(offset(opcodes, c)),
+        158 => IFLE(offset(opcodes, c)),
+        159 => IF_ICMPEQ(offset(opcodes, c)),
+        160 => IF_ICMPNE(offset(opcodes, c)),
+        161 => IF_ICMPLT(offset(opcodes, c)),
+        162 => IF_ICMPGE(offset(opcodes, c)),
+        163 => IF_ICMPGT(offset(opcodes, c)),
+        164 => IF_ICMPLE(offset(opcodes, c)),
+        165 => IF_ACMPEQ(offset(opcodes, c)),
+        166 => IF_ACMPNE(offset(opcodes, c)),
+        167 => GOTO(offset(opcodes, c)),
+        168 => JSR(offset(opcodes, c)),
         169 => RET(read_u8(opcodes, c)),
         170 => TABLESWITCH(read_tableswitch(opcodes, c)),
         171 => LOOKUPSWITCH(read_lookupswitch(opcodes, c)),
         172 => IRETURN,
+        173 => LRETURN,
         174 => FRETURN,
         175 => DRETURN,
         176 => ARETURN,
@@ -242,21 +256,19 @@ fn get_opcode(opcodes: &[u8], c: &mut usize) -> Opcode {
         195 => MONITOREXIT,
         196 => WIDE(Box::new(read_wide_opcode(opcodes, c))),
         197 => MULTIANEWARRAY(read_u16(opcodes, c), read_u8(opcodes, c)),
-        198 => {
-            let j = read_u16(opcodes, c);
-            debug!("ifnull {}",*c as u16 + j - 3);
-            IFNULL(*c as u16 + j - 3)
-        }
-        199 => {
-            let j = read_u16(opcodes, c);
-            debug!("ifnonnull {} ", *c as u16 + j - 3);
-            IFNONNULL(*c as u16 + j - 3)
-        }
+        198 => IFNULL(offset(opcodes, c)),
+        199 => IFNONNULL(offset(opcodes, c)),
         200 => GOTOW(read_i32(opcodes, c)),
         201 => JSR_W(read_i32(opcodes, c)),
 
-
         _ => panic!("{}", opcode_u8),
     };
+    // debug!("{}: {:?}", c, opcode);
     opcode
 }
+
+fn offset(opcodes: &[u8], c: &mut usize) -> u16 {
+    let j = read_i16(opcodes, c);
+    // debug!("JUMP TO {} + {}",c, j);
+    (*c as i16 + j - 3) as u16
+}

src/classmanager.rs

@@ -8,12 +8,13 @@ use once_cell::sync::Lazy;
 use crate::class::{Class, ClassId, TypeIndex};
 use crate::classloader;
 use crate::classloader::classdef::{ClassDef, Method, Modifier};
-use crate::vm::object::{Object, ObjectRef};
 use crate::value::Value;
 use crate::value::Value::*;
+use crate::vm::object::{Object, ObjectRef};
 use crate::vm::runtime::Vm;
 
-static PRIMITIVES: Lazy<Vec<&str>> = Lazy::new(|| vec!["B", "S", "I", "J", "F", "D", "Z", "J", "C"]);
+static PRIMITIVES: Lazy<Vec<&str>> =
+    Lazy::new(|| vec!["B", "S", "I", "J", "F", "D", "Z", "J", "C"]);
 
 //TODO less pubs
 pub struct ClassManager {
@@ -99,11 +100,11 @@ impl ClassManager {
             if !PRIMITIVES.contains(&type_name.as_str()) {
                 type_name = type_name[1..type_name.len()].to_owned();
             }
-            let id = self.get_or_new_id(name);
+            let id = self.get_or_new_id(name.into());
             if !self.class_objects.contains_key(&id) {
                 let cls = self.get_class_by_name("java/lang/Class").unwrap();
                 let mut instance = Object::new(cls);
-                instance.set(cls, "java/lang/Class", "name", Value::Utf8(name.into()));
+                instance.set(cls, "java/lang/Class", "name", Utf8(name.into()));
                 let instance = Ref(ObjectRef::Object(Rc::new(RefCell::new(instance))));
 
                 self.class_objects.insert(id, instance);
@@ -112,8 +113,10 @@ impl ClassManager {
             // in cache?
             let id = self.names.get(&type_name);
             match id {
-                Some(id) => if self.classes.get(id).is_none() {
-                    self.add_class(&type_name);
+                Some(id) => {
+                    if self.classes.get(id).is_none() {
+                        self.add_class(&type_name);
+                    }
                 }
                 None => {
                     self.add_class(&type_name);
@@ -135,6 +138,7 @@ impl ClassManager {
     }
 
     pub fn get_class_by_name(&self, name: &str) -> Option<&Class> {
+        debug!("get class by name {}", name);
         let id = self.names.get(name);
         self.classes.get(id.unwrap())
     }
@@ -166,42 +170,62 @@ impl ClassManager {
         while let Some(c) = current_id {
             parents.push_front(current_id.unwrap());
             current_classdef = self.classdefs.get(&c).unwrap();
-            Self::add_fields_for_this_or_parents(&mut object_field_mapping, &mut static_field_mapping, object_field_map_index, static_field_map_index, current_classdef);
+            Self::add_fields_for_this_or_parents(
+                &mut object_field_mapping,
+                &mut static_field_mapping,
+                object_field_map_index,
+                static_field_map_index,
+                current_classdef,
+            );
 
-            current_id = current_classdef.super_class.as_ref()
+            current_id = current_classdef
+                .super_class
+                .as_ref()
                 .map(|i| current_classdef.cp_class_name(i).to_owned())
                 .map(|n| *self.names.get(&n).unwrap());
         }
 
         //handrolled references to superclass and interfaces
-        let superclass_id = this_classdef.super_class.as_ref()
+        let superclass_id = this_classdef
+            .super_class
+            .as_ref()
             .map(|i| this_classdef.cp_class_name(i).to_owned())
             .map(|n| *self.names.get(&n).unwrap());
 
-        let interface_ids: Vec<ClassId> = this_classdef.interfaces.iter()
+        let interface_ids: Vec<ClassId> = this_classdef
+            .interfaces
+            .iter()
             .map(|i| this_classdef.cp_class_name(i).to_owned())
             .map(|n| *self.names.get(n.as_str()).unwrap())
             .collect();
 
-        // initial values for static fields (before static init)
-        self.static_class_data.insert(this_classid, Self::set_field_data(&static_field_mapping));
+        let mut all_interfaces = Vec::new();
+        self.get_all_interfaces(&interface_ids, &mut all_interfaces);
 
-        self.classes.insert(this_classid, Class {
-            id: this_classid,
-            initialized: false,
-            name: name.into(),
-            superclass: superclass_id,
-            parents,
-            interfaces: interface_ids,
-            object_field_mapping,
-            static_field_mapping,
-        });
+        // initial values for static fields (before static init)
+        self.static_class_data
+            .insert(this_classid, Self::set_field_data(&static_field_mapping));
+
+        self.classes.insert(
+            this_classid,
+            Class {
+                id: this_classid,
+                initialized: false,
+                name: name.into(),
+                superclass: superclass_id,
+                all_superclasses: parents,
+                interfaces: interface_ids,
+                all_interfaces,
+                object_field_mapping,
+                static_field_mapping,
+            },
+        );
 
         // add a new Class instance
         if name != "java/lang/Class" {
             let cls = self.get_class_by_name("java/lang/Class").unwrap();
             let mut instance = Object::new(cls);
-            instance.set(cls, "java/lang/Class", "name", Value::Utf8(name.into()));
+            instance.set(cls, "java/lang/Class", "name", Utf8(name.into()));
             let instance = Ref(ObjectRef::Object(Rc::new(RefCell::new(instance))));
 
             self.class_objects.insert(this_classid, instance);
@@ -209,28 +233,44 @@ impl ClassManager {
 
         // run static init
         if this_classdef.methods.contains_key("<clinit>()V") {
-            Vm { stack: Vec::new()}.run2(self, this_classid,"<clinit>()V");
+            Vm { stack: Vec::new() }.run2(self, this_classid, "<clinit>()V");
         }
 
         this_classid
     }
 
+    fn get_all_interfaces(&self, ids: &[ClassId], output: &mut Vec<ClassId>) {
+        for id in ids {
+            output.push(*id);
+            let interfaces = self.classes.get(id).map(|c| c.interfaces.to_vec());
+            if let Some(intf) = interfaces {
+                self.get_all_interfaces(&intf, output);
+            }
+        }
+    }
+
     /// like described above
-    fn add_fields_for_this_or_parents(object_field_mapping: &mut HashMap<String, HashMap<String, TypeIndex>>,
-                                      static_field_mapping: &mut HashMap<String, HashMap<String, TypeIndex>>,
-                                      object_field_map_index: &mut usize,
-                                      static_field_map_index: &mut usize,
-                                      current_classdef: &ClassDef) {
+    fn add_fields_for_this_or_parents(
+        object_field_mapping: &mut HashMap<String, HashMap<String, TypeIndex>>,
+        static_field_mapping: &mut HashMap<String, HashMap<String, TypeIndex>>,
+        object_field_map_index: &mut usize,
+        static_field_map_index: &mut usize,
+        current_classdef: &ClassDef,
+    ) {
         let mut instance_field_mappings: HashMap<String, TypeIndex> = HashMap::new();
         let mut static_field_mappings: HashMap<String, TypeIndex> = HashMap::new();
         for (field_name, field) in &current_classdef.fields {
             if !field.is(Modifier::Static) {
-                instance_field_mappings.insert(field_name.to_owned(),
-                                               TypeIndex::new(field.type_of().to_owned(), *object_field_map_index));
+                instance_field_mappings.insert(
+                    field_name.to_owned(),
+                    TypeIndex::new(field.type_of().to_owned(), *object_field_map_index),
+                );
                 *object_field_map_index += 1;
             } else {
-                static_field_mappings.insert(field_name.to_owned(),
-                                             TypeIndex::new(field.type_of().to_owned(), *static_field_map_index));
+                static_field_mappings.insert(
+                    field_name.to_owned(),
+                    TypeIndex::new(field.type_of().to_owned(), *static_field_map_index),
+                );
                 *static_field_map_index += 1;
             }
         }
@@ -252,25 +292,28 @@ impl ClassManager {
     }
 
     /// loads the class and returns it's dependencies
-    fn load_class_and_deps(&mut self, name: &str) -> (ClassId, Vec<String>) {
-        debug!("load {}", name);
-        let id = self.get_or_new_id(name);
+    fn load_class_and_deps(&mut self, class_name: &str) -> (ClassId, Vec<String>) {
+        debug!("load {}", class_name);
+        let class_name = class_name.to_owned().replace(".", "/");
+        let id = self.get_or_new_id(class_name.clone());
 
-        let classdef = self.classdefs
-            .entry(id)
-            .or_insert_with(|| classloader::get_classdef(&self.classpath, name).expect("ClassNotFound"));
+        let classdef = self.classdefs.entry(id).or_insert_with(|| {
+            classloader::get_classdef(&self.classpath, class_name.as_str()).expect("ClassNotFound")
+        });
         (id, inspect_dependencies(classdef))
     }
 
-    fn get_or_new_id(&mut self, name: &str) -> ClassId {
-        let id = *self.names.entry(name.to_string()).or_insert_with(|| {
+    fn get_or_new_id(&mut self, name: String) -> ClassId {
+        let id = *self.names.entry(name).or_insert_with(|| {
             self.current_id += 1;
             self.current_id
         });
         id
     }
 
-    pub(crate) fn set_field_data(field_mapping: &HashMap<String, HashMap<String, TypeIndex>>) -> Vec<Value> {
+    pub(crate) fn set_field_data(
+        field_mapping: &HashMap<String, HashMap<String, TypeIndex>>,
+    ) -> Vec<Value> {
         let mut field_data = vec![Null; n_fields(field_mapping)];
 
         for (_, this_class) in field_mapping {
@@ -344,27 +387,100 @@ mod test {
 
         // give class C a fields called value
         let mut c_fields = HashMap::new();
-        c_fields.insert("value1".to_owned(), Field::new(constant_pool.clone(), 0, 9, 5, HashMap::new(), 0));
-        c_fields.insert("value2".to_owned(), Field::new(constant_pool.clone(), 0, 10, 5, HashMap::new(), 0));
+        c_fields.insert(
+            "value1".to_owned(),
+            Field::new(constant_pool.clone(), 0, 9, 5, HashMap::new(), 0),
+        );
+        c_fields.insert(
+            "value2".to_owned(),
+            Field::new(constant_pool.clone(), 0, 10, 5, HashMap::new(), 0),
+        );
 
         // Class needs a public (non-static) field called name
         let mut class_fields = HashMap::new();
-        class_fields.insert("name".to_owned(), Field::new(constant_pool.clone(), 1, 2, 5, HashMap::new(), 0));
+        class_fields.insert(
+            "name".to_owned(),
+            Field::new(constant_pool.clone(), 1, 2, 5, HashMap::new(), 0),
+        );
 
         let mut classdefs = HashMap::new();
-        classdefs.insert(1, ClassDef::new(0, 0, constant_pool.clone(), 0, 0, None, vec![], c_fields, HashMap::new(), HashMap::new()));
+        classdefs.insert(
+            1,
+            ClassDef::new(
+                0,
+                0,
+                constant_pool.clone(),
+                0,
+                0,
+                None,
+                vec![],
+                c_fields,
+                HashMap::new(),
+                HashMap::new(),
+            ),
+        );
 
         // preload java.lang.String
-        classdefs.insert(2, ClassDef::new(0, 0, constant_pool.clone(), 0, 6, None, vec![], HashMap::new(), HashMap::new(), HashMap::new()));
+        classdefs.insert(
+            2,
+            ClassDef::new(
+                0,
+                0,
+                constant_pool.clone(),
+                0,
+                6,
+                None,
+                vec![],
+                HashMap::new(),
+                HashMap::new(),
+                HashMap::new(),
+            ),
+        );
 
         // preload java.lang.Class
-        classdefs.insert(3, ClassDef::new(0, 0, constant_pool, 0, 8, None, vec![], class_fields, HashMap::new(), HashMap::new()));
+        classdefs.insert(
+            3,
+            ClassDef::new(
+                0,
+                0,
+                constant_pool,
+                0,
+                8,
+                None,
+                vec![],
+                class_fields,
+                HashMap::new(),
+                HashMap::new(),
+            ),
+        );
         let mut classes = HashMap::new();
         let mut class_field_mapping = HashMap::new();
         let mut fields_declared_by_java_lang_class = HashMap::new();
-        fields_declared_by_java_lang_class.insert("name".to_owned(), TypeIndex { type_name: "java/lang/String".into(), index: 0 });
-        class_field_mapping.insert("java/lang/Class".to_owned(), fields_declared_by_java_lang_class);
-        classes.insert(3, Class { id: 3, initialized: false, name: "".into(), superclass: None, parents: LinkedList::new(), interfaces: vec![], object_field_mapping: class_field_mapping, static_field_mapping: HashMap::new() });
+        fields_declared_by_java_lang_class.insert(
+            "name".to_owned(),
+            TypeIndex {
+                type_name: "java/lang/String".into(),
+                index: 0,
+            },
+        );
+        class_field_mapping.insert(
+            "java/lang/Class".to_owned(),
+            fields_declared_by_java_lang_class,
+        );
+        classes.insert(
+            3,
+            Class {
+                id: 3,
+                initialized: false,
+                name: "".into(),
+                superclass: None,
+                all_superclasses: LinkedList::new(),
+                interfaces: vec![],
+                all_interfaces: vec![],
+                object_field_mapping: class_field_mapping,
+                static_field_mapping: HashMap::new(),
+            },
+        );
 
         let mut cm = ClassManager {
             static_class_data: HashMap::new(),
@@ -379,7 +495,25 @@ mod test {
         let c_id = cm.add_class("C");
         let loaded_class = cm.classes.get(&c_id).unwrap();
 
-        assert_eq!(0, loaded_class.object_field_mapping.get("C").unwrap().get("value1").unwrap().index);
-        assert_eq!(1, loaded_class.object_field_mapping.get("C").unwrap().get("value2").unwrap().index);
+        assert_eq!(
+            0,
+            loaded_class
+                .object_field_mapping
+                .get("C")
+                .unwrap()
+                .get("value1")
+                .unwrap()
+                .index
+        );
+        assert_eq!(
+            1,
+            loaded_class
+                .object_field_mapping
+                .get("C")
+                .unwrap()
+                .get("value2")
+                .unwrap()
+                .index
+        );
     }
 }

src/lib.rs

@@ -1,5 +1,5 @@
+mod class;
 pub mod classloader;
 pub mod classmanager;
 mod value;
-mod class;
 pub mod vm;

src/main.rs

@@ -1,7 +1,10 @@
 use java_rs::vm::runtime::Vm;
 
 fn main() {
-    let vm = Vm::new();
-    vm.run("/Users/Shautvast/dev/java/tests", "testclasses.Main", "main([Ljava/lang/String;)V");
+    let mut vm = Vm::new();
+    vm.run(
+        "/Users/Shautvast/dev/java.rs/tests",
+        "testclasses/Main",
+        "main([Ljava/lang/String;)V",
+    );
 }
-

src/value.rs

@@ -1,4 +1,5 @@
 use crate::vm::object::ObjectRef;
+use std::ops::{Add, AddAssign};
 
 #[derive(Debug, Clone)]
 pub enum Value {
@@ -12,14 +13,36 @@ pub enum Value {
     F32(f32),
     F64(f64),
     BOOL(bool),
-    CHAR(char),
+    CHAR(i32),
     // objects and arrays
     Ref(ObjectRef),
     // special object
     Utf8(String),
 }
 
+pub enum ComputationalType {
+    C1 = 1,
+    C2 = 2,
+}
+
 impl Value {
+    pub fn category_as_u8(&self) -> u8 {
+        self.category() as u8
+    }
+    pub fn category(&self) -> ComputationalType {
+        match self {
+            Value::Void
+            | Value::Null
+            | Value::I32(_)
+            | Value::F32(_)
+            | Value::BOOL(_)
+            | Value::CHAR(_)
+            | Value::Ref(_)
+            | Value::Utf8(_) => ComputationalType::C1,
+            Value::I64(_) | Value::F64(_) => ComputationalType::C2,
+        }
+    }
+
     // panics if not correct type
     pub fn into_i32(self) -> i32 {
         if let Value::I32(v) = self {
@@ -29,8 +52,42 @@ impl Value {
         }
     }
 
+    pub fn into_i64(self) -> i64 {
+        if let Value::I64(v) = self {
+            v
+        } else {
+            panic!("{:?} is not I64", self);
+        }
+    }
+
+    pub fn into_f32(self) -> f32 {
+        if let Value::F32(v) = self {
+            v
+        } else {
+            panic!("{:?} is not F32", self);
+        }
+    }
+
+    pub fn into_f64(self) -> f64 {
+        if let Value::F64(v) = self {
+            v
+        } else {
+            panic!("{:?} is not F64", self);
+        }
+    }
+
     pub fn into_object(self) -> ObjectRef {
-        if let Value::Ref(v) = self {
+        if let Value::Null = self {
+            ObjectRef::Null
+        } else if let Value::Ref(v) = self {
+            v
+        } else {
+            panic!("{:?}", self);
+        }
+    }
+
+    pub fn into_utf8(self) -> String {
+        if let Value::Utf8(v) = self {
             v
         } else {
             panic!();

src/vm/array.rs

@@ -1,15 +1,15 @@
-use anyhow::{anyhow, Error};
 use crate::vm::object::ObjectRef::*;
+use anyhow::{anyhow, Error};
 
 use crate::value::Value;
 use crate::value::Value::*;
-
+use crate::vm::object::ObjectRef;
 
 pub(crate) fn array_load(index: Value, arrayref: Value) -> Result<Value, Error> {
     if let I32(index) = index {
         let index = index as usize;
 
-        if let Null = arrayref {
+        if let Value::Null = arrayref {
             return Err(anyhow!("NullpointerException"));
         }
         if let Ref(objectref) = arrayref {
@@ -50,6 +50,9 @@ pub(crate) fn array_load(index: Value, arrayref: Value) -> Result<Value, Error>
                 Object(_) => {
                     panic!("should be array")
                 } //throw error?
+                ObjectRef::Null => {
+                    return Ok(Value::Null);
+                }
             }
         }
     }
@@ -57,7 +60,7 @@ pub(crate) fn array_load(index: Value, arrayref: Value) -> Result<Value, Error>
 }
 
 pub(crate) fn array_store(value: Value, index: Value, arrayref: Value) -> Result<(), Error> {
-    if let Null = arrayref {
+    if let Value::Null = arrayref {
         return Err(anyhow!("NullpointerException"));
     }
 
@@ -94,9 +97,9 @@ pub(crate) fn array_store(value: Value, index: Value, arrayref: Value) -> Result
                         unreachable!()
                     }
                 }
-                CharArray(ref mut array) => unsafe {
+                CharArray(ref mut array) => {
                     if let I32(value) = value {
-                        array[index as usize] = char::from_u32_unchecked(value as u32);
+                        array[index as usize] = value
                     } else {
                         unreachable!()
                     }
@@ -136,7 +139,7 @@ pub(crate) fn array_store(value: Value, index: Value, arrayref: Value) -> Result
                         unreachable!()
                     }
                 }
-                Object(_) | Class(_) => {} //throw error?
+                Object(_) | Class(_) | ObjectRef::Null => {} //throw error?
             }
         }
     } else {

src/vm/mod.rs

@@ -1,4 +1,5 @@
 mod array;
+mod native;
 pub(crate) mod object;
 pub(crate) mod opcodes;
 pub mod runtime;

src/vm/native.rs

@@ -0,0 +1,243 @@
+#![allow(non_snake_case)]
+
+use std::cell::RefCell;
+use std::collections::HashMap;
+use std::rc::Rc;
+
+use anyhow::Error;
+use log::debug;
+use once_cell::sync::Lazy;
+
+use crate::classmanager::ClassManager;
+use crate::value::Value;
+use crate::value::Value::{Utf8, Void, I32};
+use crate::vm::object::ObjectRef::Object;
+use crate::vm::object::{self, Array, ObjectRef};
+use crate::vm::runtime::Stackframe;
+
+const primitive_name_classes: Lazy<HashMap<&str, &str>> = Lazy::new(|| {
+    let mut mapping = HashMap::new();
+    mapping.insert("B", "byte");
+    mapping.insert("S", "short");
+    mapping.insert("I", "int");
+    mapping.insert("J", "long");
+    mapping.insert("F", "float");
+    mapping.insert("D", "double");
+    mapping.insert("C", "char");
+    mapping.insert("Z", "boolean");
+    mapping
+});
+static mut PRIMITIVE_CLASSES: Lazy<HashMap<String, Value>> = Lazy::new(|| HashMap::new());
+
+pub fn invoke_native(
+    class_manager: &mut ClassManager,
+    class_name: &str,
+    method_name: &str,
+    args: Vec<Value>,
+) -> Result<Value, Error> {
+    debug!("native {}.{}", class_name, method_name);
+
+    match class_name {
+        "java/lang/Class" => java_lang_Class(class_manager, method_name, args),
+        "java/lang/Object" => java_lang_Object(method_name, args),
+        "java/lang/System" => java_lang_System(method_name),
+        "jdk/internal/misc/Unsafe" => jdk_internal_misc_Unsafe(method_name),
+        "jdk/internal/util/SystemProps$Raw" => {
+            jdk_internal_util_SystemProps_Raw(class_manager, method_name)
+        }
+        _ => unimplemented!("{}", class_name),
+    }
+}
+
+fn java_lang_Class(
+    class_manager: &mut ClassManager,
+    method_name: &str,
+    args: Vec<Value>,
+) -> Result<Value, Error> {
+    Ok(match method_name {
+        "desiredAssertionStatus0(Ljava/lang/Class;)Z" => Value::BOOL(false),
+        "getPrimitiveClass(Ljava/lang/String;)Ljava/lang/Class;" => {
+            get_primitive_class(class_manager, args)
+        }
+        _ => Void,
+    })
+}
+
+fn java_lang_Object(method_name: &str, args: Vec<Value>) -> Result<Value, Error> {
+    Ok(match method_name {
+        "hashCode()I" => {
+            if let Value::Ref(object_ref) = args.get(0).unwrap() {
+                if let Object(p) = object_ref {
+                    I32(p.borrow().id as i32) // system hashcode
+                } else {
+                    I32(0) //todo implement for arrays
+                }
+            } else {
+                unreachable!()
+            }
+        }
+        _ => {
+            unimplemented!("{}", method_name);
+        }
+    })
+}
+
+fn java_lang_System(method_name: &str) -> Result<Value, Error> {
+    Ok(match method_name {
+        _ => Void,
+    })
+}
+
+fn get_primitive_class(class_manager: &mut ClassManager, args: Vec<Value>) -> Value {
+    if let Utf8(primitive) = args.get(0).unwrap().to_owned() {
+        unsafe {
+            PRIMITIVE_CLASSES
+                .entry(primitive.clone())
+                .or_insert_with(|| {
+                    let cls = class_manager.get_class_by_name("java/lang/Class").unwrap();
+                    let mut instance = object::Object::new(cls);
+                    instance.set(
+                        cls,
+                        "java/lang/Class",
+                        primitive_name_classes.get(primitive.as_str()).unwrap(),
+                        Utf8("name".into()),
+                    );
+                    Value::Ref(Object(Rc::new(RefCell::new(instance))))
+                });
+        }
+    }
+
+    Value::Null
+}
+
+fn jdk_internal_misc_Unsafe(method_name: &str) -> Result<Value, Error> {
+    Ok(match method_name {
+        "arrayBaseOffset0(Ljava/lang/Class;)I" => I32(0), //TODO surely this is not right
+        "arrayIndexScale0(Ljava/lang/Class;)I" => I32(0), //TODO surely this is not right
+        _ => Void,
+    })
+}
+
+fn jdk_internal_util_SystemProps_Raw(
+    class_manager: &mut ClassManager,
+    method_name: &str,
+) -> Result<Value, Error> {
+    match method_name {
+        "platformProperties()[Ljava/lang/String;" => platformProperties(),
+        "cmdProperties()Ljava/util/HashMap;" => cmdProps(class_manager), //TODO ability to instantiate classes here
+        "vmProperties()[Ljava/lang/String;" => vmProperties(),
+        _ => Ok(Void),
+    }
+}
+
+fn cmdProps(class_manager: &mut ClassManager) -> Result<Value, Error> {
+    class_manager.load_class_by_name("java/util/HashMap");
+    let hashmap_class = class_manager
+        .get_class_by_name("java/util/HashMap")
+        .unwrap();
+    let hashmap = Value::Ref(Object(Rc::new(RefCell::new(object::Object::new(
+        hashmap_class,
+    ))))); // this is convoluted
+    Stackframe::new(vec![hashmap.clone()]).run(class_manager, hashmap_class.id, "<init>()V");
+    Ok(hashmap)
+}
+
+fn vmProperties() -> Result<Value, Error> {
+    let props: Lazy<Vec<String>> = Lazy::new(|| {
+        let vec: Vec<String> = Vec::new();
+        //TODO insert some values
+        vec
+    });
+    Ok(Value::Ref(ObjectRef::StringArray(Array::from_vec(
+        props.to_vec(),
+    ))))
+}
+
+fn platformProperties() -> Result<Value, Error> {
+    let props: Lazy<Vec<String>> = Lazy::new(|| {
+        let mut vec: Vec<String> = Vec::new();
+        //TODO set correct values
+        vec.push("display_country".into()); //null in jdk21
+        vec.push("display_language".into()); //null in jdk21
+        vec.push("display_script".into()); //null in jdk21
+        vec.push("display_variant".into()); //null in jdk21
+        vec.push("UTF-8".into());
+
+        {
+            #[cfg(target_family = "unix")]
+            vec.push("/".into());
+            #[cfg(target_family = "windows")]
+            vec.push("\\");
+        }
+        vec.push("format_country".into()); //null in jdk21
+        vec.push("format_language".into()); //null in jdk21
+        vec.push("format_script".into()); //null in jdk21
+        vec.push("format_variant".into()); //null in jdk21
+        vec.push("ftp_nonProxyHosts".into());
+        if let Ok(ftp_proxy) = std::env::var("ftp_proxy") {
+            vec.push(ftp_proxy.to_owned()); //TODO
+            vec.push(ftp_proxy);
+        } else {
+            vec.push("".to_owned());
+            vec.push("".to_owned());
+        }
+
+        vec.push("http_nonProxyHosts".into());
+        if let Ok(http_proxy) = std::env::var("http_proxy") {
+            vec.push(http_proxy.to_owned());
+            vec.push(http_proxy); //TODO
+        } else {
+            vec.push("".to_owned());
+            vec.push("".to_owned());
+        }
+        if let Ok(https_proxy) = std::env::var("https_proxy") {
+            vec.push(https_proxy.to_owned());
+            vec.push(https_proxy);
+        } else {
+            vec.push("".to_owned());
+            vec.push("".to_owned());
+        }
+        vec.push(std::env::temp_dir().display().to_string());
+
+        {
+            #[cfg(target_family = "unix")]
+            vec.push("\n".into());
+            #[cfg(target_family = "windows")]
+            vec.push("\r\n");
+        }
+        vec.push(whoami::platform().to_string());
+        vec.push(whoami::devicename());
+        vec.push("os_version".into());
+        {
+            #[cfg(target_family = "unix")]
+            vec.push(":".into());
+            #[cfg(target_family = "windows")]
+            vec.push(";".into());
+        }
+        vec.push("socksNonProxyHosts".into());
+        vec.push("socksProxyHost".into());
+        vec.push("socksProxyPort".into());
+        vec.push("UTF-8".into());
+        vec.push("UTF-8".into());
+        vec.push("sun_arch_abi".into());
+        vec.push("sun_arch_data_model".into());
+        vec.push("sun_cpu_endian".into()); //null in jdk21
+        vec.push("sun_cpu_isalist".into()); //null in jdk21
+        vec.push("sun_io_unicode_encoding".into()); //null in jdk21
+        vec.push("sun_jnu_encoding".into()); //null in jdk21
+        vec.push("sun_os_patch_level".into()); //null in jdk21
+        if let Ok(curdir) = std::env::current_dir() {
+            vec.push(curdir.display().to_string());
+        }
+
+        let home = std::env::home_dir().unwrap();
+        vec.push(home.display().to_string());
+        vec.push(whoami::username());
+        vec.push("FIXED_LENGTH".into());
+
+        vec
+    });
+    Ok(Value::Ref(ObjectRef::StringArray(Array::from_vec(
+        props.to_vec(),
+    ))))
+}

src/vm/object.rs

@@ -1,25 +1,100 @@
-use std::cell::RefCell;
-use std::rc::Rc;
+use crate::class::{Class, ClassId};
+use crate::value::Value;
+use crate::vm::object::ObjectRef::*;
 use log::debug;
 use rand::random;
-use crate::class::{Class, ClassId};
-use crate::vm::object::ObjectRef::*;
-use crate::value::Value;
+use std::cell::RefCell;
+use std::fmt::{Debug, Formatter, Pointer};
+use std::rc::Rc;
 
-#[derive(Debug, Clone)]
+#[derive(Clone, PartialEq)]
+pub struct Array<T>
+where
+    T: Clone,
+{
+    id: u32,
+    data: Vec<T>,
+}
+
+impl<T> Array<T>
+where
+    T: Clone,
+{
+    pub fn new(init: T, size: usize) -> Self {
+        Self {
+            id: random::<u32>() >> 1,
+            data: vec![init; size],
+        }
+    }
+
+    pub fn from_vec(vec: Vec<T>) -> Self {
+        Self {
+            id: random::<u32>() >> 1,
+            data: vec,
+        }
+    }
+    pub fn len(&self) -> usize {
+        self.data.len()
+    }
+}
+
+impl<T> std::ops::Index<usize> for Array<T>
+where
+    T: Clone,
+{
+    type Output = T;
+
+    fn index(&self, index: usize) -> &Self::Output {
+        &self.data[index]
+    }
+}
+
+impl<T> std::ops::IndexMut<usize> for Array<T>
+where
+    T: Clone,
+{
+    fn index_mut(&mut self, index: usize) -> &mut Self::Output {
+        &mut self.data[index]
+    }
+}
+
+#[derive(Clone, PartialEq)]
 pub enum ObjectRef {
-    ByteArray(Vec<i8>),
-    ShortArray(Vec<i16>),
-    IntArray(Vec<i32>),
-    LongArray(Vec<i64>),
-    FloatArray(Vec<f32>),
-    DoubleArray(Vec<f64>),
-    BooleanArray(Vec<bool>),
-    CharArray(Vec<char>),
-    StringArray(Vec<String>),
+    ByteArray(Array<i8>),
+    //maybe use arrays?
+    ShortArray(Array<i16>),
+    IntArray(Array<i32>),
+    LongArray(Array<i64>),
+    FloatArray(Array<f32>),
+    DoubleArray(Array<f64>),
+    BooleanArray(Array<bool>),
+    CharArray(Array<i32>),
+    StringArray(Array<String>),
     ObjectArray(ClassId, Vec<ObjectRef>),
     Object(Rc<RefCell<Object>>),
     Class(Class),
+    Null,
+}
+
+impl Debug for ObjectRef {
+    fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
+        let name = match self {
+            ByteArray(a) => format!("[B;{}", a.len()),
+            ShortArray(a) => format!("[S;{}", a.len()),
+            IntArray(a) => format!("[I;{}", a.len()),
+            LongArray(a) => format!("[J;{}", a.len()),
+            FloatArray(a) => format!("[F;{}", a.len()),
+            DoubleArray(a) => format!("[D;{}", a.len()),
+            BooleanArray(a) => format!("[Z;{}", a.len()),
+            CharArray(a) => format!("[C;{}", a.len()),
+            StringArray(a) => format!("[Ljava/lang/String;{}]", a.len()),
+            ObjectArray(_, a) => format!("[[Lx;{}]", a.len()),
+            Object(_) => "L".into(),
+            Class(_) => "Class".into(),
+            ObjectRef::Null => "null".into(),
+        };
+        write!(f, "{}", name)
+    }
 }
 
 impl ObjectRef {
@@ -35,7 +110,7 @@ impl ObjectRef {
             CharArray(d) => d.len(),
             StringArray(d) => d.len(),
             ObjectArray(_, d) => d.len(),
-            _ => unreachable!("not an array {:?}", self)
+            _ => unreachable!("not an array {:?}", self),
         }
     }
 }
@@ -53,29 +128,29 @@ pub enum ArrayType {
 
 impl ObjectRef {
     pub fn new_object_array(class: &Class, size: usize) -> Self {
-        ObjectArray(class.id, Vec::with_capacity(size))
+        ObjectArray(class.id, vec![ObjectRef::Null; size])
     }
 
     pub fn new_array(arraytype: u8, size: usize) -> Self {
         match arraytype {
-            8 => ByteArray(Vec::with_capacity(size)),
-            9 => ShortArray(Vec::with_capacity(size)),
-            10 => IntArray(Vec::with_capacity(size)),
-            11 => LongArray(Vec::with_capacity(size)),
-            6 => FloatArray(Vec::with_capacity(size)),
-            7 => DoubleArray(Vec::with_capacity(size)),
-            4 => BooleanArray(Vec::with_capacity(size)),
-            5 => CharArray(Vec::with_capacity(size)),
-            _ => unreachable!("impossible array type")
+            8 => ByteArray(Array::new(0, size)),
+            9 => ShortArray(Array::new(0, size)),
+            10 => IntArray(Array::new(0, size)),
+            11 => LongArray(Array::new(0, size)),
+            6 => FloatArray(Array::new(0_f32, size)),
+            7 => DoubleArray(Array::new(0_f64, size)),
+            4 => BooleanArray(Array::new(false, size)),
+            5 => CharArray(Array::new(0, size)),
+            _ => unreachable!("impossible array type"),
         }
     }
 
     pub fn new_int_array(size: usize) -> Self {
-        IntArray(Vec::with_capacity(size))
+        IntArray(Array::new(0, size))
     }
 
     pub fn new_byte_array(d: Vec<u8>) -> Self {
-        ByteArray(into_vec_i8(d))
+        ByteArray(Array::from_vec(into_vec_i8(d)))
     }
 }
 
@@ -101,12 +176,18 @@ pub struct Object {
     pub data: Vec<Value>,
 }
 
+impl PartialEq for Object {
+    fn eq(&self, other: &Self) -> bool {
+        self.id == other.id
+    }
+}
+
 // object, not array
 impl Object {
     pub fn new(class: &Class) -> Self {
         let instance_data = Object::init_fields(class);
         Self {
-            id: random(),
+            id: random::<u32>() >> 1,
             class_id: class.id,
             data: instance_data,
         }
@@ -135,7 +216,13 @@ impl Object {
         field_data
     }
 
-    pub fn set(&mut self, runtime_type: &Class, declared_type: &str, field_name: &str, value: Value) {
+    pub fn set(
+        &mut self,
+        runtime_type: &Class,
+        declared_type: &str,
+        field_name: &str,
+        value: Value,
+    ) {
         debug!("set {:?}.{}", runtime_type.name, field_name);
         let type_index = runtime_type
             .object_field_mapping
@@ -153,7 +240,10 @@ impl Object {
             .unwrap()
             .get(field_name)
             .unwrap();
-        debug!("get {:?}:{}.{}:{} @{}", runtime_type, declared_type, field_name, type_index.type_name, type_index.index);
+        debug!(
+            "get {:?}:{}.{}:{} @{}",
+            runtime_type, declared_type, field_name, type_index.type_name, type_index.index
+        );
         debug!("from data {:?}", self.data);
         self.data.get(type_index.index).unwrap()
     }

src/vm/opcodes.rs

@@ -85,20 +85,22 @@ pub(crate) enum Opcode {
     LSHL,
     ISHR,
     LSHR,
+    IUSHR,
+    LUSHR,
     IAND,
     LAND,
     IOR,
     LOR,
     IXOR,
     LXOR,
-    IINC(u8,u8),
+    IINC(u8, u8),
     I2L,
     I2F,
     I2D,
     L2I,
     L2F,
     L2D,
-    WIDE_IINC(u16,u16),
+    WIDE_IINC(u16, u16),
     F2I,
     F2L,
     F2D,
@@ -134,6 +136,7 @@ pub(crate) enum Opcode {
     TABLESWITCH(Tableswitch),
     LOOKUPSWITCH(Lookupswitch),
     IRETURN,
+    LRETURN,
     FRETURN,
     DRETURN,
     ARETURN,
@@ -162,7 +165,4 @@ pub(crate) enum Opcode {
     IFNONNULL(u16),
     GOTOW(i32),
     JSR_W(i32),
-
 }
-
-

tests/class_tests.rs

@@ -1,18 +1,23 @@
 mod test {
     use java_rs::vm::runtime::Vm;
 
-
-
     #[test]
     fn if_cmp() {
         let vm = Vm::new();
-        vm.run("/Users/Shautvast/dev/java/tests", "testclasses.IfCmp", "i_is_1()Z");
+        vm.run(
+            "/Users/Shautvast/dev/java/tests",
+            "testclasses.IfCmp",
+            "i_is_1()Z",
+        );
     }
 
     #[test]
     fn consts() {
-
         let vm = Vm::new();
-        vm.run("/Users/Shautvast/dev/java/tests", "testclasses.Const", "hello()Ljava/lang/String;")
+        vm.run(
+            "/Users/Shautvast/dev/java/tests",
+            "testclasses.Const",
+            "hello()Ljava/lang/String;",
+        )
     }
 }

tests/method_tests.rs

@@ -1,7 +1,7 @@
 mod test {
+    use java_rs::classloader::classdef::{Method, Modifier};
     use std::collections::HashMap;
     use std::rc::Rc;
-    use java_rs::classloader::classdef::{Method, Modifier};
 
     #[test]
     fn access_flags() {
@@ -11,13 +11,10 @@ mod test {
             0,
             0,
             HashMap::new(),
+            vec![],
         );
         assert!(m.is(Modifier::Public));
         assert!(m.is(Modifier::Static));
         assert!(!m.is(Modifier::Private));
     }
-
-
-
-
 }