Slight refactoring

src/main.rs

@@ -47,7 +47,7 @@ fn main() {
     };
 
     println!(
-        "result={}",
+        "\nresult={}",
         result.map_or_else(|| "<empty>".to_string(), |v| v.to_string())
     );
 }

vm/src/class_loader.rs

@@ -29,19 +29,16 @@ impl ClassLoader {
         let std_class_names = Self::get_class_files_in_dir(std_dir)?;
 
         for path in std_class_names {
-            let class = Self::load_class(path.to_str().ok_or(Error::new_io(io::Error::new(
-                Other,
-                "error getting path".to_string(),
-            )))?)?;
+            let (class_name, java_class) = Self::load_class(path.to_str().ok_or(
+                Error::new_io(io::Error::new(Other, "error getting path".to_string())),
+            )?)?;
 
-            loaded_classes.insert(class.0, class.1);
+            loaded_classes.insert(class_name, java_class);
         }
 
-        let mut classes: Vec<String> = vec![];
         for class_file_name in class_file_names {
-            let class = Self::load_class(class_file_name)?;
-            loaded_classes.insert(class.0.clone(), class.1);
-            classes.push(class.0);
+            let (class_name, java_class) = Self::load_class(class_file_name)?;
+            loaded_classes.insert(class_name.clone(), java_class);
         }
 
         Ok(Self {
@@ -87,17 +84,17 @@ impl ClassLoader {
                 .ok_or(Error::new_constant_pool(
                     "Error getting method method_signature",
                 ))?;
-            let code = Self::get_cpool_code_attribute(method.attributes())
+            let (max_stack, max_locals, code) = Self::get_cpool_code_attribute(method.attributes())
                 .ok_or(Error::new_constant_pool("Error getting method code"))?;
             let key_signature = method_name + ":" + method_signature.as_str();
 
             method_by_signature.insert(
                 key_signature.clone(),
                 JavaMethod::new(
                     Signature::from_str(method_signature.as_str())?,
-                    code.0,
-                    code.1,
-                    code.2,
+                    max_stack,
+                    max_locals,
+                    code,
                     class_name,
                 ),
             );

vm/src/method_area/method_area.rs

@@ -61,7 +61,7 @@ impl MethodArea {
         let cpool = java_class.class_file.constant_pool();
 
         // Retrieve Methodref from the constant pool
-        let methodref = cpool
+        let (class_index, name_and_type_index) = cpool
             .get(methodref_cpool_index as usize)
             .and_then(|entry| match entry {
                 Methodref {
@@ -81,21 +81,22 @@ impl MethodArea {
             })?;
 
         // Retrieve class name from the constant pool
-        let class_name = get_class_name_by_cpool_class_index(methodref.0, &java_class.class_file);
+        let class_name = get_class_name_by_cpool_class_index(class_index, &java_class.class_file);
 
         // Retrieve method name and signature from the constant pool
         let (method_name, method_signature) = if let NameAndType {
             name_index,
             descriptor_index,
-        } = cpool.get(methodref.1).ok_or_else(|| {
-            Error::new_constant_pool(
-                format!(
-                    "Invalid NameAndType reference at index {} in class {:?}",
-                    methodref_cpool_index, java_class
+        } =
+            cpool.get(name_and_type_index).ok_or_else(|| {
+                Error::new_constant_pool(
+                    format!(
+                        "Invalid NameAndType reference at index {} in class {:?}",
+                        methodref_cpool_index, java_class
+                    )
+                    .as_str(),
                 )
-                .as_str(),
-            )
-        })? {
+            })? {
             let name = get_cpool_string(&java_class.class_file, *name_index as usize);
             let signature = get_cpool_string(&java_class.class_file, *descriptor_index as usize);
             (name, signature)
@@ -122,7 +123,7 @@ impl MethodArea {
         let cpool = java_class.class_file.constant_pool();
 
         // Retrieve Fieldref from the constant pool
-        let fieldref = cpool
+        let (class_index, name_and_type_index) = cpool
             .get(fieldref_cpool_index as usize)
             .and_then(|entry| match entry {
                 Fieldref {
@@ -142,13 +143,13 @@ impl MethodArea {
             })?;
 
         // Retrieve class name from the constant pool
-        let class_name = get_class_name_by_cpool_class_index(fieldref.0, &java_class.class_file);
+        let class_name = get_class_name_by_cpool_class_index(class_index, &java_class.class_file);
 
         // Retrieve field name from the constant pool
         let field_name = if let NameAndType {
             name_index,
             descriptor_index: _,
-        } = cpool.get(fieldref.1).ok_or_else(|| {
+        } = cpool.get(name_and_type_index).ok_or_else(|| {
             Error::new_constant_pool(
                 format!(
                     "Invalid NameAndType reference at index {} in class {:?}",