First implementation of CLASSPATH and JAR files reading.

[hs-java.git] / JVM / ClassFile.hs

diff --git a/JVM/ClassFile.hs b/JVM/ClassFile.hs
index 0359320592a9ab1cf10aa464f795423ade56ebf4..56615c0181b03cba7d505281f1713c95dc639055 100644 (file)
--- a/JVM/ClassFile.hs
+++ b/JVM/ClassFile.hs
@@ -19,9 +19,11 @@ module JVM.ClassFile
    Constant (..),
    AccessFlag (..), AccessFlags,
    Attributes (..),
+   defaultClass,
    -- * Misc
    HasSignature (..), HasAttributes (..),
    NameType (..),
+   toString,
    className,
    apsize, arsize, arlist
   )
@@ -35,6 +37,7 @@ import Data.Binary.Get
 import Data.Binary.Put
 import Data.Char
 import Data.List
+import Data.Default
 import qualified Data.Set as S
 import qualified Data.Map as M
 import qualified Data.ByteString.Lazy as B
@@ -96,10 +99,16 @@ data family Attributes stage
 data instance Attributes File = AP {attributesList :: [Attribute]}
   deriving (Eq, Show)
 
+instance Default (Attributes File) where
+  def = AP []
+
 -- | At Direct stage, attributes are represented as a Map.
 data instance Attributes Direct = AR (M.Map B.ByteString B.ByteString)
   deriving (Eq, Show)
 
+instance Default (Attributes Direct) where
+  def = AR M.empty
+
 -- | Size of attributes set at Direct stage
 arsize :: Attributes Direct -> Int
 arsize (AR m) = M.size m
@@ -128,7 +137,8 @@ data AccessFlag =
   deriving (Eq, Show, Ord, Enum)
 
 -- | Fields and methods have signatures.
-class HasSignature a where
+class (Binary (Signature a), Show (Signature a), Eq (Signature a))
+    => HasSignature a where
   type Signature a
 
 instance HasSignature Field where
@@ -142,12 +152,12 @@ data NameType a = NameType {
   ntName :: B.ByteString,
   ntSignature :: Signature a }
 
-instance Show (Signature a) => Show (NameType a) where
+instance (HasSignature a) => Show (NameType a) where
   show (NameType n t) = toString n ++ ": " ++ show t
 
-deriving instance Eq (Signature a) => Eq (NameType a)
+deriving instance HasSignature a => Eq (NameType a)
 
-instance (Binary (Signature a)) => Binary (NameType a) where
+instance HasSignature a => Binary (NameType a) where
   put (NameType n t) = putLazyByteString n >> put t
 
   get = NameType <$> get <*> get
@@ -209,10 +219,36 @@ data Class stage = Class {
   classAttributes :: Attributes stage -- ^ Class attributes
   }
 
+deriving instance Eq (Class File)
+deriving instance Eq (Class Direct)
+deriving instance Show (Class File)
+deriving instance Show (Class Direct)
+
 deriving instance Eq (Constant File)
 deriving instance Eq (Constant Direct)
 deriving instance Show (Constant File)
 
+-- | Default (empty) class file definition.
+defaultClass :: (Default (AccessFlags stage), Default (Link stage B.ByteString), Default (Attributes stage))
+             => Class stage
+defaultClass = Class {
+  magic = 0xCAFEBABE,
+  minorVersion = 0,
+  majorVersion = 50,
+  constsPoolSize = 0,
+  constsPool = def,
+  accessFlags = def,
+  thisClass = def,
+  superClass = def,
+  interfacesCount = 0,
+  interfaces = [],
+  classFieldsCount = 0,
+  classFields = [],
+  classMethodsCount = 0,
+  classMethods = [],
+  classAttributesCount = 0,
+  classAttributes = def }
+
 instance Binary (Class File) where
   put (Class {..}) = do
     put magic