JVM assembler/disassembler tested to work on Hello.java.

[hs-java.git] / rebuild-class.hs

diff --git a/rebuild-class.hs b/rebuild-class.hs
new file mode 100644 (file)
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--- /dev/null
+++ b/rebuild-class.hs
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+{-# LANGUAGE OverloadedStrings #-}
+
+import Control.Monad
+import Data.Array
+import Data.Binary
+import System.Environment
+import qualified Data.ByteString.Lazy as B
+import Text.Printf
+
+import JVM.Types
+import JVM.ClassFile
+import JVM.Converter
+import JVM.Assembler
+
+main = do
+  args <- getArgs
+  case args of
+    [clspath,outpath] -> do
+      cls <- parseClassFile clspath
+      clsfile <- decodeFile clspath :: IO ClassFile
+      putStr "Class: "
+      B.putStrLn (this cls)
+      putStrLn "Constants pool:"
+      forM_ (assocs $ constantPool cls) $ \(i, c) ->
+        putStrLn $ printf "  #%d:\t%s" i (show c)
+      putStrLn "Methods:"
+      forM_ (methods cls) $ \m -> do
+        putStr ">> Method "
+        B.putStr (methodName m)
+        print (methodSignature m)
+        case attrByName m "Code" of
+          Nothing -> putStrLn "(no code)\n"
+          Just bytecode -> let code = decodeMethod bytecode
+                           in  forM_ (codeInstructions code) $ \i -> do
+                                 putStr "  "
+                                 print i
+      putStrLn $ "Source pool:\n" ++ showListIx (constsPool clsfile)
+      let result = classFile cls
+      putStrLn $ "Result pool:\n" ++ showListIx (constsPool result)
+      B.writeFile outpath (encodeClass cls)
+
+    _ -> error "Synopsis: rebuild-class File.class Output.class"