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%
% (c) The GRASP/AQUA Project, Glasgow University, 1993-1998
%
\section{Generate Java}
\begin{code}
module PrintJava( compilationUnit ) where
import Java
import Outputable
import Char( toLower )
\end{code}
\begin{code}
indent :: SDoc -> SDoc
indent = nest 2
\end{code}
%************************************************************************
%* *
\subsection{Pretty printer}
%* *
%************************************************************************
\begin{code}
compilationUnit :: CompilationUnit -> SDoc
compilationUnit (Package n ds) = package n (decls ds)
package = \n -> \ds ->
text "package" <+> packagename n <> text ";"
$$
ds
decls [] = empty
decls (d:ds) = decl d $$ decls ds
decl = \d ->
case d of
{ Import n -> importDecl (packagename n)
; Field mfs n e -> field (modifiers mfs) (nameTy n) (name n) e
; Constructor mfs n as ss -> constructor (modifiers mfs) (typename n) (parameters as) (statements ss)
; Method mfs n as ts ss -> method (modifiers mfs) (nameTy n) (name n) (parameters as) (throws ts) (statements ss)
; Comment s -> comment s
; Interface mfs n is ms -> interface (modifiers mfs) (typename n) (extends is) (decls ms)
; Class mfs n x is ms -> clazz (modifiers mfs) (typename n) (extends x) (implements is) (decls ms)
}
importDecl n = text "import" <+> n <> text ";"
field = \mfs -> \t -> \n -> \e ->
case e of
{ Nothing -> mfs <+> t <+> n <> text ";"
; Just e -> lay [mfs <+> t <+> n <+> text "=", indent (expr e <> text ";")]
where
lay | isSimple e = hsep
| otherwise = sep
}
constructor = \mfs -> \n -> \as -> \ss ->
mfs <+> n <+> parens (hsep (punctuate comma as)) <+> text "{"
$$ indent ss
$$ text "}"
method = \mfs -> \t -> \n -> \as -> \ts -> \ss ->
mfs <+> t <+> n <+> parens (hsep (punctuate comma as)) <+> ts <+> text "{"
$$ indent ss
$$ text "}"
comment = \ss ->
text "/**"
$$ indent (vcat [ text s | s <- ss])
$$ text "**/"
interface = \mfs -> \n -> \xs -> \ms ->
mfs <+> n <+> xs <+> text "{"
$$ indent ms
$$ text "}"
clazz = \mfs -> \n -> \x -> \is -> \ms ->
mfs <+> text "class" <+> n <+> x <+> is <+> text "{"
$$ indent ms
$$ text "}"
modifiers mfs = hsep (map modifier mfs)
modifier mf = text $ map toLower (show mf)
extends [] = empty
extends xs = text "extends" <+> hsep (punctuate comma (map typename xs))
implements [] = empty
implements xs = text "implements" <+> hsep (punctuate comma (map typename xs))
throws [] = empty
throws xs = text "throws" <+> hsep (punctuate comma (map typename xs))
name (Name n t) = text n
nameTy (Name n t) = typ t
typename n = text n
packagename n = text n
parameters as = map parameter as
parameter (Parameter mfs n) = modifiers mfs <+> nameTy n <+> name n
typ (PrimType s) = primtype s
typ (Type n) = typename n
typ (ArrayType t) = typ t <> text "[]"
primtype PrimInt = text "int"
primtype PrimBoolean = text "boolean"
primtype PrimChar = text "char"
primtype PrimLong = text "long"
primtype PrimFloat = text "float"
primtype PrimDouble = text "double"
primtype PrimByte = text "byte"
primtype PrimVoid = text "void"
statements ss = vcat (map statement ss)
statement = \s ->
case s of
{ Skip -> skip
; Return e -> returnStat (expr e)
; Block ss -> vcat [statement s | s <- ss]
; ExprStatement e -> exprStatement (expr e)
; Declaration d -> declStatement (decl d)
; IfThenElse ecs s -> ifthenelse [ (expr e, statement s) | (e,s) <- ecs ] (maybe Nothing (Just .statement) s)
; Switch e as d -> switch (expr e) (arms as) (deflt d)
}
skip = empty
returnStat e = sep [text "return", indent e <> semi]
exprStatement e = e <> semi
declStatement d = d
ifthenelse ((e,s):ecs) ms = sep [ text "if" <+> parens e <+> text "{",
indent s,
thenelse ecs ms]
thenelse ((e,s):ecs) ms = sep [ text "} else if" <+> parens e <+> text "{",
indent s,
thenelse ecs ms]
thenelse [] Nothing = text "}"
thenelse [] (Just s) = sep [text "} else {", indent s, text "}"]
switch = \e -> \as -> \d ->
text "switch" <+> parens e <+> text "{"
$$ indent (as $$ d)
$$ text "}"
deflt Nothing = empty
deflt (Just ss) = text "default:" $$ indent (statements ss)
arms [] = empty
arms ((e,ss):as) = text "case" <+> expr e <> colon
$$ indent (statements ss)
$$ arms as
maybeExpr Nothing = Nothing
maybeExpr (Just e) = Just (expr e)
expr = \e ->
case e of
{ Var n -> name n
; Literal l -> literal l
; Cast t e -> cast (typ t) e
; Access e n -> expr e <> text "." <> name n
; Assign l r -> assign (expr l) r
; New n es ds -> new (typ n) es (maybeClass ds)
; Raise n es -> text "raise" <+> text n
<+> parens (hsep (punctuate comma (map expr es)))
; Call e n es -> call (expr e) (name n) es
; Op e1 o e2 -> op e1 o e2
; InstanceOf e t -> expr e <+> text "instanceof" <+> typ t
}
op = \e1 -> \o -> \e2 ->
( if isSimple e1
then expr e1
else parens (expr e1)
)
<+>
text o
<+>
( if isSimple e2
then expr e2
else parens (expr e2)
)
assign = \l -> \r ->
if isSimple r
then l <+> text "=" <+> (expr r)
else l <+> text "=" $$ indent (expr r)
cast = \t -> \e ->
if isSimple e
then parens (parens t <> expr e)
else parens (parens t $$ indent (expr e))
new n [] (Just ds) = sep [text "new" <+> n <+> text "()" <+> text "{",
indent ds,
text "}"]
new n es Nothing = text "new" <+> n <> parens (hsep (punctuate comma (map expr es)))
call e n es = e <> dot <> n <> parens (hsep (punctuate comma (map expr es)))
literal = \l ->
case l of
{ IntLit i -> text (show i)
; CharLit c -> text "(char)" <+> text (show c)
; StringLit s -> text ("\"" ++ s ++ "\"") -- strings are already printable
}
maybeClass Nothing = Nothing
maybeClass (Just ds) = Just (decls ds)
\end{code}
|
