src/gen_java.ml

   1 (* Java code generation *)
   2
   3 open ExtLib
   4 open Prelude
   5 open Printf
   6
   7 open Stmt
   8 open Gen
   9 open Sql
  10
  11 module G = Gen_cxx
  12
  13 let comment = G.comment
  14 let empty_line = G.empty_line
  15
  16 let quote = String.replace_chars (function '\n' -> "\" +\n\"" | '\r' -> "" | '"' -> "\\\"" | c -> String.make 1 c)
  17 let quote s = "\"" ^ quote s ^ "\""
  18
  19 let start_ cls =
  20    let f1 name =
  21    output "%s %s" cls name;
  22    G.open_curly ()
  23    in
  24    let f2 name =
  25    G.close_curly " // %s %s" cls name;
  26    empty_line ()
  27    in
  28    f1,f2
  29
  30 let (start_class,end_class) = start_ "public class"
  31 let (start_intf,end_intf) = start_ "public static interface"
  32
  33 module L = struct
  34
  35 let as_lang_type = function
  36   | Type.Int -> "int"
  37   | Type.Text -> "String"
  38   | Type.Any -> "String"
  39   | Type.Float -> "float"
  40   | Type.Blob -> "Blob"
  41   | Type.Bool -> "boolean"
  42   | Type.Datetime -> "Timestamp"
  43
  44 let as_api_type = String.capitalize $ as_lang_type
  45
  46 end
  47
  48 module T = Translate(L)
  49
  50 open L
  51 open T
  52
  53 let get_column attr index =
  54   sprintf "res.get%s(%u)"
  55     (attr.domain |> as_api_type)
  56     (index + 1)
  57
  58 let output_schema_binder name _ schema =
  59   let name = sprintf "%s_callback" name in
  60   start_intf name;
  61   output "public void callback(%s);" (G.Values.to_string (schema_to_values schema));
  62   end_intf name;
  63   name
  64
  65 let output_schema_binder name index schema =
  66   match schema with
  67   | [] -> None
  68   | _ -> Some (output_schema_binder name index schema)
  69
  70 let output_value_defs vals =
  71   vals |> List.iter (fun (name,t) -> output "%s %s;" t name)
  72
  73 let output_schema_data index schema =
  74   let name = default_name "data" index in
  75   start_class name;
  76   schema |> schema_to_values |> output_value_defs;
  77   end_class name
  78
  79 let set_param name index param =
  80   let (id,t) = param in
  81   output "pstmt_%s.set%s(%u, %s);"
  82     name
  83     (t |> param_type_to_string |> String.capitalize)
  84     (index+1)
  85     (param_name_to_string id index)
  86
  87 let output_params_binder name _ params = List.iteri (set_param name) params
  88
  89 type t = unit
  90
  91 let start () = ()
  92
  93 let generate_code index stmt =
  94    let values = params_to_values stmt.params in
  95    let name = choose_name stmt.props stmt.kind index in
  96    let sql = quote (get_sql stmt) in
  97    output "PreparedStatement pstmt_%s;" name;
  98    empty_line ();
  99    let schema_binder_name = output_schema_binder name index stmt.schema in
 100    let result = match schema_binder_name with None -> [] | Some name -> ["result",name] in
 101    let all_params = values @ result in
 102    G.func "public int" name all_params ~tail:"throws SQLException" (fun () ->
 103       output "if (null == pstmt_%s)" name;
 104       output "  pstmt_%s = db.prepareStatement(%s);" name sql;
 105       output_params_binder name index stmt.params;
 106       begin match schema_binder_name with
 107       | None -> output "return pstmt_%s.executeUpdate();" name
 108       | Some _ ->
 109          output "ResultSet res = pstmt_%s.executeQuery();" name;
 110          let args = List.mapi (fun index attr -> get_column attr index) stmt.schema in
 111          let args = String.concat "," args in
 112          output "int count = 0;";
 113          output "while (res.next())";
 114          G.open_curly ();
 115          output "result.callback(%s);" args;
 116          output "count++;";
 117          G.close_curly "";
 118          output "return count;"
 119       end);
 120     empty_line ()
 121
 122 let generate () name stmts =
 123   params_mode := Some Unnamed; (* allow only unnamed params *)
 124   output "import java.sql.*;";
 125   empty_line ();
 126   start_class name;
 127   output "Connection db;";
 128   empty_line ();
 129   G.func "public" name ["aDb","Connection"] (fun () ->
 130     output "db = aDb;";
 131   );
 132   empty_line ();
 133   Enum.iteri generate_code stmts;
 134   end_class name
 135