It have two reports:
zjavacreate
zjavamodify

ZJAVACREATE:

REPORT  zjavacreate message-id zmsgnew.

*************************Creation of Internal table*******************
DATA: BEGIN OF ti_record OCCURS 200,
Line(250),
END OF ti_record.
DATA: BEGIN OF ti_rec OCCURS 200,
Line(250),
END OF ti_rec.

******************************Selection screen*************************
selection-screen begin of block b1 with frame .
Parameters create radiobutton group g1.
PARAMETERS: JavaName(30) lower case.
parameters modify radiobutton group g1.
selection-screen end of block b1.

*******************Calling the java program creation page***************
at selection-screen.
  if CREATE = 'X'.
    if javaname is not initial.
      refresh ti_record[].
   concatenate 'public class' javaname into ti_record-line separated by space.

   concatenate ti_record-line '{' into ti_record-line separated by space.
      Append ti_record.
      ti_record-line = 'public static void main(String []args){'.
      Append ti_record.
      ti_record-line ='//enter ur code here'.
      append ti_record.
      ti_record-line ='}'.
      Append ti_record.
      ti_record-line ='}'.
      Append ti_record.

      EDITOR-CALL FOR ti_record .
    else.
      Message e001.

    endif.
***************************Saving the java program*********************
data tfile type string.

concatenate 'D:\Programs\' javaname '.java' into tfile.
CALL FUNCTION 'GUI_DOWNLOAD'
  EXPORTING
    FILENAME                        = tfile
    FILETYPE                        = 'ASC'
  TABLES
    DATA_TAB                        =   ti_record.
  endif.
data new(15).
  if MODIFY = 'X'.
    new = 'ZJAVAMODIFY1'.
    CALL TRANSACTION NEW.
  endif.
*****************************************************************************************

ZJAVAMODIFY:

REPORT  zjavamodify.
***********************selection screen.*********************
selection-screen begin of block b1 with frame .
Parameters compile radiobutton group g1.
Parameters modify radiobutton group g1.
Parameters execute radiobutton group g1.
PARAMETER : FILE(100) lower case.
selection-screen end of block b1.
DATA: BEGIN OF TI_RECORD OCCURS 1,
LINE(200),
END OF TI_RECORD.
data: st1(30),st2(30).

AT SELECTION-SCREEN ON VALUE-REQUEST FOR FILE.
  CALL FUNCTION 'WS_FILENAME_GET'
    EXPORTING
*     DEF_FILENAME           = ' '
      DEF_PATH               = '*.*'
*     MASK                   = ' '
*     MODE                   = ' '
*     TITLE                  = ' '
    IMPORTING
      FILENAME               = FILE
*     RC                     =
           .

End-of-selection.

********************************************************************
*****************************MODIFY*********************************
  if modify = 'X'.
    data: TXT_FILE1 TYPE STRING .
    txt_file1 = file.
**************FM GUI_UPLOAD

    CALL FUNCTION 'GUI_UPLOAD'
      EXPORTING
        FILENAME = txt_file1
      TABLES
        DATA_TAB = ti_recORD[].
**********End FM GUI_UPLOAD
    EDITOR-CALL FOR ti_record .
**************FM GUI_UPLOAD

    CALL FUNCTION 'GUI_DOWNLOAD'
      EXPORTING
        FILENAME = txt_file1
        FILETYPE = 'ASC'
      TABLES
        DATA_TAB = ti_record.
**********End FM GUI_UPLOAD
  endif.

********************end of modify********************

*******************BAT file for compilation n 
execution.****************
  if compile = 'X'.
    DATA: begin of itab_bat_create occurs 0,
       row(500) type c,
      end of itab_bat_create.

    data:comp_join1(250).
    concatenate 'java' 'jCompiler' file into comp_join1
     separated
     by space.
    itab_bat_create-row = 'c:'.
    append itab_bat_create.
    itab_bat_create-row = 'cd Documents and Settings\127740'.
    append itab_bat_create.
    itab_bat_create-row = comp_join1.
    append itab_bat_create.

********FM GUI_DOWNLOAD
    data: st type string.
    st = 'C:\Documents and Settings\127740\compile_java.bat'.
    call function 'GUI_DOWNLOAD'
      EXPORTING
        filename         = st
        filetype         = 'ASC'
      TABLES
        data_tab         = itab_bat_create[]
      EXCEPTIONS
        file_open_error  = 1
        file_write_error = 2
        others           = 3.
********end FM GUI_DOWNLOAD
*****FM dvsvas_doc_ws_execute_50
    CALL FUNCTION 'DSVAS_DOC_WS_EXECUTE_50'
      EXPORTING
        PROGRAM = 'C:\Documents and Settings\127740\compile_java.bat'.
*****end FM dvsvas_doc_ws_execute_50
  endif.
************************end of compile********************************

*********************************************************************
*************************************** output***********************
  if execute = 'X'.
    data: TXT_FILE3 TYPE STRING .
    split File AT '.java' into: st1 st2  .
    concatenate st1 'error.txt' into TXT_FILE3.
**************FM GUI_UPLOAD
    CALL FUNCTION 'GUI_UPLOAD'
      EXPORTING
        FILENAME = txt_file3
      TABLES
        DATA_TAB = ti_recORD[].
**********End FM GUI_UPLOAD
    if not ti_record[] is initial.
      loop at ti_record.
        write:/ ti_record.
      endloop.
    else.
      data: TXT_FILE4 TYPE STRING .
      split File AT '.java' into: st1 st2  .
      concatenate st1 'output.txt' into TXT_FILE4.
**************FM GUI_UPLOAD
      CALL FUNCTION 'GUI_UPLOAD'
        EXPORTING
          FILENAME = TXT_FILE4
        TABLES
          DATA_TAB = ti_recORD[].
**********End FM GUI_UPLOAD
      loop at ti_record.
        write:/ ti_record.
      endloop.
    endif.
  endif.
************************end of 
output****************************************

In ZJAVACREATE we have used the transaction new which is nothing but 
the transaction code for zjavamodify.

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