Purpose

Here is a Java Bean that allows to get some client machine information.






The Java code

     ClientInfos.java



The implementation class of the Bean Item

     oracle.forms.fd.ClientInfos

The methods you can get



Get all client information

Get_Custom_Property('BLOCK.ITEM',1,'GET_CLIENT_INFOS');

e.g.:
-- get all information --
:BL.INFOS := Get_Custom_Property('BL.BEAN', 1, 'GET_CLIENT_INFOS' ) ; 

Get a particular client information

Get_Custom_Property('BLOCK.ITEM',1,'property');

where property could be one of the following:

OPERATING : Operating System
ARCHITECTURE : architecture
OSVERSION : OS version
IP : IP address
MAC : MAC address
JAVAVERSION : Java version
JAVAVENDOR : Java vendor
JAVAVENDORURL : Java vendor URL
JAVAHOME : Java vendor home page
JAVAVMSPECIFICATIONVERSION : Virtual machine version
JAVAVMSPECIFICATIONVENDOR : Virtual machine vendor
JAVAVMSPECIFICATIONNAME : Virtual machine name
USERNAME : user name
USERHOME : user home

e.g.:
-- get MAC address --
:BL.INFOS := Get_Custom_Property('BL.BEAN', 1, 'MAC' ) ; 

Purpose

Here is a Java Bean that allows reading, displaying with scaling and writing images.

It allows scaling images to fit the target item size, and includes a FileChooser with image preview dialog.

In its third version, it does not need any JDBC connexion to handle images from/to the database.

It uses the JRE 1.4 javax.imageio.ImageIO package, so it needs, at least the Sun Java plugin 1.4.
It won't run against JInitiator.






The Java code

     handleimage3.java      GetImageFileName.java



The implementation class of the Bean Item

     oracle.forms.fd.HandleImage


The methods you can call




Read an image from a file

Set_Custom_Property('BLOCK.ITEM',1,'READIMGFILE','the_complete_filename');

e.g.:
-- read image from the file system --
Set_Custom_Property( 'BLZ.BEAN', 1, 'READIMGFILE', 'D:/image.jpg' ) ; 

-- read image from the JAR file --
Set_Custom_Property( 'BLZ.BEAN', 1, 'READIMGFILE', '/image.jpg' ) ;

-- read image from the Internet --
Set_Custom_Property( 'BLZ.BEAN', 1, 'READIMGFILE', 'http://the_url/image.jpg' ) ;

Read an image from the database table

The reading process is composed by three steps:

1. Select the Blob table's column
2. Read the image chunks and send them to the Java Bean
3. End the sending process

1. Select the Blob table's column:

Pkg_Read_Blob_Image.Select_Blob(LC$Clause); (*)

LC$Clause is a string that must contain the Select order to fetch the corresponding single row:

 LC$Clause := 'Select PHOTO_JAVA From PHOTOS Where IDENTIFIANT = 10'  ;
 -- Select the Blob column --
 If Pkg_Read_Blob_Image.Select_Blob(LC$Clause) Then
    ...

2. Read the image chunks from the database then send them to the Java Bean:

Pkg_Read_Blob_Image.Get_B64_Chunk() (*)

     -- Get the image chunks from the database --
     LC$Image := Pkg_Read_Blob_Image.Get_B64_Chunk ;
     If LC$Image Is Not Null Then
       -- Send the chunks to the Java Bean --
       Set_Custom_Property( 'BLZ.BEAN', 1, 'READIMGBASE', LC$Image ) ;

3. End the sending process:

     Else
       -- End the sending process --
       Set_Custom_Property( 'BLZ.BEAN', 1, 'READIMGBASE', '[END_IMAGE]' ) ;

(*) the PKG_READ_BLOB_IMAGE database's package is provided with the zip file.

1. Initialize the transfer
2. Read the image chunks from the Java Bean and send them to the database
3. Update the Blob column with the new content

1. Initialize the transfer:

Pkg_Read_Blob_Image.Init_Transfer() (*)

This will empty the current Blob column:

 Pkg_Read_Blob_Image.Init_Transfer ;

2. Read the image chunks from the Java Bean and send them to the database:

Get_Custom_Property('BLZ.BEAN',1,'GETIMAGE');

Pkg_Read_Blob_Image.Set_B64_Chunk(LC$Req) (*)

    Loop
      -- Get the image chunk from the Java Bean --
      LC$Req := Get_Custom_Property('BLZ.BEAN',1,'GETIMAGE');
      Exit When LC$Req is null ;
      ...   
      -- Send the image chunks to the Database --
      Pkg_Read_Blob_Image.Set_B64_Chunk(LC$Req);
    End loop;

3. Update the Blob column with the new content:

     LC$Res := Pkg_Read_Blob_Image.Save_Blob('PHOTOS','PHOTO_JAVA','IDENTIFIANT=' || :PHOTOS.IDENTIFIANT );

The Save_Blob() function takes the table name, the blob column name and the Where clause arguments.

(*) the PKG_READ_BLOB_IMAGE database's package is provided with the zip file.

Any value greater then 0 that express an absolute size in pixels
the special value: FIT that extends the image to fit the exact size of the image panel' size
-1 that to keep the corresponding aspect ratio
0 that indicates no scale at all

Examples:

-- Scale the image to fit horizontally and vertically the image item --
Set_Custom_Property('BLZ.BEAN',1,'SCALE_IMAGE', 'Width=FIT,Height=FIT' ) ;

-- Scale the image to 200x100 pixels --
Set_Custom_Property('BLZ.BEAN',1,'SCALE_IMAGE', 'Width=200,Height=100' ) ;

-- Scale the image to 200 horizontal pixels and keep vertical aspect ratio --
Set_Custom_Property('BLZ.BEAN',1,'SCALE_IMAGE', 'Width=200,Height=-1' ) ;




Display/hide the image panel' scrollbars

Set_Custom_Property('BLOCK.ITEM',1,'SETSCROLL','true|false');

e.g.:
Set_Custom_Property( 'BLZ.BEAN', 1, 'SETSCROLL', 'true' ) ; 





Set the item border

Set_Custom_Property('BLOCK.ITEM',1,'SETBORDER','thick[,color]');

e.g.:

-- set a null border --
Set_Custom_Property( 'BLZ.BEAN', 1, 'SETBORDER', '0' ) ; 

-- set a 4 pixel red border --
Set_Custom_Property( 'BLZ.BEAN', 1, 'SETBORDER', '4,r255g0b0' ) ; 



Set the JFileChooser title and starting directory

Set_Custom_Property('BLOCK.ITEM',1,'SET_FILECHOOSER_TITLE','title[,directory]');

e.g.:
Set_Custom_Property( 'BLZ.BEAN', 1, 'SET_FILECHOOSER_TITLE', 'Select a file,D:/' ) ; 

the directory argument is not mandatory



Set the JFileChooser Look and Feel

Set_Custom_Property('BLOCK.ITEM',1,'SET_FILECHOOSER_LAF','SYSTEM|other_value');

e.g.:
-- use the current O.S. L&F --
Set_Custom_Property( 'BLZ.BEAN', 1, 'SET_FILECHOOSER_LAF ', 'SYSTEM' ) ; 

-- use the Metal L&F --
Set_Custom_Property( 'BLZ.BEAN', 1, 'SET_FILECHOOSER_LAF ', 'JAVA' ) ; 


Set the log mode to output the Bean messages

Set_Custom_Property( 'BL.BEAN', 1, 'SETLOG' , 'true|false' ) ;

In the sample dialog provided, here is the code used in the When-New-Form-Instance trigger:

PROCEDURE InitForm IS
BEGIN
  -- switch the log to true --
  Set_Custom_Property( 'BLZ.BEAN', 1, 'SETLOG', 'true' ) ;
  -- set the baen image bckground color --
  Set_Custom_Property( 'BLZ.BEAN', 1, 'SETBG', '255,255,255' ) ;
  -- Set the JFileChooser title --
  Set_Custom_Property( 'BLZ.BEAN', 1, 'SET_FILECHOOSER_TITLE',  'Select an image file' ) ;
  -- Set the JFileChooser L&F --
  Set_Custom_Property( 'BLZ.BEAN', 1, 'SET_FILECHOOSER_LAF', 'SYSTEM' ) ;
  -- scalling properties --
  Set_Custom_Property('BLZ.BEAN',1,'SCALE_IMAGE','Width=FIT,Height=FIT' ) ;
  -- display scrollbars policy --
  Set_Custom_Property( 'BLZ.BEAN', 1, 'SETSCROLL',  'false' ) ;  
END;

Here is the description of the database table used:

CREATE TABLE PHOTOS
   (   
      "IDENTIFIANT" NUMBER(5,0) NOT NULL ENABLE,
      "NOM" VARCHAR2(50 BYTE),
      "PHOTO" BLOB,
      "PHOTO_JAVA" BLOB,
      CONSTRAINT "PHOTO_PK" PRIMARY KEY ("IDENTIFIANT") ENABLE
   )
/



The properties you can get from the JavaBean


Get the image size

Varchar2 := Get_Custom_Property( 'BL.BEAN', 1, 'GETSIZE' ) ;

The format returned (width,height) is like the following : 50,120



Get the selected filename (JFileChooser)

Varchar2 := Get_Custom_Property( 'BL.BEAN', 1, 'GET_FILE_NAME' ) ;

this method both displays the JFileChooser and returns the selected file.

Get the current image chunks

Varchar2 := Get_Custom_Property( 'BL.BEAN', 1, 'GETIMAGE' ) ;

This method returns the last image read by the READIMGFILE() method..
It returns null when the image is completly read.

The sample dialog


     . Download the handleimage3.zip file
     . Unzip the file
     . run the create_table.sql script under the Oracle user you want to test (It creates the sample image table).
     . run the PKG_READ_BLOB_IMAGE.sql script under the Oracle user you want to test (It creates the database package).
     . copy the handleimage3.jar file in the <ORACLE_HOME>/forms/java directory
     . Edit your /forms/server/formsweb.cfg file to add the handleimage3.jar .
     . Open the HANDLEIMAGE3.fmb module (Oracle Forms 9.0.2)
     . Compile all and run the module

Purpose

Here is a Java Bean to handle CLOB/NCLOB database columns in a Forms application.

It needs a database package to read the LOB data from the database, split into chunks in order to send them to Forms and finally to the JavaBean, and also to send back the modified text from the JavaBean to the database LOB column.

This package (PKG_CLOB), provided in the zip file, have functions and procedures to handle both CLOB and NCLOB columns.
It uses the EXECUTE IMMEDIATE function to Read and Write via full SQL orders passed as argument, so it is generic.

It has been successfully tested with Forms 10.1.2 and XE database.







The Java code

     bigtextarea.java

The implementation class of the Bean Item

     oracle.forms.fd.TextArea

The methods you can call


Add text to the text item

Set_Custom_Property('BLOCK.ITEM',1,'ADD_TEXT','text');

e.g. :

LC$Text := 'Text to send to the bean' ;
Set_Custom_Property( 'BL.BEAN', 1, 'ADD_TEXT', LC$Text ) ;   

Use this method to read the database CLOB/NCLOB content then send it to the bean.

Here is a sample code you could write in a Post-Query trigger for instance:

Declare
  LN$Length  pls_integer ;
  LC$Chunk   Varchar2(32767) ;
  LN$Cpt     pls_integer := 0 ;
  LC$Req     Varchar2(1024);
Begin    
 
  ----------------------------------
  --  Build the Select SQL order  --
  ----------------------------------
  LC$Req := 'Select NTEXT From TEST_CLOB Where ID=1' ;
 
  ---------------------------------------
  --  select the database CLOB column  --
  ---------------------------------------
  If pkg_clob.select_nclob(LC$Req) then
    Loop
      -------------------------
      --  get the chunks...  --
      -------------------------
      LC$Chunk := pkg_clob.get_nchunk ;
      Exit when LC$Chunk is null ;
      LN$Cpt := LN$Cpt + 1 ;
      --------------------------------------
      --  ... then send them to the Bean  --
      --------------------------------------
      Set_Custom_Property('BLOCK3.BEAN',1, 'ADD_TEXT',LC$Chunk);
    End loop ;
    ---------------------------------
    --  display the complete text  --
    ---------------------------------
    Set_Custom_Property('BLOCK3.BEAN',1, 'SHOW','');
    ---------------------------
    --  get the text length  --
    ---------------------------
    LN$Length := Get_Custom_Property('BLOCK3.BEAN',1,'GET_LENGTH') ;
    message('length=' || LN$Length);    
  Else
    message('problem reading CLOB');      
  End if ;
 
end;

In this sample, we are selecting  the content of the NTEXT NCLOB column from the TEST_CLOB table.


Display the complete text

Set_Custom_Property('BL.BEAN',1,'SHOW','');

Use this method when all teh text chunks have been sent to the bean.

Clear the text

The properties you can get from the JavaBean


Get the current text length

Varchar2 := Get_Custom_Property( 'BL.BEAN', 1, 'GET_LENGTH' ) ;

Get the current text chunks

Varchar2 := Get_Custom_Property( 'BL.BEAN', 1, 'GET_TEXT' ) ;

Use this method in a loop to get every chunk, then store them in the corresponding CLOB/NCLOB database column.

Here is a sample  code you can use in a Post-Insert or Post-Update trigger:

Declare
    LC$Chunk  Varchar2(32767) ;
    LC$Req    Varchar2(1024) ;
    LC$Msg    Varchar2(4000);
Begin  
    --------------------------------
    --  set the UPDATE SQL order  --
    --------------------------------
    LC$Req := 'Update TEST_CLOB Set NTEXT = :1 Where ID=1' ;
    -------------------------------------
    --  Init the transfer for a NCLOB  --
    -------------------------------------
    PKG_CLOB.Init_Transfer ( 'NCLOB' );
    Loop
      LC$Chunk := Get_Custom_Property('BLOCK3.BEAN',1,'GET_TEXT') ;
      Exit When  LC$Chunk Is Null ;
      ---------------------------------------
      --  Send the chunks to the database  --
      ---------------------------------------
      PKG_CLOB.Set_NChunk ( LC$Chunk ) ;
    End loop;
    ---------------------------------------------
    --  Update the CLOB/NCLOB database column  --
    ---------------------------------------------
    LC$Msg :=  PKG_CLOB.Transfer( LC$Req, 'NCLOB' ) ;
    If LC$Msg = 'OK' Then
     Forms_ddl('Commit') ;
    Else
         Message(LC$Msg);
    End if ;
End;

The writting process is done through three steps:

• init the transfer by cleaning the target CLOB/NCLOB package's variable with Init_Transfer()
• send the chunks to the database package to populate the package CLOB/NCLOB variable with Set_Chunk()
• update the database row with the current CLOB/NCLOB variable with Transfer()

The sample dialog


     . Download the bigtextarea.zip file
     . Unzip the file
     . copy the bigtextarea.jar file in the <ORACLE_HOME>/forms/java directory
     . Edit your /forms/server/formsweb.cfg file to add  bigtextarea.jar .
     . If needed, create the database sample table (create_table_test_clob.sql)
     . create the database package (pkg_clob.sql)
     . Open, compile and run the BIGTEXT.fmb module (Oracle Forms 9.0.2)