custom ON-ERROR And ON-MESSAGE On Oracle forms

At Forms Level 
create tow Trigger

1-ON-ERROR 

declare
     errnum number := ERROR_CODE;
     errtxt varchar2(80) := ERROR_TEXT;
     errtype varchar2(3) := ERROR_TYPE;
     field_name varchar2(30);
begin

     field_name := substr(:SYSTEM.TRIGGER_ITEM ,instr(:SYSTEM.TRIGGER_ITEM ,'.') + 1);
     message( 'ERROR ' || field_name || ': ' ||errtxt); message( 'ERROR ' || field_name || ': ' ||errtxt);
     display_error;
     raise form_trigger_failure;
     end;

2-ON-MESSAGE

DECLARE
  lv_errtype VARCHAR2(3)  := MESSAGE_TYPE;
  lv_errcod NUMBER        := MESSAGE_CODE;
  lv_errtxt VARCHAR2(80)  := MESSAGE_TEXT;
BEGIN
  IF lv_errcod = 40400 THEN
     Message('saved Successfully'); Message('saved Successfully');
 -- ELSIf lv_errcod in(42100) Then
    --null;
 ELSIF lv_errcod IN( 42100 ) AND lv_errtype='FRM' THEN
  NULL;
 ELSE
 
    Message(lv_errtype||'-'||to_char(lv_errcod)||':  '||lv_errtxt);
    Message(lv_errtype||'-'||to_char(lv_errcod)||':  '||lv_errtxt);
  END IF;
END; 

sign oracle forms jar file

to enable security for jar file we need to sign it using the following step

1.    using dos command do the following : cmd> keytool -genkey -alias keystore01 -keyalg RSA -keystore mypassword

where C:\Oracle\midtierhome is the oracle home 

Enter keystore password:  mypassword

What is your first and last name?

  [Unknown]:  Joe Bloggs

What is the name of your organizational unit?

  [Unknown]:  My Department

What is the name of your organization?

  [Unknown]:  My Company

What is the name of your City or Locality?

  [Unknown]:  My City

What is the name of your State or Province?

  [Unknown]:  My State

What is the two-letter country code for this unit?

  [Unknown]:  UK

Is CN=Joe Bloggs, OU=My Department, O=My Company, L=My City, ST=My State, C=UK correct?

  [no]:  yes

Enter key password for <myapp>

        (RETURN if same as keystore password):

2.    then use the keystore to sign the jar file by using command line run this:

C:\Oracle\midtierhome\jdk\bin\jarsigner -keystore keystore01  -storepass mypassword C:\Oracle\midtierhome\forms\java\hl_icons.jar keystore01