Developing codeunits

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Steps for creating a new codeunit

  1. Create a new Java project in your favorite IDE
  2. Import the p2eShared.jar in the project
  3. Create a new class:
    1. The abstract parts are found in: dk.p2e.blanket.codeunit
    2. Implement all abstract methods
    3. Code the method bodies (normally "execute")
  4. Compile and build
  5. Deploy to webservser: [Application]\WEB-INF\lib

After first test of the codeunit a server reboot is needed for each redeployment, as there is no way of removing the loaded classes from memory.

Error handling

Exceptions are handled by themselves using the errorRegistration(Exception e) method.

In case the errors are not caught by the codeunit itself, the generic error handler takes over

  1. Logs the error in the eventlog
  2. Returns a standard error page to the user

Other debugging options include log4j and specialized TempusServa Systemout.print functions (yes, the class name is "Systemout").

 Systemout.println( "hello world" );
 Systemout.printSql( myStatment );

Configuration / parameters

Parameters are delivered through the method call, packed in a nice <String> Hashtable for easy access.

Please note that values are sent as-is, so make sure to escape values before DB operations using

 DbConnection.escapeSql(String s); 

Configurations can be stored using the getConfiguration methods of the command object. These values can be editedthrough the designer, depending on the Codeunit type

  • System configurations: Designer > Modules > Static content
  • Solution configurations: Designer > [Solution] > Advanced > Configurations

Value names will be prefixed with Class simple name - example + "."

 dk.tempusserva.MyExampleCodeunit.myParameter

Variables

Variables can have a scope of either

  • Request
  • User session
  • Application

For permanent variables user server configurations.

Request variables

Request scope variables should be stored in the Hashtable sharedObjects in the Command object.

Note that the HTTP request parameters are stored in requestParameters.

User session variables

Acces the sessionValues attribute in the Security object

  • boolean hasSessionValue(String name)
  • void setSessionValue(String name, boolean value)
  • int getSessionInteger(String name, int defaultValue)
  • int getSessionInteger(String name)
  • void setSessionInteger(String name, int value)
  • String getSessionString(String name, String defaultValue)
  • String getSessionString(String name)
  • void setSessionString(String name, String value)

All variables her are serilizable and will survive server restarts.

Certain special user properties can also be accessed from the Security object

  • boolean hasProperty(String name)
  • String getProperty(String name)

Finally it is possible to store objects in the Hashtable sessionObjects in the Security object, but be aware that data are transient and will not survive server restarts.

Application variables

Application variables are persistent and accessed through the Command object

Their storage position depends on wether theres is a solution context or not:

  • Solution present: Variables are saved to the solution Configurations
  • None (SagID = 0): Variables are saved to the Static content

Access the the variables goes through get methods with default values.

  • String getConfigurationValue(String name)
  • String getConfigurationValue(String name, String defaultValue)

If the variable does not exist it will be created, and set to the default value (if present).

Note that it is possible to force the use of Statis content by explicitly calling

  • String getSystemConfigurationValue(String name)
  • String getSystemConfigurationValue(String name, String defaultValue)

Different codeunit types

Please read the: Codeunit reference

Most likely you will need to create a Codeunit/Formevents that will allow specific changes for a solution, during views, updates or exports.

Most interactions wil require interaction with the following objects

  • Security
  • Command
  • DbConnection
  • EventHandler