Java extension: write log messages

You can read this log by using ServiceCenter or selecting directly from the database table (OSLOG_GENERAL), if you have the proper database privileges of course.

To write messages to OutSystems “General” log, you can use the following (static) methods:

• GenericExtendedActioins.audit
• GeneralLog.staticWrite

The “audit” method is the simplest of them, while it only requires 3 arguments to be specified:

1. The OutSystems application context
2. The message you want to write to the log (maximum of 2000 characters)
3. A “module” name that you can use to filter on in ServiceCenter (maximum of 15 characters)

A simple example of using the static “audit” method, that will write the message “Write my message” to the general log table, using “MyModule” as the module name, is:

GenericExtendedActions.audit(AppInfo.getAppInfo().getOsContext(), “Write my message”, “MyModule”);

The “staticWrite” method of the GeneralLog class requires more arguments to be specified, but gives you more control over the various fields stored in the log table. You can, as an example, specify a specific timestamp.

The parameters that are defined by the “staticWrite” method are:

1. Timestamp
2. Session ID (String value)
3. eSpace ID
4. Tenant ID
5. User ID
6. Message you want to write to the log (maximum length 2000 characters)
7. Message type (normally USER, INFO, WARNING – maximum length 10 characters)
8. A “module” name that you can use to filter on in ServiceCenter (maximum of 15 characters)
9. Error Identifier. A String value you can specify to add extra information. You won’t however see the content of this field, when using ServiceCenter (maximum of 50 characters)

Here’s an example of using the GeneralLog.staticWrite method, writing the message “Message to write” to the general log table, using “MyModule” as the module name that you might use to filter on in ServiceCenter:

GeneralLog.staticWrite(DateTime.getNow(), AppInfo.getAppInfo().getOsContext().getSession().getSessionID(), AppInfo.getAppInfo().geteSpaceId() , AppInfo.getAppInfo().getTenant().getId(), AppInfo.getAppInfo().getOsContext().getSession().getUserId(), “Message to write”, “USER”, “MyModule”, ” “);

Besides these methods you can use to write to OutSystems “General” log, there’s also an option to write to OutSystems “Error” log (database table OSLOG_ERROR). For this you should use the ErrorLog class, that contains various methods for this purpose.

Here’s an example to write a message to the “Error” log:

ErrorLog.staticWrite(DateTime.getNow(), AppInfo.getAppInfo().getOsContext().getSession().getSessionID(), AppInfo.getAppInfo().geteSpaceId() , AppInfo.getAppInfo().getTenant().getId(), AppInfo.getAppInfo().getOsContext().getSession().getUserId(), “Message to write”, “Error stack”, “Env. info”, “MyModule”);