Lab Logic Toolkit FAQ

What Java/Groovy methods can I use in a Lab Logic Toolkit (LLTK) Expression?

You can use all methods included in the Java and Groovy base packages.

Commonly used Java classes are:

• String: http://docs.oracle.com/javase/8/docs/api/java/lang/String.html

• Math: https://docs.oracle.com/javase/8/docs/api/java/lang/Math.html

For information on Groovy closures, see .

How do I handle attempts to access custom fields that do not exist or do not have a value set?

Use the hasValue function to check for nonexistent fields and fields that do not have a value set - including toggle switches in LIMS v5 and later.

See .

How do I prevent a user from moving to the next screen if certain criteria are not met?

Use the hasValue function together with the fail() method to check for step UDF / custom field values when the Record Details screen is exited, and prevent the user from advancing to the next screen if they have not entered values for these fields.

See .

How do I control the number of decimal places for a custom field?

Use the following expression:

1. Use Groovy syntax to format the following string:

2. Replace step.::counter:: with the field you want to apply the formatting to.

3. Replace %.0f with the number of decimal places needed. For example, for three decimal places, use %.3f.

Example:

How do I round to the closest integer below a value using Math.floor?

Use the following expression:

How do I use LLTK with required custom fields?

Custom fields are set as a bulk group in the API. The API checks all required fields.

When LLTK updates a field, all required fields must be set or an error will occur.

Workaround:

1. Set the required fields with a value such "Please fill in this value".

2. Use another LLTK expression triggered on step completion to check whether this value has been updated.

   • If the field value has been updated, allow the step to proceed.