Concept: MVEL and Studio
In Workday Studio, MVEL enables you to inspect and manipulate message parts and component
parameters in your assemblies. You can use MVEL to:
- Extract information from a message.
- Format numbers and dates.
- Replace specific characters in a string.
- Retrieve integration attributes or launch parameters.
You should avoid using MVEL to manipulate large strings of data. Example: converting
messages to strings can create performance and scalability issues.
In an MVEL-capable field, you can press Ctrl+Space to display a content assist popup
window.
MVEL expressions can be single statements or multiline scripts. For multiline scripts,
use a semicolon to separate each line.
Studio evaluates multiline expressions as a
unit, not sequentially.
MVEL-capable fields expand to accommodate new lines. After 6 lines, they stop expanding
and become scrollable. Studio applies syntax coloring to MVEL expressions.
MVEL implements operator precedence during execution. You can use brackets to control the
execution order of MVEL expressions.
Because
they're processed in memory, there's a 1 million character limit on XPath methods
such as
xpath
, xpathB
, and
xpathF
. You will not receive an error if your query exceeds this
limit. You should use streaming APIs such as the write
step's
xml-stream
element if you need to process large
messages.