SOAP UI Problems to remove custom property - groovy

Question

I'm currently trying to 'clean up' custom properties from a SOAP UI test case, using groovy script.
From this other post, I tried to do so but I'm facing a problem : I can't access the removeProperty method.
I get my data :
data = context.testCase.testSuite.getTestCaseByName("Test multi TT");
and from it I can only use a removePropertyChangeListener method.
I tried to use data.getPropertyAt() function to get a suitable object but it does not return the correct data class.
How can I get a PropertyChangeListener parameter from my custom property that I could use to remove it programmatically ?
All the posts I've been through provide answers with removeProperty and I can't find any that mentions removePropertyChangeListener
any help appreciated
EDIT: Based on the discussion over chat with OP, OP wants to remove the existing properties and add properties from external file to test case level custom properties.

Answer 1

Below is the Setup Script for the soapui test case. And this does the following (after discussion with OP on the chat):
Remove existing properties
Add the properties from file to test case level custom properties.
Setup Script:
//Change external properties file path as needed
def filename = 'C:/Users/apps/Documents/test.properties'
def properties = new Properties()
def propertiesFile = new File(flename)
assert propertiesFile.exists(), "$filename does not exists"
propertiesFile.withInputStream { properties.load(it) }
//Remove properties
testCase.propertyNames.collect { testCase.removeProperty(it) }
//load the properties of external file
properties.collect { k, v -> testCase.setPropertyValue(k, v) }

Answer 2

Here is a solution with no external file. The aim is to remove only the new properties I created for testCase purpose, in the teardown script:
import java.util.regex.Pattern
data = context.testCase.testSuite.getTestCaseByName("myTestCase");
log.info " ********************** old props ***********************"
String[] customProps = new String[data.getPropertyCount()];
customProps = data.getPropertyNames();
Pattern myRegex = ~/maProp_/ // I name my new properties with the same pattern and an index
for (propertyName in customProps){
log.info "info = " + propertyName
myMatcher = propertyName =~ /$myRegex/
if (myMatcher.count != 0){
match = myMatcher[0] == 'maProp_'
//log.info "match ? " + match // to check only my maProp_xx properties are matching
context.getTestCase().removeProperty(propertyName)
}
}
// verification
newProps = data.getPropertyNames();
log.info " ********************** new props ***********************"
for (i in newProps){
log.info "info = " +i
}