How to read properties file from Jenkins 2.0 pipeline script

I just fought with this yesterday and today. I wish the availability of this was easier to find.

Grab the 'Pipeline Utility Steps' plugin.

Use the readProperties step.

 def props = readProperties  file: 'dir/my.properties'

One word of warning - what I expected to be booleans in the properties files were treated as strings.

I tried out and below works perfectly fine:

test.properties
Monday=abcdef
Tuesday=kfgh

def props = readProperties  file:'/var/lib/jenkins/jobs/abc/test.properties'
def Var1= props['Monday']
def Var2= props['Tuesday']
echo "Var1=${Var1}"
echo "Var2=${Var2}"