Getting error in while controller expression in Jmeter -

i getting exception in while controller using jmeter-maven-plugin.

expression:

${__javascript("${type}" != "reports" && ${counter} < 300;)} 

error -

jmeter.functions.javascript: error processing javascript: ["${type}" != "reports" && ${counter} < 100;]  org.mozilla.javascript.evaluatorexception: missing ; before statement (<cmd>#1 

there nothing wrong while controller expression.

given see ${type} , ${counter} in log instead of real values type , counter variables not set double check way you're setting variables , verify values using debug sampler , view results tree listener combination.

see how debug apache jmeter script article more information on jmeter tests troubleshooting.