Error: Could not find or load main class error in Spring Boot project

Question

When I clicked on Run As -> Spring Boot Application Error: Could not find or load main class com.denisa.springframework.springwebapp.SpringwebappApplication message exist.What have done so far:

• Project -> Clean

• Maven - > Update project

• Adding the lines given below to pom.xml:

<properties>
  <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
  <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
  <java.version>1.8</java.version>
  <start-class>com.denisa.springframework.springwebapp.SpringwebappApplication</start-class>
  <maven.compiler.source>1.8</maven.compiler.source>
  <maven.compiler.target>1.8</maven.compiler.target>
</properties>