Ho to set a new context path for webapp in Eclipse Kepler

Right click on project, then:
->Properties->Web Project Settings->Context root:

If you are building war for glassfish through maven (mvn package), you may create file glassfish-web.xml in the same folder as web.xml and write down:
<!DOCTYPE glassfish-web-app PUBLIC "-//GlassFish.org//DTD GlassFish Application Server 3.1 Servlet 3.0//EN" "http://glassfish.org/dtds/glassfish-web-app_3_0-1.dtd">
<glassfish-web-app error-url="">
<!-- Doesn't work when build with Eclipse -->
    <context-root>/YourContextPath</context-root>
</glassfish-web-app>