May be someone did this:
I have alfreso, share and myWebApp on same tomcat(alfresco_tomcat). Then, I uncomment: "<.Valve className="org.apache.catalina.authenticator.SingleSignOn" />" in $Alfresco_tomcat/conf/server.xml.
What are my next steps should be to get the current user in myWebApp. I have enough simply login, which was authorized in Alfresco (or Share).
Please, help me.