Add Web Projects from Eclipse to Tomcat

I have a Java projects workspace, with several pure Java projects and several Web J2EE projects.

When import the existing projects into the workspace.  Eclipse can not identify it as a web project, so it can not be added into the tomcat runtime.

After some googling, the solution is as below:
  1. configure the web project's project facet in the properties menu.
     A. First choose 'Dynamic Web Module', please pay attention to the version of the Dynamic Web Module at the end of the check box line.
          The error message tells us that 'Dynamic Web Module 3.0 need Java 6.
     B. Check Java too and change the version of Java to 1.6.
2. Apply and OK.

Install erlang in CentOS 6

 In order to learn more about concurrent programming language, I decide to learn erlang programming in the Linux platform.

Here are the install procedures:
   1. Download the source for linux from :
  2.  Follow the INSTALL.md file in the source package, install available packages.
  3. for the wxWidgets, yum install wxGTK works.  even without wxWidgets, the erlang source can be build and installed.
  4. for openssl, both openSSL and openssl-devel should be installed
  5. some of the devel package should be installed.
  6. build the erlang by reference the INSTALL.md file.