The Liberty profile is
a highly composable, fast-to-start, dynamic application server runtime
environment.
You install the Liberty profile when you install WebSphere® eXtreme Scale with WebSphere Application Server Version 8.5.
Because the Liberty profile does not include a Java™ runtime environment (JRE), you have to
install a JRE provided by either Oracle or IBM®.
For more information
about supported Java environments
and locations, see Minimum supported Java levels in the WebSphere Application Server Information
Center.
This server supports two models of application deployment:
- Deploy an application by dropping it into the dropins directory.
- Deploy an application by adding it to the server configuration.
The Liberty profile supports a subset of the following
parts of the full WebSphere Application Server programming model:
- Web applications
- OSGi applications
- Java Persistence API (JPA)
Associated services such as transactions and security are
only supported as far as is required by these application types and
by JPA.
Features are the units of capability by which you
control the pieces of the runtime environment that are loaded into
a particular server. The Liberty profile includes the following main
features:
- Bean validation
- Blueprint
- Java API for RESTful Web
Services
- Java Database Connectivity
(JDBC)
- Java Naming and Directory
Interface
- Java Persistence API (JPA)
- JavaServer Faces (JSF)
- JavaServer Pages (JSP)
- Lightweight Directory Access Protocol (LDAP)
- Local connector (for Java Management Extensions (JMX) clients)
- Monitoring
- OSGi JPA (JPA support for OSGi applications)
- Remote connector (for JMX clients)
- Secure Sockets Layer (SSL)
- Security
- Servlet
- Session persistence
- Transaction
- Web application bundle (WAB)
- z/OS® security
- z/OS transaction management
z/OS workload
management
You can work with the runtime environment directly, or
using the WebSphere Application
Server Developer Tools for Eclipse.
On distributed platforms,
the Liberty profile provides both a development and an operations
environment. On the Mac, it provides a development environment.
On z/OS systems, the Liberty profile provides an operations environment.
You can work natively with this environment using the MVS™ console. For application development, consider
using the Eclipse-based developer tools on a separate distributed
system, on Mac OS, or in a Linux shell on z/OS.
Running the Liberty profile with a third-party JRE
When you use a JRE that Oracle provides, special considerations must
be taken to run
WebSphere eXtreme Scale with the Liberty profile.
- Classloader deadlock
- You might experience a classloader deadlock which has been worked
around using the following JVM_ARGS settings. If you experience a
deadlock in BundleLoader logic, add the following arguments:
export JVM_ARGS="$JVM_ARGS -XX:+UnlockDiagnosticVMOptions -XX:+UnsyncloadClass"