English
资源说明：A good basis for spring framework projects running on top of tomcat. Uses simple configuration to highlight many of the features one would expect from a Java Application Server.
fallback
========
# This project is very old now. If you want something more modern and actively maintained, I suggest you look at [GWizard](https://github.com/gwizard/gwizard) instead.
fallback provides a nice example web application archive (war) for
integrating Spring / Hibernate / JMX / JPA / Ehcache.
In order to come up with this clean of an integration, there is a ton of
conflicting blog postings and documentation you would have to sift
through. My goal here is to do that work for you and provide a nice
basis for starting from. The project is up on github in the hopes that
you will fork it and make improvements yourself.
The fallback project itself is a very basic 3-tier web application with
a RESTful servlet frontend that takes a request and calls a method on an
`@Inject`ed bean which contains the business logic. If you are coming from
EJB3 experience, this will look very familiar. Annotations are used as
much as possible to simplify the Spring configuration.
fallback will work with any modern servlet engine that supports api >=
2.5. By default, it is setup to work most easily with Tomcat 6/7, but
you can easily target the build script to point at your favorite
container.
Part of the beauty of this is that this fully functional system is up
and running on Tomcat in about 3 seconds on my laptop.
Database Access
---------------
By example, access to the database is managed through the standard
DAO/Entity pattern. There is also an example of how to use an
EntityManager if you want to go that route instead. The `BaseDAO`
implementation enables hibernate query caching with Ehcache. Adding
`@Cache` to an entity enables fast lookups of objects.
Basic transactions, `set autocommit=0; do work(); set autocommit=1` are
also fully supported in the business logic bean by adding an
`@Transactional` annotation. If an exception is thrown, the final
autocommit isn't executed. Enabling JTA is possible, but out of the
scope of this project.
JMX
---
For JMX, the `JmxAgent` class registers both Ehcache and Hibernate with
the `MBeanServer` that is setup through Spring. Using the
`@ManagedResource` `@ManagedOperation` and `@ManagedAttribute`
annotations on a bean automatically exposes classes, methods and
properties via JMX. No need for over expressive XML configuration for
your beans. There is a logging manager class which allows you to set
logging to debug or info with the click of a button in jconsole.
Build System
------------
The build system for this project doesn't use Maven. Instead we use a
more simple solution called
[Sweetened](http://sweetened.googlecode.com), which is based on top of
Ant. All of the jars that the project needs are located in the lib
directory. This ensures that over time the project can be built
regardless of the state of it. Sweetened is also responsible for
building the Eclipse .classpath and .project files.
There you have it. Please poke around the code and if you have questions
feel free to ask me.
Getting Started
---------------
1. Clone this project: git clone
2. Install tomcat6 somewhere (you can use any modern servlet engine)
3. cd fallback; echo "engine.home=/path/to/tomcat6_or_7" > user.properties
4. ant .eclipse
The .eclipse target will generate a .project and .classpath file
for you so that you can load it easily into Eclipse.
1. Right click in the Project Explorer
2. Import...
3. Import existing project into workspace
4. Select the fallback directory.
5. Go
Now build the project:
ant all
This will copy an exploded war directory into your tomcat6 webapps
directory.
### MySQL
Before you can start up Tomcat, you need a MySQL database called
'fallback' and accessible on localhost by user root with no password.
mysqladmin -u root create fallback
If you want to change any of this before you start up Tomcat, just edit
the database connection settings in the `web/WEB-INF/applicationContext.xml`
file. Integrating with Spring's `PropertyOverrideConfigurer` bean makes
'environment' based settings easy.
The `persistence.xml` file is configured to auto create the table and
all of the columns.
本源码包内暂不包含可直接显示的源代码文件，请下载源码包。
