Group items tagged

highly type-safe

consistent

portable

CDI enhances the Java EE programming model in two more important ways

allows you to use EJBs directly as JSF backing beans

CDI allows you to manage the scope, state, life-cycle and context for objects in a much more declarative fashion, rather than the programmatic way

CDI has no component model of its own

set of services that are consumed by Java EE components such as managed beans, Servlets and EJBs.

well-defined create/destroy life-cycle that you can get callbacks for via the @PostConstruct and @PreDestroy annotations.

Managed beans

annotation

CDI also integrates with JSF via EL bean name resolution

CDI does not directly support business component services such as transactions, security, remoting, messaging

JSR 330 defines a minimalistic API for dependency injection solutions and is primarily geared towards non-Java EE environments.

Figure 1 shows how CDI fits with the major APIs in the Java EE platform.

none of this uses string names that can be mistyped and all the code is in Java and so is checked at compile time

are additional pieces of meta-data that narrow down a particular class when more than one candidate for injection exists

can be handled on the

by defining a

possible to define common handlers for particular fault codes on the client-side, and exception converters on the server-side, to convert server exceptions to common fault codes

define an

class

Converter

ExceptionConverter

t.getMessage(), detail, t

ENTITY_NOT_FOUND

This class will

all EntityNotFound exceptions on the server-side, and convert it to a proper ENTITY_NOT_FOUND fault event.

exception converter has to be

scan="true" in granite-config.xml

in the jar containing the exception converter class

granite-config.xml

<exception-converters> <exception-converter type="com.package.SomeExceptionConverter"/> </exception-converters>

Handler

register it as an exception handler for the

in a static initializer block to be sure it is

ExceptionConverter

5. Exception Handling

5. Exception Handling

describing its parameter object and is therefore not type-safe and its use is subject to many syntax errors.

GraniteDS provides a Java-like reflection API that encapsulates describeType calls and offers a type-safe, object-oriented, set of reflection classes and methods

caches its results for better performance

supports advanced features such as ApplicationDomain and namespaces

There is a drawback: not all views are updatable. Whether a view is updatable or not highly depends on the complexity and particular database

for each workspace, in files stored in <workspace>/.metadata/.plugin/org.eclipse.core.runtime/.settings

for each project --for project-level settings -- in files stored in a .settings sub-directory of your project folder

Is there an UML editor for Eclipse? An Eclipse Modelling project-based UML editor can be installed from the Eclipse update site "Modelling > UML2 Tools SDK". See Creating UML 2 diagrams with Eclipse UML2 Tools - Tutorial for an introduction.

How do I debug Eclipse? How can I see what plug-ins are being started? Why aren't the plug-ins I installed showing up in the UI? How do I start the OSGi console?

Debugging OSGi Bundle Loading Issues There are a few flags you can pass to Eclipse on the commandline or in your eclipse.ini file that might help: -consolelog - log everything in workspace/.metadata/.log to the console where you launched Eclipse as well -debug - more verbose console output -console - start the Equinox OSGi console to interact with OSGi directly -noexit - when Eclipse closes, keep the OSGi console running until you type 'exit' or hit CTRL-C so you can keep debugging See Where Is My Bundle? for an overview of how to use the OSGi console for diagnosing problems.

Debugging Eclipse Using Eclipse You can also debug an Eclipse instance from another instance through remote debugging: Start the instance to be debugged with "-vmargs -Xdebug -agentlib:jdwp=transport=dt_socket,server=y,address=8000". You should see a message like "Listening for transport dt_socket at address: 8000" Open Run → Debug Configurations... and create a Remote Java Application configuration with connection type "Socket Attach" and connecting to the client at port 8000. Set the project to a bundle project with the right dependencies for the bundles that you are trying to debug. Launch the configuration. The JDWP agent supports other useful arguments, like "suspend=n" so that the process does not suspend. For more details, see Oracle's Java Debug Wire Protocol (JDWP) connection docs.

I just installed Eclipse on my 64-bit system, but it does not start. What is the problem? Make sure that you have downloaded the 64-bit version of Eclipse (it should have x86_64 somewhere in its name) and have installed a 64-bit JVM. Likewise, if you run a 32-bit JVM, then you should use the 32-bit version of Eclipse.

When I start Eclipse it says "Workspace in use or cannot be created, choose a different one.", what should I do? There are a couple of things you can try. Delete the workspace/.metadata/.lock file. Check your running processes to make sure there aren't any remaining Java or Eclipse processes running. When in doubt, restart your computer. :) Try starting Eclipse on a different workspace (from the workspace selection dialog, or by using a command line argument like -data /home/user/tmp-workspace), then switch back to your original workspace.

How do I uninstall a plug-in? You can view your list of installed software by checking your installation details from about dialog. Help > About > Installation Details

I'm having memory, heap, or permgen problems, what can I do? FAQ How do I increase the heap size available to Eclipse? FAQ How do I increase the permgen size available to Eclipse?

Eclipse seems to be hanging on startup. How can I find out why? If none of the solutions outlined in this section reveal the problem, then you can try debugging an Eclipse instance as a debug target from another Eclipse instance. This is surprisingly easy: Start Eclipse in a "new" blank workspace (e.g., C:\TEMP\WS, or /tmp) Create a new Debug configuration: Run -> Debug Configurations; then click on "Eclipse Applications" and select the New Launch Configuration. If you believe it's something about a particular workspace, then set the workspace to your normal workspace. If you believe the hang is caused by a particular plugin, disable the plugin and verify. Launch and then see. Using this approach, you can break with the debugger to see where hangs are occurring. You can also change the selection of plugins that the instance is launched with.

I was working on a project and doing something or other does not work. Where should I start? Try refreshing your projects. Try cleaning your your projects using the menu item Project/Clean to trigger a rebuild. Try closing/reopening your projects. Try restarting Eclipse.

4.2 Where are Eclipse's log files located?

Where are Eclipse's log files located? <workspace>/.metadata/.log You can view this workspace log as a view if you have PDE installed on your computer (which you would if you have downloaded the Eclipse SDK). You can open that view via Window -> Show View -> Other -> PDE Runtime -> Error Log. <eclipse install>/configuration/<sometimestamp>.log <eclipse install>/configuration/org.eclipse.update/install.log

Where are Eclipse preferences stored?

Where are Eclipse preferences stored?

Where are Eclipse preferences stored?

Where are update site bookmarks stored? It is within an XML file called <user_home>/.eclipse/org.eclipse.platform_3.1.2/configuration/org.eclipse.update/bookmarks.xml. Your Eclipse version may vary.

Built-in Salt and repeated hashing support

a) stop writing dynamic queries

b) prevent user supplied input which contains malicious SQL from affecting the logic of the executed query

Primary Defenses:

Option #1: Use of Prepared Statements (Parameterized Queries)

Option #3: Escaping all User Supplied Input

Additional Defenses:

Perform: White List Input Validation

Primary Defenses

Defense Option 1: Prepared Statements (Parameterized Queries)

attacker is not able to

of a query, even if SQL commands are inserted by an attacker

allows the database to

distinguish

between

Defense Option 3: Escaping All User Supplied Input

GraniteDS validation framework provides a set of standard constraints

Constraint Description AssertFalse The annotated element must be false AssertTrue The annotated element must be true DecimalMax The annotated element must be a number whose value must be lower or equal to the specified maximum DecimalMin The annotated element must be a number whose value must be greater or equal to the specified minimum Digits The annotated element must be a number whithin accepted range Future The annotated element must be a date in the future Max The annotated element must be a number whose value must be lower or equal to the specified maximum Min The annotated element must be a number whose value must be greater or equal to the specified minimum NotNull The annotated element must not be null Null The annotated element must be null Past The annotated element must be a date in the past Pattern The annotated String must match the supplied regular expression Size The annotated element size must be between the specified boundaries (included)

must use

Note that the bundle name must always be set to "ValidationMessages".

Extract/replace AMF data during the test in order to variabilize the calls

Automatically handle the session IDs used by AMF

how to perform integration tests of you Java EE 6 application using Arquillian

The discussion whether or not to use Spring vs. Java EE for new enterprise Java applications is a no-brainer

Why migrate?

since then fallen a prey to the hungry minds of Venture Capitalists and finally into the hands of a virtualization company called VMware

While the different companies and individuals behind the Spring framework have been doing some work in the JCP their voting behavior on important JSRs is peculiar to say the least

outdated ORM solution like JDBC templates

some developers completely stopped looking at new developments in the Java EE space and might have lost track of the current state of technology

size of the deployment archive

fairly standard Java EE 6 application will take up about 100 kilobytes

comparable Spring application weighs in at a whopping 30 Megabytes!

Lightweight

Firing up the latest JBoss AS 7 Application Server from scratch and deploying a full blown Java EE 6 application into the server takes somewhere between two and five seconds on a standard machine. This is in the same league as a Tomcat / Spring combo

Dependency injection

Java EE 6, the Context and Dependency Injection (CDI) specification was introduced to the Java platform, which has a very powerful contextual DI model adding extensibility of injectable enterprise services

Aspect Oriented Programming

“AOP Light” and this is exactly what Java EE Interceptors do

common pitfall when taking AOP too far is that your code might end up all asymmetric and unreadable. This is due to the fact that the aspect and its implementation are not in the same place. Determining what a piece of code will do at runtime at a glance will be really hard

Testing

With Arquillian we can get rid of mocking frameworks and test Java EE components in their natural environment

Tooling

capabilities comparison matrix below to map Spring’s technology to that of Java EE

Capability Spring JavaEE Dependency Injection Spring Container CDI Transactions AOP / annotations EJB Web framework Spring Web MVC JSF AOP AspectJ (limited to Spring beans) Interceptors Messaging JMS JMS / CDI Data Access JDBC templates / other ORM / JPA JPA RESTful Web Services Spring Web MVC (3.0) JAX-RS Integration testing Spring Test framework Arquillian *

3 separate projects: a Java project, a Flex project and a Webapp project.

GraniteDS archetypes

archetypeGroupId: org.graniteds.archetypes archetypeVersion: 1.1.0.GA archetypeArtifactId:

Maven 3.x required

mvn archetype:generate    -DarchetypeGroupId=org.graniteds.archetypes    -DarchetypeArtifactId=graniteds-tide-spring-jpa-hibernate    -DarchetypeVersion=1.1.0.GA    -DgroupId=org.example    -DartifactId=springgds    -Dversion=1.0-SNAPSHOT

cd springgdsmvn clean package

build the project

CDI archetype requires a Java EE 6 server and uses an embedded GlassFish

cd webappmvn embedded-glassfish:run

With the Eclipse Maven integration (the M2E plugin), you can simply choose one of the archetypes when doing New Maven Project.

mvn war:war

two very easy ways to quickly create a new GraniteDS project

and allows data modifications to be queued up (like a shopping cart),

EXTENDED

is managed by the underlying persistence provider.

an entity is new if it has just been instantiated using the new operator, and it is not associated with a persistence context. It has no persistent representation in the database and no identifier value has been assigned.

a managed entity instance is an instance with a persistent identity that is currently associated with a persistence context.

the entity instance is an instance with a persistent identity that is no longer associated with a persistence context, usually because the persistence context was closed or the instance was evicted from the context.

a removed entity instance is an instance with a persistent identity, associated with a persistence context, but scheduled for removal from the database.

Replacing the current Hibernate 4.0.x jars with a newer version

update the current as7/modules/org/hibernate/main folder

Delete *.index files in as7/modules/org/hibernate/main and as7/modules/org/hibernate/envers/main folders

Remove the older jars and copy new Hibernate jars into as7/modules/org/hibernate/main + as7/modules/org/hibernate/envers/main.

Update the as7/modules/org/hibernate/main/module.xml

as7/modules/org/hibernate/envers/main/module.xml to name the jars that you copied in.

Due to the limited capabilities of the ActionScript 3 reflection API than cannot access private fields, it is necessary to create an externalizable AS3 class (implementing flash.utils.IExternalizable and its corresponding externalizable Java class

In both classes you have to implement two methods

the Gas3 generator can automatically generate the writeExternal and readExternal methods.

With GraniteDS automated externalization and without any modification made to our bean, we may serialize all properties of the Person class, private or not

In order to externalize the Person.java entity bean, we must tell GraniteDS which classes we want to externalize with a

externalize all classes named com.myapp.entity.Person by using the org.granite.hibernate.HibernateExternalizer

you could use this declaration, but note that type in the example above is replaced by

            <include annotated-with="javax.persistence.Entity"/>             <include annotated-with="javax.persistence.MappedSuperclass"/>             <include annotated-with="javax.persistence.Embeddable"/>

: type

annotated-with

Instead of configuring externalizers with the above method, you may use the

feature:

precedence rules for these three configuration options: