Group items tagged

If it is not already loaded in the EntityManager, it is retrieved from the database

is allowed to return a proxy instread of an initialized instance, if the entity has not been loaded in the EntityManager before

In this proxy,

Query object that can then be executed to return a list of entities or a single entity.

Keeping the query and the code that sets these parameters together makes them both easier to understand

Hudson http://wiki.hudson-ci.org/display/HUDSON/FindBugs+Plugin

FindBugs™ - Find Bugs in Java Programs

always have to include this library in either WEB-INF/lib

support for CDI is included in the library granite-cdi.jar

10.1. Configuration with Servlet 3 On Servlet 3 compliant containers, GraniteDS can use the new APIs to automatically register its own servlets and filters and thus does not need any particular configuration in web.xml. This automatic setup is triggered when GraniteDS finds a class annotated with @FlexFilter in one of the application archives:

@FlexFilter(configProvider=CDIConfigProvider.class) public class GraniteConfig { }  

list of annotation names that enable remote access to CDI beans

@FlexFilter declaration will setup an AMF processor for the specified url pattern

@TideEnabled

@RemoteDestination

always declared by default

10.3.2. Typesafe Remoting with Dependency Injection

It is possible to benefit from even more type safety by using the annotation [Inject] instead of In. When using this annotation, the full class name is used to find the target bean in the CDI context instead of the bean name.

Security

integration between the client RemoteObject credentials and the server-side container security

client-side component named

API to define runtime authorization checks on the Flex UI

bindable property

represents the current authentication state

integrated with server-side role-based security

clear the security cache manually with

easy with generics

create

find(

update(

delete(

@TransactionAttribute(TransactionAttributeType.MANDATORY)

implementation or a description of what we did

No more “Just a fix“, “Improvements” or “I made this, this, this and also this” comments.

not what you did

(not what you did)

creates a bad sort of dependency where we need to update the base class every time we make a new derived class. Not good!

if you run them within one transaction like the code below does, you will find that the item list while be empty:

to keep bidirectional associations in sync, JPA leaves more up to the developer.

return a row

3 ways to do this

EntityManger.find()

returns a typed instance of the entity when it is found, null when it is not found

But what if the row isn’t in the database (anymore)?

We get an unchecked exception: NoResultException

We never know for sure what we can expect from our database, so throwing an unchecked exception seems the wrong choice for this use-case

Merge

When the transaction is committed, or if the persistence context is flushed, then the object will be inserted into the database

used to merge the changes made to a detached object into the persistence context

it merges the changes into the persistence context (transaction)

When the transaction is committed, or if the persistence context is flushed, then the object will be updated in the database.

this annotation bypasses the management layer and as such it is recommended only for development and testing purposes

Defining a Managed DataSource

Installing a JDBC driver as a deployment

Installing the JDBC Driver

deployment or as a core module

managed by the application server (and thus take advantage of the management and connection pooling facilities it provides), you must perform two tasks.  First, you must make the JDBC driver available to the application server; then you can configure the data source itself.  Once you have performed these tasks you can use the data source via standard JNDI injection.

recommended way to install a JDBC driver into the application server is to simply deploy it as a regular JAR deployment.  The reason for this is that when you run your application server in domain mode, deployments are automatically propagated to all servers to which the deployment applies; thus distribution of the driver JAR is one less thing for administrators to worry about.

Note on MySQL driver and JDBC Type 4 compliance: while the MySQL driver (at least up to 5.1.18) is designed to be a Type 4 driver, its jdbcCompliant() method always return false. The reason is that the driver does not pass SQL 92 full compliance tests, says MySQL. Thus, you will need to install the MySQL JDBC driver as a module (see below).

Installing a JDBC driver as a module

<module xmlns="urn:jboss:module:1.0" name="com.mysql">  <resources>    <resource-root path="mysql-connector-java-5.1.15.jar"/>  </resources>  <dependencies>    <module name="javax.api"/>  </dependencies></module>

jboss-7.0.0.<release>/modules/com/mysql/main

define your module with a module.xml file, and the actual jar file that contains your database driver

content of the module.xml file

Under the root directory of the application server, is a directory called modules

module name, which in this example is com.mysql

where the implementation is, which is the resource-root tag with the path element

define any dependencies you might have.  In this case, as the case with all JDBC data sources, we would be dependent on the Java JDBC API's, which in this case in defined in another module called javax.api, which you can find under modules/javax/api/main as you would expect.

Defining the DataSource itself

   <datasource jndi-name="java:jboss/datasources/MySqlDS" pool-name="MySqlDS">      <connection-url>jdbc:mysql://localhost:3306/EJB3</connection-url>         <driver>com.mysql</driver>

    <drivers>      <driver name="com.mysql" module="com.mysql">        <xa-datasource-class>com.mysql.jdbc.jdbc2.optional.MysqlXADataSource</xa-datasource-class>      </driver>    </drivers>

jboss-7.0.0.<release>/domain/configuration/domain.xml or jboss-7.0.0.<release>/standalone/configuration/standalone.xml

Step 2 securing some content

create a database that will hold the list of the authorized users along with their password

Create a new directory “auth” and add a new JSP under it, let’s call it “BackOffice.jsp“

enable Shiro into our project by adding a ServletFilter into our Web.xml

 <filter-class>05            org.apache.shiro.web.servlet.IniShiroFilter06        </filter-class>

10    <filter-mapping>11         <filter-name>ShiroFilter</filter-name>12         <url-pattern>/*</url-pattern>13    </filter-mapping>

classpath:shiro.ini

shiro-core

shiro-web

create shiro.ini under resource dir

07ds.jdbcUrl=jdbc:derby://localhost:1527/shiro_schema08ds.username = APP09ds.password = APP

15/auth/** = authcBasic16/** = anon

jdbcRealm.authenticationQuery

jdbcRealm=org.apache.shiro.realm.jdbc.JdbcRealm

setup the jdbc realm, this is where Shiro will find the authorized users

map the URLs to be protected, all the url under /auth should be authenticated with basic HTTP authentication

All the other URLs should be accessed without authentication

Add a new directory under src let’s call it production we will create a new shiro configuration file compatible with MySQL

06ds.serverName = localhost07ds.user = ADM08ds.password = secret12309ds.databaseName = shiro_schema

jdbcRealm which use a MySQL driver

added the appropriate dependency to maven pom.xml

mysql-connector-java

environment.type

staging

13                <jdbc.user>APP</jdbc.user>14                <jdbc.passwd>APP</jdbc.passwd>15                <jdbc.url>jdbc:derby://localhost:1527/shiro_schema</jdbc.url>16                <jdbc.driver>org.apache.derby.jdbc.ClientDriver</jdbc.driver>

src/main/resources

derbyclient

production

environment.type

45                <jdbc.user>ADM</jdbc.user>46                <jdbc.passwd>secret123</jdbc.passwd>47                <jdbc.ds>com.mysql.jdbc.jdbc2.optional.MysqlDataSource</jdbc.ds>48                <jdbc.serverName>localhost</jdbc.serverName>49                <jdbc.databaseName>shiro_schema</jdbc.databaseName>

src/production/resources

To build and run for staging

To build for production

-Denvironment.type=prod

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.