Jonathan Lalou's Blog

Archive for the ‘en-US’ Category

Case

After rooting my Nexus S, I tried to flash the ROM, in order to replace the genuine GingerBread with a CyanoGen ehanced version. This worked pretty well, but for a amazing reason I do not know, I missed the so-called “GApps”: GMail, GMaps, etc., this way a Nexus S (or any other Android-driven mobile device) losing any interest. Then, it was the worst catastrophic epiphenomenon I might fear: the Nexus was “bricked”. Indeed, the splash screen, with the Android robot on a skate, did not stop from looping…

Brick, Block and Pitfall

I tried to restore CyanoGen, wipe the memory, etc., but nothing efficient. At last I decided to restore a genuine Gingerbread version.
Here is the puzzling block that stands on the road: a Nexus S does not contain an actual (I mean physical) SD memory card. The “virtual” SD card must be mounted via ADB. But ADB does not recognize the device, since the Nexus is “bricked”. The only access to the Nexus appears to be FastBoot… which does not recognize the /sdcard folder. And the circle is complete.

As you understand, the key is to be able to mount /sdcard, which is sufficient to copy a ROM, and then apply it as a regular update.

Fix

Here we assume you have a minimal knownledge on how to use ADB and FastBoot:

• Download recovery-clockwork-3.0.2.4-crespo.img
• Download GingerBread original ROM: da8206299fe6.signed-soju-ota-121341.da820629.zip
• Switch on your Nexus in recovery mode (sound up and on/off buttons at the same time)
• Select “recovery“
• Connect it to your PC
• On the PC: fastboot boot ~/recovery-clockwork-3.0.2.4-crespo.img
• Your phone reboots with a yellow on black console.
  • Select “mounts and storage” > “mount usb storage”
• Now your PC detects the phone as a regular mass storage device.
  • Copy GingerBread ROM to /sdcard folder.
  • Rename it as update.zip (optionnal, easier for the next step)
• On the PC: fastboot boot ~/recovery-clockwork-3.0.2.4-crespo.img
• On the phone,
  • select the option “apply update“
  • select update.zip
• Restart the phone
• If the phone freezes a long time, shut it down and switch it on again
• Now the regular Nexus splash screen should be OK

Case

Under WebLogic, I deploy RMI services:

[xml] <bean id="fakeRmiServer" class="org.springframework.remoting.rmi.JndiRmiServiceExporter">
<property name="service" ref="fakeInterfaceImpl" />
<property name="serviceInterface" value="lalou.jonathan.FakeInterface" />
<property name="jndiName" value="fakeRmiServer" />
</bean>
<bean id="fakeInterfaceImpl" class="lalou.jonathan.FakeInterfaceImpl" />
[/xml]

The WAR is hosted by a WebLogic 10.3.3 server (this point does not matter).

I retrieve the RMI services on client side, with this Spring config:

[xml] <bean id="fakeServiceClient" class="org.springframework.remoting.rmi.JndiRmiProxyFactoryBean">
<property name="jndiName" value="fakeRmiServer"/>
<property name="jndiEnvironment">
<props>
<prop key="java.naming.factory.initial">weblogic.jndi.WLInitialContextFactory</prop>
<prop key="java.naming.provider.url">t3://localhost:7003</prop>
</props>
</property>
<property name="serviceInterface" value="lalou.jonathan.FakeInterface"/>
</bean>
[/xml]

On launching the client side, I get this error:

[java]java.lang.ClassCastException: Cannot narrow remote object ClusterableRemoteRef(-2462835584319760815S:123.123.123.123:[7003,7003,-1,-1,-1,-1,-1]:JonathanApplication:JonathanAdminServer [-2462835584319760815S:123.123.123.123:[7003,7003,-1,-1,-1,-1,-1]:JonathanApplication:JonathanAdminServer/375])/375 to lalou.jonathan.FakeInterface[/java]

Complete Stacktrace

[java]java.lang.ClassCastException: Cannot narrow remote object ClusterableRemoteRef(-2462835584319760815S:123.123.123.123:[7003,7003,-1,-1,-1,-1,-1]:JonathanApplication:JonathanAdminServer [-2462835584319760815S:123.123.123.123:[7003,7003,-1,-1,-1,-1,-1]:JonathanApplication:JonathanAdminServer/375])/375 to lalou.jonathan.FakeInterface

org.springframework.beans.factory.BeanCreationException: Error creating bean with name ‘fakeServiceClient’ defined in class path resource [lalou/jonathan/java/webservices/jonathan-services.xml]: Instantiation of bean failed; nested exception is org.springframework.beans.BeanInstantiationException: Could not instantiate bean class [lalou.jonathan.java.webservices.FakeServiceWSServer]: Constructor threw exception; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name ‘fakeServiceClient’ defined in class path resource [lalou/jonathan/java/webservices/jonathan-rmi-client-spring.xml]: Invocation of init method failed; nested exception is org.springframework.remoting.RemoteLookupFailureException: Could not narrow RMI stub to service interface [lalou.jonathan.FakeInterface]; nested exception is java.lang.ClassCastException: Cannot narrow remote object ClusterableRemoteRef(-2462835584319760815S:123.123.123.123:[7003,7003,-1,-1,-1,-1,-1]:JonathanApplication:JonathanAdminServer [-2462835584319760815S:123.123.123.123:[7003,7003,-1,-1,-1,-1,-1]:JonathanApplication:JonathanAdminServer/375])/375 to lalou.jonathan.FakeInterface
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateBean(AbstractAutowireCapableBeanFactory.java:883)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:839)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:440)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory$1.run(AbstractAutowireCapableBeanFactory.java:409)
at java.security.AccessController.doPrivileged(Native Method)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:380)
at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:264)
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:221)
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:261)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:185)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:164)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:429)
at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:729)
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:381)
at org.apache.cxf.transport.servlet.CXFServlet.loadAdditionalConfig(CXFServlet.java:171)
at org.apache.cxf.transport.servlet.CXFServlet.updateContext(CXFServlet.java:139)
at org.apache.cxf.transport.servlet.CXFServlet.loadSpringBus(CXFServlet.java:101)
at org.apache.cxf.transport.servlet.CXFServlet.loadBus(CXFServlet.java:70)
at org.apache.cxf.transport.servlet.AbstractCXFServlet.init(AbstractCXFServlet.java:78)
at (…)
at org.mortbay.jetty.servlet.ServletHolder.initServlet(ServletHolder.java:440)
at org.mortbay.jetty.servlet.ServletHolder.doStart(ServletHolder.java:263)
at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:50)
at org.mortbay.jetty.servlet.ServletHandler.initialize(ServletHandler.java:736)
at org.mortbay.jetty.servlet.Context.startContext(Context.java:140)
at org.mortbay.jetty.webapp.WebAppContext.startContext(WebAppContext.java:1282)
at org.mortbay.jetty.handler.ContextHandler.doStart(ContextHandler.java:518)
at org.mortbay.jetty.webapp.WebAppContext.doStart(WebAppContext.java:499)
at org.mortbay.jetty.plugin.Jetty6PluginWebAppContext.doStart(Jetty6PluginWebAppContext.java:115)
at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:50)
at org.mortbay.jetty.handler.HandlerCollection.doStart(HandlerCollection.java:152)
at org.mortbay.jetty.handler.ContextHandlerCollection.doStart(ContextHandlerCollection.java:156)
at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:50)
at org.mortbay.jetty.handler.HandlerCollection.doStart(HandlerCollection.java:152)
at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:50)
at org.mortbay.jetty.handler.HandlerWrapper.doStart(HandlerWrapper.java:130)
at org.mortbay.jetty.Server.doStart(Server.java:224)
at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:50)
at org.mortbay.jetty.plugin.Jetty6PluginServer.start(Jetty6PluginServer.java:132)
at org.mortbay.jetty.plugin.AbstractJettyMojo.startJetty(AbstractJettyMojo.java:454)
at org.mortbay.jetty.plugin.AbstractJettyMojo.execute(AbstractJettyMojo.java:396)
at org.mortbay.jetty.plugin.Jetty6RunWarExploded.execute(Jetty6RunWarExploded.java:170)
at org.apache.maven.plugin.DefaultPluginManager.executeMojo(DefaultPluginManager.java:490)
at org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeGoals(DefaultLifecycleExecutor.java:694)
at org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeStandaloneGoal(DefaultLifecycleExecutor.java:569)
at org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeGoal(DefaultLifecycleExecutor.java:539)
at org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeGoalAndHandleFailures(DefaultLifecycleExecutor.java:387)
at org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeTaskSegments(DefaultLifecycleExecutor.java:348)
at org.apache.maven.lifecycle.DefaultLifecycleExecutor.execute(DefaultLifecycleExecutor.java:180)
at org.apache.maven.DefaultMaven.doExecute(DefaultMaven.java:328)
at org.apache.maven.DefaultMaven.execute(DefaultMaven.java:138)
at org.apache.maven.cli.MavenCli.main(MavenCli.java:362)
at org.apache.maven.cli.compat.CompatibleMain.main(CompatibleMain.java:60)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.codehaus.classworlds.Launcher.launchEnhanced(Launcher.java:315)
at org.codehaus.classworlds.Launcher.launch(Launcher.java:255)
at org.codehaus.classworlds.Launcher.mainWithExitCode(Launcher.java:430)
at org.codehaus.classworlds.Launcher.main(Launcher.java:375)[/java]

Fix

Indeed, this issue appeared with Spring 2.5.4, and was fixed with 2.5.6 release. I let you guess which version I was using…
(cf. Spring 2.5.6 Changelog: * JndiRmiClientInterceptor skips narrowing for RmiInvocationHandler stubs (fixing a regression in 2.5.4)
Therefore, to fix this issue you have to upgrade your Spring version to 2.5.6.

I faced a very embarassing situation: trying to root my Nexus S, I had to unlock the device. My Android SDK was succesfully installed, the drivers too. The device was succesfully recognized by ADB… But fastboot devices failed to detect the device. From this point, it was impossible to unlock the device by launching fastboot oem unlock. I tried many basic solutions, but none worked.

At last, I found this post:
http://forum.xda-developers.com/showthread.php?t=875580

When ADB works but not FastBoot, the solution is to… install PdaNet. Amazing ; but efficient.

Many thanks to BigRick10 from XDA forums!

Following the post on widely used DTDs, here is a list of some XSD (aka XML Schemas):

One month ago, I trained an Indian team, located in Mumbai, on Scrum methology.
Here are the slides of the presentation. It is mainly in English, but with a bit of Hindi in order to please the Indian attendees 😉

The presentation is hosted by Google Docs, under Creative Commons CC-by-cc licence.

DTDs are useful when your XML editor take them in account: detecting errors, suggestions, complete statements… For instance, I save much time with IntelliJ IDEA automatic completion ; unlike, Eclipse amazingly does not implement this feature.

Here is a list of some widely used DTDs:

Tangosol and Log4J DTDs are included within their distribution JARs: you have to extract them or to give their path to IntelliJ IDEA.

This post describes how to install and play with a emulator of GingerBread (Android 2.3)  device on your desktop (or laptop) computer:

• go to this page, download Android SDK related to your system.
• unzip / install it, let’s say in $android-sdk-home
• launch Android SDK Manager (with $android-sdk-home\SDK Manager.exe under Windows, $android-sdk-home/android on other systems)
• on the left panel, select Available Packages, and select Android Repository packages you would like to install, and possibly other third party add-ons.
• go to Virtual Devices >
  • New >
  • give a name, for instance “GingerBread” >
  • Target “Android 2.3.3…” >
  • SD Car Size: 2MiB >
  • leave other options >
  • Create AVD
• wait a little…
• still in Virtual Devices panel, select the AVD you have just created (called hereGingerBread) > Start
• wait… a lot
• enjoy!

EDIT: I could not resist and I have installed HoneyComb, too 😉

Case

You have to enable JMX in an application deployed within WebLogic, so that to access MBeans from Java Visual VM for instance

Solution

On launching WebLogic server instance, add the following properties:

[java]-Dcom.sun.management.jmxremote -Dcom.sun.management.jmxremote.port=8888 -Dcom.sun.management.jmxremote.ssl=false -Dcom.sun.management.jmxremote.authenticate=false[/java]

Case

You need include tools.jar as a dependency in a pom.xml, for instance in order to use Java 5’s annotations and APT. From a “Maven’s view point”, tools.jar is not a regular JAR defined by a groupId and artefactId.

Solution

Add this block in your pom.xml:

[xml]<dependency>
<groupId>com.sun</groupId>
<artifactId>tools</artifactId>
<version>1.6.0_24</version>
<scope>system</scope>
<systemPath>${java.home}/../lib/tools.jar</systemPath>
</dependency>[/xml]

(You can also add it in your settings.xml)

You can do the same for any other “non-regular” JAR, available in your file system.

Case

In a JDBC DAO, I execute a query to retrieve an object. I get this error:

[java]java.sql.SQLException: Wrong data type: NUMBER in statement [CREATE TABLE Jonathan_Table (TableColumn NUMBER][/java]

Stacktrace

[java]java.sql.SQLException: Wrong data type: NUMBER in statement [CREATE TABLE Jonathan_Table (TableColumn NUMBER]
at org.hsqldb.jdbc.Util.throwError(Unknown Source)
at org.hsqldb.jdbc.jdbcPreparedStatement.executeUpdate(Unknown Source)
at com.bnpp.pb.risklayer.services.dao.jdbc.JdbcPrimeRiskServerDaoUnitTest.getDataSet(JdbcPrimeRiskServerDaoUnitTest.java:57)
at org.dbunit.DatabaseTestCase.setUp(DatabaseTestCase.java:154)[/java]

Explanation and fix

My original DB is under Oracle, but my DBUnit tests works on HSQL. Yet, types NUMBER and VARCHAR2 are not available under HSQL, this is why the exception is raised.
To fixe the issue, rewrite your scripts, replacing NUMBER and VARCHAR2 with NUMERIC and VARCHAR.