maven

maven

• to display all the targets:
  mvn -g > toto.txt
  
• List of targets are in project.xml, see "build" target
  
• "dist:" postgoals are described in maven.xml
  
• To add a jar like mysql, you need to add it to project.properties and project.xml
• Maven plugin for eclipse:
• http://download.eclipse.org/technology/m2e/releases

To create an exe from Eclipse

http://stackoverflow.com/questions/574594/how-can-i-create-an-executable-jar-with-dependencies-using-maven Note: use Maven/asembly and not Maven/Packaging

Maven System Properties

mvn assembly:assembly -Dmaven.test.skip=true   (doesn't build tests)

mvn assembly:assembly -DskipTests=true   (doesn't do tests, but build them)

• New Maven project for Eclipse 

1. from the command line:

 mvn archetype:generate -DgroupId=com.yourcompany.engine.api -DartifactId=EngineApi -DarchetypeArtifactId=maven-archetype-quickstart -DinteractiveMode=false

2. cd EngineApi
3. mvn install
4. mvn eclipse:eclipse
5. Import the project into Eclipse as a maven project
6. Right click on the Eclipse project: "Maven / Enable Dependencies Management" then "Maven / Update Project Configuration"

• Maven/Eclipse problem
1. Right-click on your project, select Maven -> Remove Maven Nature.
2. Open you terminal, go to your project folder and do mvn eclipse:clean
3. Right click on your Project and select “Configure -> Convert into Maven Project”

• Create a pom compatible entry to be used as a dependency from a local jar file

mvn install:install-file -DgroupId=org.winterwell -DartifactId=jtwitter -Dversion=2.8.2 -Dfile=/home/lee/tools/JTwitter/jtwitter.jar -Dpackaging=jar -DgeneratePom=true

• if you lost or removed the /target folder
• mvn compile
• or
• mvn package  (creates also the package...)
• Lifecycle phases (generate-test-sources, etc)
• Lifecycle_Reference

• Snapshots
• Use a snapshot of another project in your dependencies
• need to do "mvn clean install" on the project we want a snapshot on
• <properties>
• <whatever-configuration.version>1.0-SNAPSHOT</whatever-configuration.version>
•  see what snapshots you have in
• ~/.m2/repository/fr/...
• if it doesn't find it on local, it gets it from nexus

 

Tomcat survival kit (Tomcat6)

Servlet container, no EJB support

/conf
Ubuntu: /var/lib/tomcat6/conf
W7: C:\Program Files (x86)\Apache Software Foundation\Tomcat 6.0
/usr/share/tomcat/bin/catalina.sh

To see access log on your Tomcat, add the following to your conf/server.xml :

&lt Valve className="org.apache.catalina.valves.AccessLogValve" directory="logs" prefix="localhost_access_log." suffix=".txt" pattern="common"/ &gt

to administer the modules
http://localhost:8080/manager/html
default user: "admin / no pw"
Otherwise, you can add
&lt user name="username" password="secret" roles="standard,manager" / &gt
in /Tomcat 6.0/conf/tomcat-users.xml

default location for war files
/var/lib/tomcat6/webapps
then you do: http://192.168.0.12:8082/sample/

for security reasons, slashes cannot be url encoded, like:
http://127.0.0.1:8080/getimagelist/http%3A%2F%2F
( %3A works but not %2F). See property
org.apache.tomcat.util.buf.UDecoder.ALLOW_ENCODED_SLASH: true|false

for memory setting like

JAVA_OPTS="-Djava.awt.headless=true -server -XX:NewSize=256m -XX:MaxNewSize=256m -XX:PermSize=256m -XX:MaxPermSize=256m -XX:+DisableExplicitGC"

to make sure you don't use openJDK
edit /etc/init.d/tomcat6 and look for JDK_DIRS

if JAVA_HOME is not found when doing sudo /etc/init.d/tomcat start, do:
sudo -E /etc/init.d/tomcat start

other things:
./usr/share/tomcat6/bin/catalina.sh
/var/lib/tomcat6/conf/logging.properties

"too many open files" in catalina

• ulimit -a
  
  • pipe size (512 bytes, -p) 8

.

Android development

when you plug in a nexus and you do
./adb devices
you get:
List of devices attached
???????????? no permissions

What you need to do:
./adb kill-server
sudo ./adb start-server
* daemon not running. starting it now *
* daemon started successfully *
./adb devices
you get:
List of devices attached
HT019P803628 device

Then, if you don't have an emulator running, you can do:
./adb install ../platforms/android-2.1/samples/ApiDemos/bin/apis.apk

To get the debug trace on the host computer:
./adb logcat

Tesseract

To use Tesseract, you need an uncompress Tiff file. To do that:

C:\tools\ImageMagick-6.5.8\VisualMagick\bin\convert.exe c:\tmp4\toto.jpg c:\tmp4\toto.tif
C:\tools\Tesseract>tiffcp -c none c:\tmp4\toto.tif c:\tmp4\unc_toto.tiff
C:\tools\Tesseract>tesseract c:\tmp4\unc_toto.tif out

Go and read the OCR result in out.txt

ImageMagick

• Windows7 / VisualStudio 2008 , To build it, get:
ftp://ftp.imagemagick.org/pub/ImageMagick/windows/ImageMagick-windows.zip unzip
When you open, build, and run: VisualMagick/configure/configure.sln
you get: VisualMagick/VisualStaticMT.sln
Now you can build ImageMagick.
To build a release of an exe using ImageMagick, I ran into VisualStudio libraries conflicts using STATIC_MAGICK. I built the "dynamic" ImageMagick using configure, and then I could have it to work fairly easily.

• To convert pictures using the command line:
  C:\tools\ImageMagick-6.5.8\VisualMagick\bin>convert "C:\Users\x\Downloads\2010-05-16 16.05.43.jpg" -resize 10% toto.jpg
  

• Ubuntu
$tar xvfz ImageMagick.tar.gz
$ cd ImageMagick-6.6.3-1
$ ./configure
$ make
$ sudo make install

ImageMagick-6.7.8-8/utilities/convert DSC_6093.JPG   -resize 40%   out2.jpg

Axis2 Web Service (Tomcat v6)

These are informations that complements
http://people.apache.org/~ruchithf/hw-axis2/
http://www.roseindia.net/webservices/axis2/axis2-client.shtml

Install Tomcat6/Axis2 1.5.1 (Axis2 servlet)
Tomcat configuration on Windows:
C:\Program Files (x86)\Apache Software Foundation\Tomcat 6.0\conf\server.xml

Install eclipse-jee-galileo-SR1-win32.zip (version 3.5)
(to be able to build "Dynamic Web Project")

install "Service Archive Wizard - Eclipse Plug-in" (aar generation). You can get it from the axis2 page: download/tools

Do File/New/"Dynamic Web Project"
(Target Runtime: "Apache Tomcat v6.0")

New Package

New ws Class

Create a file services.xml in WebContent/META-INF (that is what will be exposed as service features).

Create the aar file:
File/New/Others/AxisServerArchiver
- "Class File Location": C:\EclipseWorkSpace\MyWs\build\classes\
- do "not include .class only"
- Next
- Skip WSDL
- Next
- Next
- Set the service XML file: "c:\eclipseworkspace\myws\webcontent\meta-inf\services.xml"
- Next
- "Ouput file location": C:\Program Files\Apache Software Foundation\Tomcat 6.0\webapps\axis2\WEB-INF\services
- WARNING: on Windows 7, eventhough I enter this path, the aar file ends up in
C:\Users\lefla\AppData\Local\VirtualStore
not sure why, must be a privilege problem. I have to copy the aar file in the correct folder afterwards.

Restart Tomcat

if you did:

 public String echo(String value) {
  return "Hello : " + value;
 }

You should see the wsdl generated when click on your service from:
http://127.0.0.1:8082/axis2/services/listServices
(need to "view source" on the blank page on Chrome browser)

and also you should see the echo response (with "null" as parameter)
< ns:echoResponse >
< ns:return > Hello : null < /ns:return >
< /ns:echoResponse >
http://127.0.0.1:8080/axis2/services/myws/echo

If you want a Java client for the Axis WS:
The following command creates the two stubs java files for the client:
(if you use the -t option, it also generates the client java test source code)
C:\tmp>wsdl2java -uri http://127.0.0.1:8080/axis2/services/myws?wsdl -o client

If you want to use a JSP to connect to the WS
You can create a new "Dynamic Web Project"
Reuse the same stub files as in the Java client above in your project
I had to add httpcore-4.0.jar and berkeleydb-1.5.0.jar (sleepycat collections classes) to the project WebContent/WEB-INF/lib.
Put your .jsp files in WebContent
Once done, you can right-click "Export" as a WAR file and put it in
C:\Program Files (x86)\Apache Software Foundation\Tomcat 6.0\webapps\MyJspProject.war
You have to remove the folder MyJspProject in
C:\Program Files (x86)\Apache Software Foundation\Tomcat 6.0\webapps
before restarting Tomcat.
Look at
C:\Program Files (x86)\Apache Software Foundation\Tomcat 6.0\logs\localhost.20xx-xx-xx.log to debug

Please note the typo in the ruchithf apache tutorial. According to the original echo(String value) command, the associated client instruction should be:
request.setValue("Hello world");
and not:
request.setParam0("Hello world");

Some Java Application Servers and Application Frameworks

Application Servers, JSP enabled (javax.servlet container):

• TomCat from Apache Servlet container, no EJBs (Approx 6 Megabytes)
• Jetty no EJBs, light, run on Android
• JBoss from RedHat JSP, Servlets and EJBs
• Blazix from Desiderata Soft JSP, Servlets and EJBs (1.5 Megabytes)
• WebLogic from BEA Systems JSP, Servlets and EJBs (Approx 40 Megabytes)
• WebSphere from IBM JSP, Servlets and EJBs (Approx 100 Megabytes)
• GlassFish from Sun/Oracle JSP, Servlets and EJBs

Application Frameworks

• Spring - for the Java platform and .NET Framework - alternative to, replacement for, or even addition to the EJB model. - light weight
• Tapestry - builds upon the standard Java Servlet API - integrates with any kind of backend, including JEE, Spring and Hibernate. - successor of HiveMind - light weight
• Hibernate - many Java frameworks use Hibernate as a persistence layer, which can generate a database schema at runtime capable of persisting the necessary information. This allows the application designer to design business objects without needing to explicitly define a database schema. - Hibernate is an object-relational mapping (ORM) library for the Java language, providing a framework for mapping an object-oriented domain model to a traditional relational database. Hibernate solves object-relational impedance mismatch problems by replacing direct persistence-related database accesses with high-level object handling functions. - Hibernate's primary feature is mapping from Java classes to database tables (and from Java data types to SQL data types). Hibernate also provides data query and retrieval facilities. Hibernate generates the SQL calls and relieves the developer from manual result set handling and object conversion, keeping the application portable to all supported SQL databases, with database portability delivered at very little performance overhead. - Hibernate can use the XML file or the annotation to maintain the database schema.
• Struts - cleanly separate the model (application logic that interacts with a database) from the view (HTML pages presented to the client) and the controller (instance that passes information between view and model). Struts provides the controller (a servlet known as ActionServlet) and facilitates the writing of templates for the view or presentation layer (typically in JSP, but XML/XSLT and Velocity are also supported). - face competititon from "light weight" MVC frameworks such as Spring MVC, Stripes, Wicket, MyFaces and Tapestry
• JBoss Seam - managed by Gavin King, initiator of Hibernate - Seam combines the two frameworks Enterprise JavaBeans (EJB3) and JavaServer Faces (JSF).
• See also: - java-source.net