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LadderSoft Research Project

2011-12-05T06:11:00.001-08:00

A research project that enable circuit diagram being built easily even for primary student. That is to unleash the creativity from our kid.

LadderSoft IDE - Draw circuit diagram by just using visualise tool.

Video of robot car coming soon!!!

My First Android App in Samsung Galaxy S

2010-09-03T00:59:00.003-07:00

SQL Best Practise

2010-01-25T06:54:00.000-08:00

Isolating indexed field
//Bad Idea.
Where TO_DAYS(order_created) - TO_DAYS(CURRENT_DATE())>= 7

//Better Idea. CURRENT_DATE() not working for query cache
Where order_created >= CURRENT_DATE() - INTERVAL 7 DAY

//Best Idea
Where order_created >= '11/11/2009' - INTERVAL 7 DAY

Using calculated field
//Bad idea
WHERE email_address LIKE '%.com';

//Better idea
ALTER TABLE CUSTOMERS
ADD COLUMN rv_email_address VARCHAR(80) NOT NULL;
UPDATE customers SET rv_email_address = REVERSE(email_address);
CREATE INDEX ix_rv_email ON customer (rv_email_address(20));

DELIMITER ;;
CREATE TRIGGER trg_bi_cust BEFORE INSERT ON customers
FOR EACH ROW BEGIN
SET NEW.rv_email_address=REVERSE(NEW.email_address);
END;;

//same trigger for BEFORE UPDATE...
//Then SELECT on the new field...
WHERE r_email_address LIKE CONCAT(REVERSE('.com'),'%');

J2ME HttpConnection issue

2010-01-02T22:58:00.000-08:00

J2ME HttpConnection issue when testing with Digi telco and Sony Ericsson W810i

I am wondering why Lwuit-Makeover is able to connect but my own application can not. Then i found out that my application need to run in Internet setting but Lwuit-Makeover just need WAP setting.

If request connection setting from telco, they will send you the following setting.

Digi Streaming
Digi Internet
Digi MMS
Digi WAP

My personal experience about requesting the Digi internet setting. I had make more than 10 times to request Digi Internet setting. First few time failed was because of the "data account full...". Then i browsed to data comm.->data account to delete all the settings. After that, finally i can install successfully with those settings BUT there was no internet setting... So I kept on calling them to send me the internet setting. After few times request i met a guy who suggested to send only internet setting and not like previously send all settings(MMS,WAP,STREAMING, INTERNET...) in once. It work!!! Thanks guy.

Lwuit-Makeover

"Setting for java" can be WAP setting.
Internally this application use com.sun.me.web.request api and Get method to make connection.

My own application

"Setting for java" does not work with WAP setting. It need internet setting.
I use (HttpConnection) Connector.open("http://.."); and writebyte method to make connection.

Is it mean that WAP only work for GET and internet setting is able to work with writebyte? I still need time to figure out what so special in com.sun.me.web.request.

Reference
Avoid Connection Problems with Your Java Applications

SSO : JOSSO VS CAS

2009-12-18T01:44:00.000-08:00

JOSSO, CAS and openSSO are famous Java Single Sign-On in the open source world. The following are some comments on JOSSO and CAS.

CAS

Architecture is simple to install. Security filtering is inside war file.
Only work with SSL.
Easily integrate in Spring security.

CAS + Spring Security integration guide

JOSSO
Architecture is hard to deploy. It consists of gateway and agent. Gateway is the project of SSO/login module. Agent need to be installed in all servers for security filtering. Thus, it tights the configuration to server and bunch of xml files in lib folder of tomcat. The security is configure in the server and not within the project. Even thought installation script is provided but it is just for all(agent, gateway,project) in one server. I got no idea how the configuration should be if more than one server is using...

JOSSO + Acegi integration
Look like outdated because have not upgraded to spring security.

Cross Platform Hibernate @Id Sequence setting

2009-10-04T06:01:00.000-07:00

Cross platform @Id setting
@SequenceGenerator(name = "SEQ_HRMS_EMP", sequenceName = "SEQ_HRMS_EMP", initialValue = 1, allocationSize = 1)
@GeneratedValue(strategy = GenerationType.AUTO, generator = "SEQ_HRMS_EMP")
@Id
@Column(name = "user_id")
private Integer userId;

Schema export from hibernate

MySql
create table HRMS_EMP (
user_id integer not null auto_increment,

MySql will ignore the generator = "SEQ_HRMS_EMP" setting because MySql does not have sequence.
Postgres
create sequence SEQ_HRMS_EMP;
Oracle
create sequence SEQ_HRMS_EMP;

Fluent Interface Design Pattern in IBatis3

2009-09-07T07:18:00.000-07:00

I found the following coding style in ibatis3 tutorial. Look interesting about the coding.

private String selectPersonSql() {
BEGIN(); // Clears ThreadLocal variable
SELECT("P.ID, P.USERNAME, P.PASSWORD, P.FULL_NAME");
SELECT("P.LAST_NAME, P.CREATED_ON, P.UPDATED_ON");
FROM("PERSON P");
FROM("ACCOUNT A");
INNER_JOIN("DEPARTMENT D on D.ID = P.DEPARTMENT_ID");
INNER_JOIN("COMPANY C on D.COMPANY_ID = C.ID");
WHERE("P.ID = A.ID");
WHERE("P.FIRST_NAME like ?");
OR();
WHERE("P.LAST_NAME like ?");
GROUP_BY("P.ID");
HAVING("P.LAST_NAME like ?");
OR();
HAVING("P.FIRST_NAME like ?");
ORDER_BY("P.ID");
ORDER_BY("P.FULL_NAME");
return SQL();
}

IceSoft Name Card

2009-09-01T08:03:00.001-07:00

Load Balance by using mod_jk + apache server2.0

2009-08-11T08:40:00.000-07:00

1)Add following code to C:/Program Files/Apache Group/Apache2/conf/httpd.conf

# Include mod_jk configuration file

Include "C:/Program Files/Apache Group/Apache2/mod_jk/mod_jk.conf"

2)Create mod_jk.conf to C:/Program Files/Apache Group/Apache2/mod_jk/mod_jk.conf

# Load mod_jk module

# Specify the filename of the mod_jk lib

LoadModule jk_module "C:/Program Files/Apache Group/Apache2/mod_jk/mod_jk-1.2.28-httpd-2.0.52.so"

# Where to find workers.properties

JkWorkersFile "C:/Program Files/Apache Group/Apache2/mod_jk/workers.properties"

# Where to put jk logs

JkLogFile "C:\Program Files\Apache Group\Apache2\mod_jk/mod_jk.log"

JkLogLevel info

JkLogStampFormat "[%a %b %d %H:%M:%S %Y] "

JkOptions +ForwardKeySize +ForwardURICompat -ForwardDirectories

JkRequestLogFormat "%w %V %T"

#Mount your webapps eg WebApplication1 using JkMount

# Add shared memory.

# This directive is present with 1.2.10 and

# later versions of mod_jk, and is needed for

# for load balancing to work properly

JkShmFile /var/log/apache2/jk.shm

JkMount /* router

JkMount router

Order deny,allow

Deny from all

Allow from 127.0.0.1

</Location>

3) Create worker.properties on C:\Program Files\Apache Group\Apache2\mod_jk\worker.properties

# The advanced router LB worker

worker.list=router

# Define a worker using ajp13

worker.worker1.port=8009

worker.worker1.host=127.0.0.1

worker.worker1.type=ajp13

worker.worker1.lbfactor=1

# Define preferred failover node for worker1

worker.worker1.redirect=worker2

# Define another worker using ajp13

worker.worker2.port=8009

worker.worker2.host=127.0.0.1

worker.worker2.type=ajp13

worker.worker2.lbfactor=1

# Disable worker2 for all requests except failover

worker.worker2.activation=disabled

# Define the LB worker

worker.router.type=lb

worker.router.balance_workers=worker1,worker2

4) Download iso mod_jk-1.2.28-httpd-2.0.52.so from http://www.apache.org/dist/tomcat/tomcat-connectors/jk/binaries/win32/jk-1.2.28/

to C:\Program Files\Apache Group\Apache2\mod_jk\

5) For sticky session

Edit tomcat's server.xml for all tomcat

Comment

Uncomment <Engine name="Standalone" defaultHost="localhost" jvmRoute="worker1">

References

Step by step - http://www.devside.net/guides/windows/tomcat

Help for worker.properties

http://tomcat.apache.org/connectors-doc/reference/workers.html

http://tomcat.apache.org/connectors-doc/generic_howto/loadbalancers.html

JSF1 RichFaces Performance Tuning

2009-08-08T03:34:00.000-07:00

1) JSF components tree state takes big enough memory. In the server-side
state saving ( default JSF behavior ) these objects are stored in the
session. For a many concurrent user connections every user gets own
session object. Possible solution - switch to the client-side state saving.
<context-param>
<param-name>javax.faces.STATE_SAVING_METHOD</param-name>
<param-value>client</param-value>
</context-param>

Other possible solution is Facelets behavior that allows to build view
before request processing instead of state saving, but that solution has
sometimes unpredictable side effects. Use web.xml init parameter
together with the <f:view transient="true" > attribute.
<context-param>
<param-name>facelets.BUILD_BEFORE_RESTORE</param-name>
<param-value>true</param-value>
</context-param>
As an intermediate solution, it is makes sense to create custom FaceletsViewHandler subclass with special state processing for a some pages like menus which does not depends for a saved state. That custom handler could call buildView method instead of real restoreView procedure for a such pages.
2) Facelets library in the "debug" mode stores information about
components and beans up to 5 times for an every user. To disable this mode:
<context-param>
<param-name>facelets.DEVELOPMENT</param-name>
<param-value>false</param-value>
</context-param>

3) Most filters use buffering for request processing. According to the
profile information, these buffers took big enough memory in the
application. I see a buffer-related parameter in the RichFaces Ajax filter:
<init-param>
<param-name>maxRequestSize</param-name>
<param-value>100000</param-value>
</init-param>
For a production server, it makes sense to reduce value to a real page
size or remove that parameter at all.
4) TIDY xml filter is DOM-based, thus it requires a lot of memory. It
would be better to use more optimized "NONE" or "NEKO" one :
<context-param>
<param-name>org.ajax4jsf.xmlparser.ORDER</param-name>
<param-value>NONE</param-value>
</context-param>

JSF Thing to cater for if you are JSF Developer

2009-07-28T20:15:00.000-07:00

It is because JSF is component base(not simple as MVC direct request to action in controller layer).

Problem of coding style

1) DB query inside getter method of backing bean.

public List getUserRole(){
return userRoleDao.queryAllUserRole();
}

Issue : Getter may be call in restore view or apply request value or render response phase

Table component, it wil cause the data being query 2 times.
inputText/radio etc. component, it will check the previous submitted value store(JSF will store previous submitted value automatically) inside the inputText. If it is null, it will call the getter in backing bean to retrieve the value.

Following was the log.
[ INFO] 29-07-09 11:10:34 : BEFORE RESTORE_VIEW(1)
[ INFO] 29-07-09 11:10:34 : AFTER RESTORE_VIEW(1)
[ INFO] 29-07-09 11:10:34 : BEFORE APPLY_REQUEST_VALUES(2) Hibernate: select this_.role_name as ...
[ INFO] 29-07-09 11:10:34 : AFTER APPLY_REQUEST_VALUES(2)
[ INFO] 29-07-09 11:10:34 : BEFORE PROCESS_VALIDATIONS(3)
[ INFO] 29-07-09 11:10:34 : AFTER PROCESS_VALIDATIONS(3)
[ INFO] 29-07-09 11:10:34 : BEFORE UPDATE_MODEL_VALUES(4)
[ INFO] 29-07-09 11:10:34 : AFTER UPDATE_MODEL_VALUES(4)
[ INFO] 29-07-09 11:10:34 : BEFORE INVOKE_APPLICATION(5)
[ INFO] 29-07-09 11:10:34 : AFTER INVOKE_APPLICATION(5)
[ INFO] 29-07-09 11:10:34 : BEFORE RENDER_RESPONSE(6) Hibernate: select this_.role_name ...
[ INFO] 29-07-09 11:10:35 : AFTER RENDER_RESPONSE(6)

Solution : Only query DB when it is in render response phase.

public List getUserRole(){
if (FacesContext.getCurrentInstance().getRenderResponse())
return userRoleDao.queryAllUserRole();
else
return null;
}

or

public List getUserRole(){
if ( userRoleList!=null)
userRoleList = userRoleDao.queryAllUserRole();

return userRoleList;
}

JSF 2 going to have MVC lifecycle!!!

JSF 1 Immediate property

2009-07-28T19:15:00.000-07:00

Immediate = true , it will no proceed to Validations phase. It suit for Cancel button that you don't want any validation(require=true etc.) on the page but it will reach to action of Cancel button. Since those parameters of inputText do not go through validation phase, it also will not update to your variable in backing bean. There is a workaround solution to retrieve those values.

hyperlink immediate = true. that only accepts values from a specific control (the immediate property for all of these components would be true).

App Server Performance Tuning Reference

2009-06-30T07:03:00.000-07:00

Garbage Collection Guide

http://java.sun.com/javase/technologies/hotspot/gc/gc_tuning_6.html#generation_sizing

Performance Tuning Tips

http://www.javaperformancetuning.com/tips/appservers.shtml#REF12

Jboss

http://www.mastertheboss.com/en/jboss-application-server/113-jboss-performance-tuning-1.html

Jboss Tips

32bit OS max heap size is 2GB Ram. Inorder to increase the heap size, add jboss instance.

Attractive Tourism in Google Earth

2009-06-24T00:18:00.000-07:00

Create tour in google earth for all tourist attraction.

Bring tourist to go arround tourist attraction.
Youtube included for more interactive.
Search engine looking for place to go example shopping, outlet, night market,night scene, beach...

Thing to do

Collect tourist attraction information.
Build all the 3D building for tourist attraction in google earth. It not only building. 3D can be table, swimming poor, car... All Objects.
Make movie in youtube.

Money channel Hotel, Restaurant, Government Tourism

Specialist tourism IT department for government.
Search nearest hotel.
Build 3d hotel for them. Information and youtube intro the hotel. Then bring customer to their hotel home page.
Ocean feature in google earth is focus on educate ppl importance of environmental protection. Help government to educate ppl, submit geographical data for research. See the youtube Google earth 5 launch event to know more about ocean.

Technically work!!! Totally not an issue.

It easier than war game in google earth. Start this phase first for training our guy to get use to google earth technology. Prepare for the second phase of social networking and war game.

Progress

Learning

Using SketchUp to draw 3d building and integrate to google earth.
Export kmz file for ppl download.

Next - How to import it to google earth to make it share with all users. No need download individual file to view. Because it can be public in google servel or private in individual kmz file.

Vista Setup Guide

2009-06-18T10:14:00.000-07:00

1) Step

UAC Popup "Windows needs your permission to continue":

How to quickly disable User Account Control (UAC):

Click the round blue Windows Start button. Now click Control Panel
From the Control Panel, click User Accounts and Family Safety (or User Accounts if your in classic view)
Click the option to Turn User Account Control on or off
Uncheck the box next to Use User Account Control (UAC) to help protect your computer and click OK
Restart when prompted

2 )Step Configuration for Vista accept XP folder
Vista uses the more-picky NTLMv2 network protocol, while XP uses NTLMv1. The answer is, therefore, to switch Vista to use NTLMv1.

Here's the Mac-oriented post which tells how to modify Vista: http://www.broadbandreports.com/faq/14837

Rewriting it in Windows terminology, it would read:

To allow Vista to talk to your XP/2000/Linux shares, you must allow Vista to authenticate via NTLMv1:

If you have Windows Vista Home Basic/Premium:
Open the registry editor. Navigate to

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Lsa.

There will be a value called LmCompatibilityLevel. Set that to DWORD 1. Reboot and try to connect again.

Research 1 on Google earth

2009-06-14T04:21:00.000-07:00

Thing can be on google earth

Create 3d model on google earth by using sketchup

Google Earth can be develop using Java Gwt API for Google Map

The Google Maps API provides a convenient JavaScript API which allows you to add mapping functionality to your application. The Google Maps library for GWT allows you to access this JavaScript API from Java code compiled with the GWT compiler.

Documentation for GWT Google Map

KML in Google Earth

KML is a file format used to display geographic data in an Earth browser, such as Google Earth, Google Maps, and Google Maps for mobile. You can create KML files to pinpoint locations, add image overlays, and expose rich data in new ways. KML is an international standard maintained by the Open Geospatial Consortium, Inc. (OGC).

KML Interactive Sampler You can see what can be done in google earth

IceSoft Logo

2009-05-06T21:24:00.001-07:00

By Celine

Which one better?

World War on Google Earth

2009-05-04T23:51:00.000-07:00

What can be done on google earth? Thing come out from my mind is game but it can link with the hottest idea in 2000 century which is social networking. Since google eart provide us the virtual earth. We can do anything on top of it right. We can rotate,split,stretch and finally boom the earth. Cool men...So why not we create a World War Game on Google Earth. since google already provide drawing feature for user to draw building on it. Then we just need to make animation on it. Create 3D ppl on it.

War Game
Player can register their house and draw their house on it. Then trying to protect their house and country. Thus, the war location is same as our earth. Player can be soldier when there is a war or can attact another country.

Social networking
Individual have their own identity in the virtual world. So you can do anything that you are not dare to do in real world for example boy wanted to tackle a girl but he scare on real worth. It can be done there. Whatelse...

Animation on Google Earth
Finally i found out the google earth api and demo

JBoss Clustering with Microsoft Network Load Balancing

2009-01-12T08:27:00.000-08:00

Jboss configuration
Changes in jboss-service.xml
C:\Server\jboss-4.2.2\server\all\deploy\jboss-web-cluster.sar\META-INF\jboss-service.xml
1) delete <Config> <UDP> .... </Config>
2) paste the following code to the same area of deleted code.
The initial_hosts highlighted bellow is to specify other server's IP.
3) Sample jboss-service.xml is located in “NLB Manager PrintScreen & Config File” folder

<config>
<TCP start_port="7810" loopback="true" bind_addr="${bind.address}"
tcp_nodelay="true"
recv_buf_size="20000000"
send_buf_size="640000"
discard_incompatible_packets="true"
enable_bundling="false"
max_bundle_size="64000"
max_bundle_timeout="30"
use_incoming_packet_handler="true"
use_outgoing_packet_handler="false"
down_thread="false" up_thread="false"
use_send_queues="false"
sock_conn_timeout="300"
skip_suspected_members="true"/>
<TCPPING initial_hosts="192.168.0.7[7810]" port_range="3"
timeout="3000"
down_thread="false" up_thread="false"
num_initial_members="3"/>
<MERGE2 max_interval="100000"
down_thread="false" up_thread="false" min_interval="20000"/>
<FD_SOCK down_thread="false" up_thread="false"/>
<FD timeout="10000" max_tries="5" down_thread="false" up_thread="false" shun="true"/>
<VERIFY_SUSPECT timeout="1500" down_thread="false" up_thread="false"/>
<pbcast.NAKACK max_xmit_size="60000"
use_mcast_xmit="false" gc_lag="0"
retransmit_timeout="300,600,1200,2400,4800"
down_thread="false" up_thread="false"
discard_delivered_msgs="true"/>
<pbcast.STABLE stability_delay="1000" desired_avg_gossip="50000"
down_thread="false" up_thread="false"
max_bytes="400000"/>
<pbcast.GMS print_local_addr="true" join_timeout="3000"
down_thread="false" up_thread="false"
join_retry_timeout="2000" shun="true"
view_bundling="true"/>
<FC max_credits="2000000" down_thread="false" up_thread="false"
min_threshold="0.10"/>
<FRAG2 frag_size="60000" down_thread="false" up_thread="false"/>
<pbcast.STATE_TRANSFER down_thread="false" up_thread="false" use_flush="false"/>
</config>

4) change REPL_ASYNC to REPL_SYNC
<attribute name="CacheMode">REPL_SYNC</attribute>

Changes in cluster-service.xml
C:\Server\jboss-4.2.3.GA\server\all\deploy\cluster-service.xml
1) delete <Config> <UDP> .... </Config>
2) paste the following code to the same area of deleted code.
The initial_hosts highlighted bellow is to specify other server's IP.

<Config>
<TCP start_port="7800" loopback="true" bind_addr="${bind.address}"
tcp_nodelay="true"
recv_buf_size="20000000"
send_buf_size="640000"
discard_incompatible_packets="true"
enable_bundling="false"
max_bundle_size="64000"
max_bundle_timeout="30"
use_incoming_packet_handler="true"
use_outgoing_packet_handler="false"
down_thread="false" up_thread="false"
use_send_queues="false"
sock_conn_timeout="300"
skip_suspected_members="true"/>
<TCPPING initial_hosts="192.168.0.7[7800]" port_range="3"
timeout="3000"
down_thread="false" up_thread="false"
num_initial_members="3"/>
<MERGE2 max_interval="100000"
down_thread="false" up_thread="false" min_interval="20000"/>
<FD_SOCK down_thread="false" up_thread="false"/>
<FD timeout="10000" max_tries="5" down_thread="false" up_thread="false" shun="true"/>
<VERIFY_SUSPECT timeout="1500" down_thread="false" up_thread="false"/>
<pbcast.NAKACK max_xmit_size="60000"
use_mcast_xmit="false" gc_lag="0"
retransmit_timeout="300,600,1200,2400,4800"
down_thread="false" up_thread="false"
discard_delivered_msgs="true"/>
<pbcast.STABLE stability_delay="1000" desired_avg_gossip="50000"
down_thread="false" up_thread="false"
max_bytes="400000"/>
<pbcast.GMS print_local_addr="true" join_timeout="3000"
down_thread="false" up_thread="false"
join_retry_timeout="2000" shun="true"
view_bundling="true"/>
<pbcast.STATE_TRANSFER down_thread="false" up_thread="false" use_flush="false"/>
</Config>

</attribute>
<depends>jboss:service=Naming</depends>
</mbean>

3) replace the HAJNDI portion with following code. Highlighted word is the only changes.

<mbean code="org.jboss.ha.jndi.HANamingService"
name="jboss:service=HAJNDI">

<depends optional-attribute-name="ClusterPartition"
proxy-type="attribute">jboss:service=${jboss.partition.name:DefaultPartition}</depends>

<attribute name="BindAddress">${bind.address}</attribute>

<attribute name="Port">1100</attribute>

<attribute name="RmiPort">1101</attribute>

<attribute name="Backlog">50</attribute>

<depends optional-attribute-name="LookupPool"
proxy-type="attribute">jboss.system:service=ThreadPool</depends>


<attribute name="DiscoveryDisabled">false</attribute>

<attribute name="AutoDiscoveryBindAddress">${bind.address}</attribute>

<attribute name="AutoDiscoveryAddress">${jboss.partition.udpGroup:230.0.0.4}</attribute>
<attribute name="AutoDiscoveryGroup">1102</attribute>

<attribute name="AutoDiscoveryTTL">16</attribute>

<attribute name="LoadBalancePolicy">org.jboss.ha.framework.interfaces.RoundRobin</attribute>



</mbean>

4) Sample cluster-service.xml is located in “NLB Manager PrintScreen & Config File” folder

Start your Jboss with the following command line.
Located in NLB Manager PrintScreen & Config File/runCluster.bat.
Modify the highlighted IP. 192.168.0.225 is virtual IP and 192.168.0.7 is local IP.
run -Dignore.bind.address=true -b 192.168.0.225 -Dbind.address=192.168.0.7 -c all

Change URL of GWT output

2009-01-04T22:47:00.000-08:00

One of the issue in gwt is the url. If your package of app.gwt.xml is in com.y2bid.gwt, then your url of html output from compiler will be http://127.0.0.1/com.y2bid.gwt.app/index. Is it not nice!!! Inorder to avoid the package become URL you can choose the following methods.

3 Methods
1) < module rename-to="app" > . This way will give you a bit problem in hosted mode because of the url different and problem with your url in web.xml

2) Create new package and inherit the actual gwt.xml file.

3) Compiled all to javascript then rename the folder. This will cause you hard to do testing with your server if you have url mapping in web.xml

Conclusion
Method No. 2 is the best to fulfill all the need(Testing in hosted mode and deploy).

Sanjiv Comment on ppl argue with Pure Gwt and Javascript Wrapper ( SmartGWT )

2008-12-14T08:25:00.001-08:00

Compile output size and runtime performance are two separate issues. A
third party widget written in GWT Java, regardless of how small it compiles down
to, doesn't magically make it run fast. Nor does it make it magically render
perfectly on all browsers. As an example a TableGrid written in GWT Java could
still perform really poorly, and not display consistently on all browsers.
There are obviously several aspects to GWT that helps avoid leaks and such
but this does not mean that any third party code written in GWT is
100% leak free. The GWT 1.6 event API is really neat and SmartGWT users
it. Well written code is what will perform well and display consistently
across various browser.
On the issue of performance, there are numerous posts
made by paying GXT users that the performance of GWT-Ext is still better than
GXT. You can search their forums. This is not to suggest that performance
improvements cannot be made in SmartGWT. If you can give specifics, it would
certainly help in resolving them. But without specifics like whether it was the
initial load time, performance of specific widgets etc it will be difficult to
act on. Feel free to post on the SmartGWT forums or create an issue on the
smartgwt google code project.
On the issue of compile output size : The
SmartClient library is extremely stable and developed over the past 8 years.
If you peruse their forums, you will find that pretty much all questions
are met with an answer explaining how the user can accomplish what they're
trying to do. Their library is virtually bug free. I realize this is a strong
statement, but its true. Only some 4-5 issues were patched
post-release. Compare this to the bugs forum of any of
your favorite libraries. SmartGWT will inherit these attributes
once its past the few initial minor releases and issues are flushed out during
this period. Due to the high level of stability of SmartClient, it can be
viewed as the kernel of your web app which should be configured to be
gzipped with an "Expires Never" header for a given version. This means that the
browser will cache the "kernel" (SmartClient JS files) and the only code that
gets downloaded is your application code, and not any code related to the widget
/ framework. Future releases of SmartGWT will provide a GWT linker that only
pulls in the required files so this should cut down the total size of the
application.
The SmartGWT showcase has some 250 samples which is 6 times more
than the GXT showcase so its not quite apples to apples when it comes to initial
load time.
Finally please read my blog entry http://www.jroller.com/sjivan/entry/smartgwt_1_0_released if
you haven't already done so. I go over the SmartGWT fundamentals, the concept of
a DataSource and how it will lead to a cleaner architecture and can cut
application code significantly. I mention how a master detail page can be
written in as little as 10 lines using a reusable DataSource definition that
describes an entity / model class. Plus the reduced number of lines of code on
the server as well.This is the first release of SmartGWT and while it is quite
stable and has been tested and used by early adopters for the past four weeks,
users can expect any rough edges / bugs / performance issues / better skins etc
to be ironed out over the course of the next few minor releases.As mentioned
earlier, if users have found a library that meets their needs, thats great and
there's no need to look further. And for the others, feel free to evaluate
SmartGWT to see if it helps meet your requirements. If you feel that there are
things that can be improved please post on the SmartGWT forum or create an issue
on the google code project page.

Nice Icon from dryicons.com

2008-12-13T03:59:00.000-08:00

Recommended icon download site.

http://dryicons.com

Gwt UI Component with Fluent Interface Pattern

2008-12-12T19:17:00.000-08:00

Fluent Interface pattern Fluent Interface is come from Martin Fowler. These types of design pattern are often utilized to create configurations for your objects but can progress into an internal Domain Specific Language or DSL.

I will use GWT as a sample to point out the issue of Swing like development with HTML\tag style for UI programming. In GWT/Swing like coding style, have you found out that the number of line of code is much more than tag style. Look at the following explanation.

Gwt Button with out Fluent Design
Button disabledButton = new Button();
disabledButton.ensureDebugId("cwBasicButton-disabled");
disabledButton.setEnabled(false);
disabledButton.setWidth("11");
disabledButton.setHeight("11");
disabledButton.setTitle("Disable Button");
disabledButton.setFocus(true);
//Come on!!! still set again.. :( ..How many line already!!! that is just one UI component...
.....
...
..
.

HTML / Tag style
All the properties can be in one line and optional.
< button title="Disable Button" width="11" focus=" true" height=" 11" enabled=" false" ensuredebugid="cwBasicButton-disabled" />

Gwt Button with Fluent Design
Button disabledButton = new Button()
.ensureDebugId("cwBasicButton-disabled").setEnabled(false).setWidth("11").setHeight("11").setTitle("Disable Button").setFocus(true) ;

Fluent like coding style is something like tag/annotation style of code. It is good to configure an object.

Constructor way of coding
No wait a minute, We can use Constructor to passin the properties so it can be in one line of code.
Maybe you can create constructor for the Button object with all the properties but how many combination of properties you can create. Bad design because it is not easy to read.
Button disabledButton = new Button("cwBasicButton-disabled", true, true); //what is the true true for? Which one is enabled? Which one is focus?

public Button ( String ensureDebugId, boolean enabled, boolean focus){...}
public Button ( String ensureDebugId, boolean enabled, String title ){...}
public Button ( String ensureDebugId, boolean enabled, boolean focus){...}
// you can create somemore for other properties...if you are hardworking.

Make Button with Fluent Interfaces Design Pattern
So in order for GWT/Swing like coding style to solve all this issues and to minimise the number of line of code and readability. Fluent interfaces pattern has to be implemented.
All the UI component should be coded in the following way. All setters have to return this own for the subsequent statement to call again.

Button SetTitle(String title){
this.title= title;
return this;
}
Button SetEnabled(boolean enabled){
this.enabled= enabled;
return this;
}
...
..// for all the setter of the properties

Button with Java5 Annotation
With the Java5 Annotation support, you can easily configure an object in Attribute Oriented Programming way. But do you think gwt support annotation in runtime mode? The answer is no. But we can use it via gwt generator wich mean in the compile time.
@ButtonProperties( ensureDebugId="cwBasicButton-disabled", enabled= false, width=11, height=11, title="Disable Button", focus=true )
Button button = new Button();

Fluent Interfaces Pattern in SQL
let see how it can be in Sql.
Query = q = new Query()
.select("name","age").from("Student").where("age").between(12,20).where("gender").is("M")
This can be easily refactor and avoid typo error. Sound good right!!!

Finally, i hope our programming trend is going to attribute oriented programming and fluent Interfaces Pattern. THE WORLD IS JUST CONFIGURE

GWT 1.6 going to release soon

2008-12-12T08:21:00.000-08:00

Happy to see that GWT 1.6 going to release soon. Estimated on Q1 2009. Compiler performance improvements is a high demand feature in gwt group from all GWT developer. Hopefully it can reduce the compilation time to 50% and more. Other than that will be Developer Guided Code splitting, to avoid download all javascript at the first load.

Release 1.6

New compiled file deployment structure

Easily compile into a war file structure, making it easy to deploy your compiled GWT application into standard servlet containers

Migration from Tomcat to Jetty hosted mode server

A more pluggable architecture for the hosted mode server will enable developers to use servlet containers other than Tomcat with the Hosted Mode browser

Uniform event handlers

Event handlers will be implemented in a uniform fashion across all widgets, with listeners deprecated

DatePicker, LazyPanel migrated in from incubator

New widgets from the incubator

String performance improvements

StringBuilder uses deferred binding to optimize string appends per-browser

Compiler performance improvements

1.6 will introduce parallel permutation compilations and other performance tweaks for faster compiles

Post 1.6

Developer Guided Code splitting

Developer guided code splitting is a mechanism that allows developers to specify asynchronous split points in their code where the code base can be split and downloaded in different chunks. This is currently an R&D project but looks promising.

Analysis of compiled code, aka Story of your compile (SOYC)

Aims to give developers concrete information about their compiled JavaScript, such as which Java classes are generating the most JavaScript code.

In-browser hosted mode, aka Out-of-process Hosted Mode (OOPHM)

In-browser hosted mode will allow GWT developers to debug their apps within a browser rather than GWT's hosted mode browser

UI Binder

The UI Binder will allow the creation of UI elements in a declarative fashion. Watch for UI Binder to land in the GWT incubator soon.

Client Bundle

Client Bundle implements the power of deferred binding used in Image Bundle in a generic fashion so that it can be used on many resources. These include TextResource, ImageResource, and CSSResource

RPC performance improvements

Ongoing work to improve the performance of RPC

Sanjiv is back with SmartGWT

2008-11-19T06:35:00.000-08:00

The God of GWT wrapper is back. Sanjiv is going to wrap another 3rd party UI library which is SmartClient. This time the SmartClient is more rich than Ext Js. But i felt slow when browsing through the showcase. It is still the problem of GWT. Or it because of wrapper wich does not take advantage of GWT javascript optimisation in compilation. Here is the showcare.

After the Issue happened in GwtExt, the first thing we need to see is the licensing issue. SmartGWT and the underlying SmartClient library are LGPL, free for use inside commercial, closed source applications without payment of any kind. Sound ok. Hope he found the right way to go this time.

SmartClient does provide web visual builder also. It sound really comprehensive. Here is the video to showoff.

SmartClient showcase->http://www.smartclient.com/index.jsp#_Welcome

Some of the points and question coming out in my mind...

1)Is GwtExt going to end soon?

2)It is just the wrapper like GwtExt. It does not fully use the power of GWT like javascript optimisation and more...

3)Can Sanjiv be trusted this time?

If you are just the simple user. you should use SmartClient. If you are professional technology java guy. you should not consider this because you learn nothing. I still will choose ExtGwt. It is because it build up from native google api. We can learn the code from there and change the code if anything happen which you can't do anything with GwtExt and this SmartGWT.

Comparison of Jasper and Birt

2008-11-19T00:29:00.000-08:00

There are 2 famous Java Reporting tools which are Jasper( free ) / Jasper server and Birt( free ) from Eclipse/Birt Exchange from Actuate. You can consider the following points when selecting the java reporting for your project.

Drawback of Birt
1) Jasper ui is pixel base so you can get exactly what you see what you get but Birt is not. Issue in receipt printing for those location and allignment is fixed.
2) Eclipse designer problem. You have to erase the whole filter and add again. The changes will not be reflected if you just modify from there.
3) Output is different in Eclipse designer and real deployment when play with complex subreport.
4) White space between row.

Drawback of Jasper
1) The subreport has to use whole row in main report but Birt not neccessary. Not really consider drawback of jasper because subreport is not really useful because of the performance issue.
2) File size is big for embedding to your project because of the wizard and view page (i think).

Advantage of Birt
1) Provide Wizard to create input screen in ajax.
2) View reporting page is provided so programmer no need to code the output screen. But have to do the security part.

Conclusion

Jasper is the winner because it will not create many issue like Birt for programmer.

Google Docreader : Change root label of tree

2008-11-13T05:03:00.000-08:00

At the beginning, the label is follow your project name which can not contain any space. Thus, it can not be meaningfull name for your document description.

After i google arround the world, secret behind is you need to create a wiki page in your google project hosting named DisplayName.

Example : http://code.google.com/p/jimmy6/wiki/DisplayName