Tong Sun's blog

Table not found in statement

2011-09-23T10:46:00.000-07:00

When creating a table in Grails, I used "password" as a column name, then when connecting to Oracle and try to create table for the first time, I got the following error:

java.sql.SQLException: Table not found in statement [...

After searching online and randomly trying to fix it, I finally come to change the column name to "myPassword", and it worked. I could only wish the error message could be more helpful.

STS and Grails error

2011-09-16T09:07:00.000-07:00

When I changed the .grails and .ivy2 folder from my home directory to another location, I got the following compiling error:
The type groovy.lang.GroovyObject cannot be resolved. It is indirectly referenced from required .class files.

To solve this problem, right click the project, grail tools -> refresh dependencies fixed it.

Windows CPU 100% all the time

2010-04-28T13:19:00.000-07:00

I'm using Windows XP and the CPU 100% problem was bothering me for a while. I tried to use "Windows Update" site to disable the automatic update, but the wuauclt.exe always comes back a few minutes later after I kill it. I tried to go to "Control Panel", turn off Automatic Updates, that didn't help either.

Finally, I tried go to Start, then Run Services, on Automatic Updates, disable it. From then on, I'm wuauclt.exe free!

MyEclipse upgrade - making a war file

2009-07-02T08:45:00.001-07:00

In the older version of MyEclipse, we used JBoss plugin for Eclipse for .war file generation. But after the upgrade to MyEclipse 7.1, the JBoss plugin simply doesn't work anymore.

Of course, we could always write our own deployment descriptor, run ANT, and generate the .war file. But that also means install ANT on every developer's local machine, configure the path, go to command line every time, not something easy for everyday life.

So, after some research, here's the alternative:

Although MyEclipse does not require Tomcat plugin, we could just set the path and run different versions of Tomcat. But if we add the Tomcat plugin, we could generate .war file!

Step 1: Right click the project name -> properties

Step 2: Choose Tomcat from the bottom, then click Export to WAR settings.

Step 3: Browse to the correct directory and give the WAR file name.

Step 4: Click Apply and close the properties page.

Step 5: Right click the project name -> Tomcat Project -> Export to the WAR file sets in project properties.

Now we have a .war file ready to be deployed.

XSL-FO checkbox using unicode

2009-07-02T08:21:00.000-07:00

When using xsl-fo to generate PDF, according to FO documentations, the best way is to use unicode fonts instead of using fo:external-graphics. After searching the web, I didn't find the best solution, but found a lot of useful information. The existing solution is, there is a way to draw a unchecked box using font "ZapfDingbats", but there is no checked box. For the unchecked box, here's code:

<fo:inline font-family="ZapfDingbats" font-size="10pt">❏</fo:inline>

For the cheked box, here's my solution:

<fo:inline font-family="ZapfDingbats" font-size="6pt" border="1pt black solid">✕</fo:inline>

Try to use "X" plus the border to create the checked box.

RedHat Linux JDK1.6 and Tomcat 1.6 installation

2009-05-11T12:49:00.000-07:00

The current java on wwwp path is: /usr/lib/jvm/jre-1.6.0-sun.x86_64/bin/java
We need the Java JDK instead of Jre.

Downloaded current JDK 1.6 from Sun web site: jdk-6u13-linux-x64-rpm.bin
> cp -p /tmp/jdk-6u13-linux-x64-rpm.bin /var/www/.

> chmod a+x /var/www/jdk-6u13-linux-x64-rpm.bin
> ./jdk-6u13-linux-x64-rpm.bin
> /usr/sbin/alternatives --install /usr/bin/java java /usr/java/latest/bin/java 1
> /usr/sbin/alternatives --config java choose the java you wanted.

Package name is "jdk-1.6.0_13-fcs". To view the package info, use command:
>rpm -qc jdk

Download Tomcat 1.6 tar.gz
> tar -zxvf jakarta-tomcat-6.x.xx.tar.gz

Create a symbolic link to a tomcat directory:
> ln -s apache-tomcat-6.0.26 tomcat

After install Tomcat, use another user account instead of root to run the Tomcat:
1. Add a group:
> /usr/sbin/groupadd other

2. See if the group is added:
> grep other /etc/group
If you see something like this, it is added, otherwise do it again:
> other:x:1000000:

3. List users:
> cat /etc/passwd

LAMP on Mac

2008-12-04T12:59:00.000-08:00

Apache config file:
> /etc/apache2/httpd.conf

To add php support to Apache, uncomment this line in httpd.conf:
#loadModule php5_module libexec/apache2/libphp5.so
Remove the "#" from the line, then save.
If you can not save because the file is read only, try to use sudo to open the file:
> sudo vi httpd.conf

Then restart Apache server on Mac:
> sudo /usr/sbin/apachectl restart

If you want to become root on terminal, When logged in as an user with Admin privilege, open the Terminal application and give the command:
> sudo tcsh