How to Connect to MySQL in JSP

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We use tomcat as the container used for instructions in the post. 1) Download the driver mysql-connector-java-*.*.*-bin.jar and put it into WEB-INF/lib/, and remember to restart tomcat. 2) The example code as follows. String driverName=”com.mysql.jdbc.Driver”; String userName=”username”; String userPasswd=”password”; String dbName=”dbname”; String tableName=”tablename”; String url=”jdbc:mysql://localhost/”+dbName+”?user=”+userName+”&password=”+userPasswd; Class.forName(“com.mysql.jdbc.Driver”).newInstance(); Connection conn=DriverManager.getConnection(url); Statement statement = conn.createStatement(); String sql=”SELECT *
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Controlling Display of WordPress Widget with PHP Code

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I am always wondering how to display different Widgets in WordPress depending on the page/post/category etc. I ever tried some plugins that is for specific purpose. However, they are not flexible enough for all my needs. For example, I want a widget that contains AdSense ad not display on certain posts that I selected and
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Google PageRank Update 2011

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Update 3: Fclose.com sees minor PageRank updates on November 8, 2011. For example, some tooles and some posts get PageRank of 3 from 0. Update: Confirmed that Google updates the PageRank in toolbar on November 8 2011. Update 2: Google updates the PageRank in toolbar on August 05 2011. Update 1: Google updates the PageRank
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How to Redirect WordPress Feed to Feedburner Using .htaccess

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.htaccess is a powerful tool. Let’s look at how to using .htaccess to redirect WordPress feeds to feedburner. Let’s use my blog as the example. The WordPress’s feed url of my blog is https://www.systutorials.com/feed/. Now I want to redirect it to feedburner with url http://feeds.feedburner.com/systutorials . The idea is quite straightforward: For every request to
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Script: Checking Alive Servers from a Server List

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With a list of servers, it is common that one or more are down or crash. Lots cluster management tools can detect the aliveness of servers. However, it can be easily done with ping with a Bash script. I summarize the script that I used and share it here: check-alive-server.sh. Usage: usage: ./check-alive-server.sh file Each
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Script: Shutting Down All Xen VMs on a Server

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Shutting down servers is a common operations for managing a cluster. However, if this server is configured to a Xen Dom0 and has Xen VMs (DomUs), the VMs should be shutdown first to avoid data lost on these VMs. xm supports a -a option to shutdown all VMs: # xm shutdown -a Add the -w
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Emacs Tips and Howtos

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With Emacs, I feel happy. I love the rich functions of Emacs, such as compiling, quickly jumping to the lines with compilation error and debugging with gdb, and more. I ever wrote small tips posts about Emacs before. But it is a good idea to put them together and keep adding new ones. Here comes
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How to Generate and Apply Patches using diff and patch on Linux

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`diff` and `patch` are tools to create patches and apply patches to source code, which is widely used in the open-source world, such as Linux kernel and application. patch: applying patches To apply a patch to a single file: $ patch < foo.patch If the foo.patch does not identify the file the patch should be
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Setting MATE as Default Desktop Environment for startx on Fedora

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I ever discussed Starting KDE from Command Line by startx for KDE and GNOME. Recently, I installed MATE desktop on Fedora 17 and am very happy with it—dear, Gnome 2 is back. However, I checked the /etc/X11/xinit/Xclients script which is called by ‘startx’ and it only includes ‘startkde’ and ‘gnome-session’ without support to MATE. But
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How to Install MS Office 2007 on Linux using Wine

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As a Linux user, I must keep a copy of Windows. One reason is that I should edit MS Office files, such as .doc, .ppt, .xls and .xml (office 2003 xml format) required by, created by or for other using Windows. Wine worked for me with Office 2003 ever but has this or that problem.
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Online Tutorials for Linux Beginners

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This post compiles a list of tutorials on the Internet for Linux beginners. Linux beginners usually get headache from the “seemed” complexity of the Linux operation system. But once they get into the gate and get familiar with Linux, they will love it. UNIX Tutorial for Beginners “A beginners guide to the Unix and Linux
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Vim as KMail’s External Editor

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Vim is my favourite text editor and I also prefer to use Vim to compose Email. I ever used Vim as Thunderbird’s External editor with the help of plugin. I started to use KMail as my email client on KDE and I find it is not hard to configure KMail to use Vim as email
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How to Upgrade Fedora to Newer Version with Yum

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The latest tools for upgrading Fedora is FedUp, please check How to upgrade Fedora 19 to Fedora 20 through the network. Please consider PreUpgrade for upgrading Fedora. This is the recommended method. This post makes a list of actions should be done to upgrade Fedora using yum. Please note that this is for experienced users
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Setting Up Ubuntu DomU on Xen: Ubuntu 10.10 on Fedora Xen Dom0

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Setting up Ubuntu 10.10 DomU on top of Fedora Xen Dom0 is introduced in this post. The process of setting up Ubuntu 10.10 DomU is the same as Setting Up Stable Xen DomU with Fedora: Unmodified Fedora 12 on top of Xenified Fedora 12 Dom0 with Xen 4.0 This post only show the difference which
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How to Revert Changes in Git

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We make mistakes when developing before or after committing in git. We may revert changes and fix our mistake by using git. Revert entire working tree before committing We can return the entire working tree to the last committed state if we mess up the working tree: $ git reset –hard HEAD Revert changes to
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Duplicating LVM Backed Xen DomU

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LVM’s snapshot feature enables us to duplicate an LVM backed Xen DomU in seconds rather than minutes. We no longer need to copy the entire file system image like backing up file backed Xen DomU. We just need to make a snapshot of the current Xen DomU in seconds. When there are changes to the
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Setting Up Xen DomU on Fedora Linux (Fedora 12)

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Creating file-backed virtual block device (VBD) for Xen virtual machines and installing Fedora 12 in Xen DomU via internet will be introduced. Note that this tutorial is based on a pretty old OS (Fedora 12). But the method here is still valid while some minor details may need to be changed for latest Xen and
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How to Start KDE from Command Line using startx

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I don’t use xdm, gdm or kdm… I prefer my Linux booting to init 3. I like logging in to the command-prompt and starting X manually with startx. In my Fedora Linux box, I always get to gnome even both gnome and KDE are installed. Actually the startx script is already written for most of
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