1、拷贝Other\FirefoxPortableSource\FirefoxPortable.ini到根目录，跟firefoxportable.exe同一个目录

2、修改AllowMultipleInstances=true

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把max_statements设置为0。
c3p0在同时关闭statement和connection的时候，或者关闭他们之间的时间很短的时候，有时候connection并没有被关闭，因为有些preparedstatement还在被cached住。这是c3p0的作者自己说的。
http://forum.hibernate.org/viewtopic.php?t=947246&highlight=apparent+deadlock+c3p0

C3P0增加以下配置信息:

A c3p0 pool with the settings you have should recover from a database reset, but that doesn't mean you will never see an Exception. Stale Connections from the old database session will still be broken, and if those Connections have already been checked out, or if they are in the pool and not tested on checkout, the application will see the broken Connection, in the form of an Exception.

You can use c3p0 to minimize the likelihood that your application will see a stale Connection on database shutdown/restart. The most reliable means of preventing this is to set hibernate.c3p0.validate to true (in a hibernate application -- all other c3p0 apps should use the c3p0-native property c3p0.testConnectionOnCheckout). If you set this property to true, c3p0 will test Connections prior to checkout, and your app will never see a stale Connection on database restart unless the Connection had already been checked out when the database went down.

Another less reliable, but potentially less expensive, strategy is to set c3p0.testConnectionsOnCheckin and hibernate.c3p0.idle_test_period (c3p0-native c3p0.idleConnectionTestPeriod) to a low value, in which case all connection tests are asynchronous and you are guanteed that no Connection will be checked out that hasn't been tested in the last idle_test_period seconds. Thus, your app will only see broken Connections from the pool if Connections are checked out during a short window of time.

In either case, I recommend setting "c3p0.preferredTestQuery" or "c3p0.automaticTestTable" in your c3p0 properties file, as c3p0's default Connection test is often slow.

See "Configuring Connection Testing" in c3p0's docs for more information.

在使用c3p0作为连接池时，其中的一些配置参数需要修改。主要是maxIdleTime和idleConnectionTestPeriod。 MySQL默认是8小时（28800秒）后自动关闭已打开的连接，所以c3p0要在8小时内关闭不使用的连接，上面的2参数要小于28800秒。附上在 hibernate中配置c3p0的关键字。

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When you need to edit a configuration file from the command line in a pinch, use these tips for the ins and (especially) outs of vim.

If one thing is for sure about Linux, it's that it has no shortage of text editors. This reflects the largely text-based nature of Linux, from the command line, to the source code, to the configuration files that programs refer to. When you are in a desktop environment, you can use one of many graphical tools to edit text files; however, in an emergency situation, or when logged into a machine remotely, you may need to fall back on a command-line text editor. Under Ubuntu, the default text editor is vim, and this hack provides you with the basic information you need to make changes to configuration files using vim.

The vi editor has a rather mixed reputation. Some people love how quickly you can edit files with it, and others hate its steep learning curve. The vim editor (short for "Vi IMproved") takes vi and adds not only a number of powerful improvements, but also a number of user-friendly changes such as a complete, integrated help environment. Ubuntu includes vim by default, and even if you run vi, you are actually running vim in a vi-like emulation mode.

So, to edit a file, run vim on the command line followed by the filename as an argument. For instance, to edit the filesystem table (/etc/fstab), type:

$ sudo vim /etc/fstab
         

Unlike most other editors you may be used to, vim operates via a number of modes. Different keys perform different functions depending on which mode you are in. (This can be rather confusing the first time you use vim, since you will start typing only to see all sorts of strange and undesirable behavior.) For starters, there are two main modes you will be operating in: Normal mode (for navigating the file) and Insert mode (for editing text).

Navigate Through the File

Normal mode is the main mode you default to when you start vim. In this mode, you use a number of different keys to move through the file. Table 8-1 lists some of the main navigation keys and their functions.

Table VIM Normal Mode keybindings

Navigation key	nction
h, j, k, l	Move left, up, down, or right, respectively. The arrow keys will also move the cursor.
w, b	Move forward or backword one word at a time, respectively. Useful when you want to skip through a file quickly.
^, $	Move to the beginning or the end of the current line, respectively.
gg, G	Move to the beginning or the end of the file, respectively.
: number	Move to the specified line number in the file.
/ keyword	Search for the specified keyword; hit n to move to the next keyword.

Edit a Line

Once you have moved to where you wish to edit, you have a number of different options to edit a line. If you simply need to delete some text, the x key will delete the character under the current cursor. To add or change text, you will need to switch to Insert mode. Once in Insert mode, vim behaves a lot like other text editors; when you type a particular key, it will appear in the file. There are a number of ways to get into Insert mode, depending on where you want to start editing, but the simplest is to hit i, which will let you edit at the current position of the cursor.

Once in Insert mode, you can make any changes you need to a particular file. You can hit the Backspace or Delete key to delete characters and can still use the arrow keys to move around in the file. Once you are finished, hit the Esc key to exit Insert mode.

Copy and Paste

Sometimes when editing a file it is useful to copy and paste one line or a section of a line to another line. There are a number of ways to do so, some faster than others, but for new vim users, one of the easiest ways is through vim's Visual mode. To select a portion of text, type Esc until you are in Normal mode, move to the beginning of the text you want to copy, and then hit the v key to switch to Visual mode. Now move the cursor as normal, and you will notice that characters will be selected as it moves. When you have selected all of the characters you want, hit the y key to copy (or yank) the text. Then move to where you want to paste it and hit p.

If you know you want to copy full lines at a time, enter Visual mode with capital V instead of v. Now move up or down to select a number of lines and type y to copy and then p to paste your lines.

Undo

Once nice feature that vim has that vi doesn't is unlimited undos. If you make a mistake and want to undo it, hit Esc until you are in Normal mode, and then simply type the u key to step back through each edit. If you find you need to redo a change, type Ctrl-R.

Save and Exit

After you have made your changes and are ready to save, you need to switch to Command mode. Command mode lets you run special vim commands, including the commands you need to save changes and exit. To save (or write) your changes, type :w and press Enter. When you are ready to quit, type :q and press Enter. You can also combine these two commands into a single command, and type :wq and press Enter.

Search and Replace

A common need when editing files is to substitute one word for another throughout the file. To do so in vim, type:

:s/word/replacement/g

to change all instances of the word on a particular line. To change all instances of the word within a file, type:

:%s/word/replacement/g

If you want to give confirmation before making each change, add a c to the end of the command:

:%s/word/replacement/gc

and vim will ask you before it makes any changes.

One particularly handy use of the search-and-replace feature when editing configuration files is for commenting or uncommenting multiple lines in the file. To do so, enter Visual mode, select each line you want to comment, and then type:

:s/^/#/

to comment the lines out with the # character. Replace # with whatever character that file uses for comments. If you instead want to uncomment a number of lines, select them in Visual mode and then type:

:s/^#//

or replace # with the character your file uses for comments.

Help

If you find you are lost, or you just want some help with vim's options, type:

:help

to enter vim's help screen. You can also follow :help with a particular keyword, so if you want to find out what the w key does, for instance, type:

:help w

Where to Learn More

This hack is by no means an exhaustive tutorial on how to use vim. vim has a number of advanced and powerful features that, once learned, allow you to make rapid changes to files. If you want to know more about vim's features and how to use them, type:

$ vimtutor
            

at the command line to try vim's built-in interactive tutorial program.

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1，简单替换表达式

替换命令可以在全文中用一个单词替换另一个单词：

:%s/four/4/g

“%” 范围前缀表示在所有行中执行替换。最后的 “g” 标记表示替换行中的所有匹配点。如果仅仅对当前行进行操作，那么只要去掉%即可

如果你有一个象 “thirtyfour” 这样的单词，上面的命令会出错。这种情况下，这个单词会被替换成”thirty4″。要解决这个问题，用 “\<” 来指定匹配单词开头：

:%s/\

显然，这样在处理 “fourty” 的时候还是会出错。用 “\>” 来解决这个问题：

:%s/\

如果你在编码，你可能只想替换注释中的 “four”，而保留代码中的。由于这很难指定，可以在替换命令中加一个 “c” 标记，这样，Vim 会在每次替换前提示你：

:%s/\

2，删除多余的空格

要删除这些每行后面多余的空格，可以执行如下命令：

:%s/\s\+$//

命令前面指明范围是 “%”，所以这会作用于整个文件。”substitute” 命令的匹配模式是

“\s\+$”。这表示行末（$）前的一个或者多个（\+）空格（\s）。替换命令的 “to” 部分是空的：”//”。这样就会删除那些匹配的空白字符。

3，匹配重复性模式

星号项 “*” 规定在它前面的项可以重复任意次。因此:

/a*

匹配 “a”，”aa”，”aaa”，等等。但也匹配 “” (空字串)，因为零次也包含在内。星号 “*” 仅仅应用于那个紧邻在它前面的项。因此 “ab*” 匹配 “a”，”ab”，”abb”,”abbb”，等等。如要多次重复整个字符串，那么该字符串必须被组成一个项。组成一项的方法就是在它前面加 “\(”，后面加 “\)”。因此这个命令:

/\(ab\)*

匹配: “ab”，”abab”，”ababab”，等等。而且也匹配 “”。

要避免匹配空字串，使用 “\+”。这表示前面一项可以被匹配一次或多次。

/ab\+

匹配 “ab”，”abb”，”abbb”，等等。它不匹配 后面没有跟随 “b” 的 “a”。

要匹配一个可选项，用 “\=”。 例如:

/folders\=

匹配 “folder” 和 “folders”。

4，指定重复次数

要匹配某一项的特定次数重复，使用 “\{n,m}” 这样的形式。其中 “n” 和 “m” 都是数字。在它前面的那个项将被重复 “n” 到 “m” 次 (|inclusive| 包含 “n” 和 “m”)。例如:

/ab\{3,5}

匹配 “abbb”，”abbbb” 以及 “abbbbb”。

当 “n” 省略时，被默认为零。当 “m” 省略时，被默认为无限大。当 “,m” 省略时，就表示重复正好 “n” 次。例如:

模式 匹配次数

\{,4} 0，1，2，3 或 4

\{3,} 3，4，5，等等

\{0,1} 0 或 1，同 \=

\{0,} 0 或 更多，同 *

\{1,} 1 或 更多，同 \+

\{3} 3

5，多选一匹配

在一个查找模式中，”或” 运算符是 “\|”。例如:

/foo\|bar

这个命令匹配了 “foo” 或 “bar”。更多的抉择可以连在后面:

/one\|two\|three

匹配 “one”，”two” 或 “three”。

如要匹配其多次重复，那么整个抉择结构须置于 “\(” 和 “\)” 之间:

/\(foo\|bar\)\+

这个命令匹配 “foo”，”foobar”，”foofoo”，”barfoobar”，等等。

再举个例子:

/end\(if\|while\|for\)

这个命令匹配 “endif”，”endwhile” 和 “endfor”。

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If you are running Ubuntu on a computer with a Windows disk, you may want to read and write to the disk. Ubuntu can safely read the Windows NT NTFS partitions and can read and write to Windows 95/98/2000 FAT32 partitions.

First, load a terminal, and use the fdisk command to know what partitions you currently have:

foo@bar:~$ sudo fdisk -l

The output should be similar to this:

Disk /dev/hda: 81.9 GB
Device Boot      Start    End       Blocks      Id     System
/dev/hda1 *          1    1306    10490413+      7     HPFS/NTFS
/dev/hda2         1307    1311       40162+     83     Linux
/dev/hda3         1312    1344      265072+     82     Linux swap
/dev/hda4         1345    9964    69240150       f     W95 Ext'd (LBA)
/dev/hda5         1345    1606     2104483+      b     W95 FAT32
/dev/hda6         1607    2852    10008463+     83     Linux
...

In this output, the /dev/hda1 partition (the first partition on the first disk) is a 10GB Windows NTFS partition (probably called C:) and /dev/hda5 is a 2GB FAT32 partition (probably called D:).

When you access a disk, you need to mount it first. To mount it, you need to indicate a directory where the files from the disk are accessedthis is called a mount point. Create mount points in /media for the Windows partitions. It is good to use /media/C for C: and /media/D for D:, etc. to make things easy to remember.

foo@bar:~$ sudo mkdir /media/C /media/D

To make the disks accessible when you boot the computer, you need to add a few lines to /etc/fstab. This file indicates which disks are available. Add the following two lines:

/dev/hda1     /media/C     ntfs     nls=utf8,umask=0222    0     0
/dev/hda5     /media/D     vfat     defaults,umask=0000    0     0

The fourth column lets you specify options for mounting the partition, and nls=utf8,umask=0222 means that any user can read the NTFS partition.

To mount the two partitions without restarting, run the following command:

foo@bar:~$ sudo mount -a

The two partitions are now available and will be automatically mounted the next time Ubuntu is restarted.

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If you try to install some software or upgrade your computer, and you get an error, the package manager may have tied itself in a knot. To try to resolve this, open a terminal, and run the following commands:

foo@bar:~$ sudo apt-get update
foo@bar:~$ sudo apt-get -f install

The first command updates your package list, and the second command tries to fix your package manager. If this is successful the packages that failed will be installed correctly.

In addition to these commands, you can reconfigure any packages that have not yet been configured by running:

foo@bar:~$ sudo dpkg configure pending

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In the rare situation that the desktop hangs, first try to restart it by pressing Alt-Ctrl-Backspace at the same time. This kills and restarts the X server. Another method of killing the X server is to press Alt+F2 to jump to a terminal, log in, and then run this command:

foo@bar:~$ /etc/init.d/gdm stop

This command stops the graphical login screen, which in turn stops the X server. You can restart it with this command:

foo@bar:~$ /etc/init.d/gdm start

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When a distribution package is not available, the source code is always available to compile with Open Source applications. Compilation is the process of converting programming code into a program that you can run and use. Although it sounds like a devilishly difficult process, it is typically fairly simple.

You should first have a look on the application's Web page, or in the INSTALL or README file that is included with the code to see what software the application needs to run. When you know what is required, use Synaptic to search for the required tools. Many of the requirements will be software libraries (software that applications require to run), and these libraries typically have "lib" at the start of the package name. As an example, if you need to have the Vorbis audio codec installed, do a search in Synaptic for Vorbis, and libvorbis will be one of the packages. You should also install with -dev at the end of the package name (such as libvorbis-dev). These packages allow you to compile software for that library.

The process of compiling software involves three steps: (1) configuration, (2) compilation, and (3) installation. Open a terminal, move into the directory from which you extracted the source code, and configure it:

foo@bar:yourapp$ ./configure

When you run ./configure, it checks to see that you have all the required software. If it throws an error, it is likely that a required tool or library is missing. Find out what it is, and install it. Typically, configure will tell you what you need to install.

If the configure script works fine, compile the code with this command:

foo@bar:yourapp$ make

If a problem appears when compiling the software, it may be a bug or problem in the source code. It is best to refer your problem to the author of the code for further help.

If the compile process was successful, install the application with this command:

foo@bar:yourapp$ sudo make install

The software is now fully installed.

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Open a terminal, and then go to the folder where the ISO image has been downloaded. As an example, if you saved it to your disk in Firefox, it will have saved it to the Desktop folder in your home folder:

foo@bar:~$ cd Desktop

To test that the ISO image works, you are going to mount it and access the files in a particular folder. First, create this folder:

foo@bar:~$ mkdir test_iso

Now mount it on that folder:

foo@bar:~$ sudo mount -o loop -t iso9660 my_iso_file.iso test_iso

That's it! Now you can browse the folder test_iso.

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