c++ difference from java
1. take charge of object management , negotiate ownershiop ,use scoped_ptr,
   not to transfer other's ownership
2. use c++ template to express seperation corncern ,such as (static)polymorphy and policy
3. disable copy constructor and assign operator by yourself
4. polymorphy by pointer
5. 使用 template ,macro 取得类似动态语言的能力
6. 偏好无状态的 函数

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Myisam is preferred without transaction and little update(delete)

Big than 4G datafile can user Myisam merge table.

InnoDB with auto_increment primary key is preferred.

Few storage process

Guess: 20m records max per table , 500G data max per tablespace , 256 tables per database (may problem)

Use prepared statement and  batch

Optimize Your Queries For the Query Cache

// query cache does NOT work

$r = mysql_query("SELECT username FROM user WHERE signup_date >= CURDATE()");

// query cache works!

$today = date("Y-m-d");

$r = mysql_query("SELECT username FROM user WHERE signup_date >= '$today'");

EXPLAIN Your SELECT Queries

LIMIT 1 When Getting a Unique Row

Index and Use Same Column Types for Joins

Do Not ORDER BY RAND()

Avoid SELECT *

t is a good habit to always specify which columns you need when you are doing your SELECT’s.

Use ENUM over VARCHAR

Use NOT NULL If You Can

Store IP Addresses as UNSIGNED INT (?)

Fixed-length (Static) Tables are Faster

Vertical Partitioning

Vertical Partitioning is the act of splitting your table structure in a vertical manner for optimization reasons.

Example 1: You might have a users table that contains home addresses, that do not get read often. You can choose to split your table and store the address info on a separate table. This way your main users table will shrink in size. As you know, smaller tables perform faster.

Example 2: You have a “last_login” field in your table. It updates every time a user logs in to the website. But every update on a table causes the query cache for that table to be flushed. You can put that field into another table to keep updates to your users table to a minimum.

But you also need to make sure you don’t constantly need to join these 2 tables after the partitioning or you might actually suffer performance decline.

Split the Big DELETE or INSERT Queries

If you have some kind of maintenance script that needs to delete large numbers of rows, just use the LIMIT clause to do it in smaller batches to avoid this congestion.

Smaller Columns Are Faster

Use an Object Relational Mapper

f you do not need the time component, use DATE instead of DATETIME.

Consider horizontally spitting many-columned tables if they contain a lot of NULLs or rarely used columns.

Be an SQL programmer who thinks in sets, not procedural programming paradigms

InnoDB can’t optimize SELECT COUNT(*) queries. Use counter tables! That’s how to scale InnoDB.

Prefer MM with hive

refer :

http://blog.tuvinh.com/top-20-mysql-best-practices/

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从时序图中可以看到，createNewIO()就是新建了一个com.mysql.jdbc.MysqlIO，利用 com.mysql.jdbc.StandardSocketFactory来创建一个socket。然后就由这个mySqlIO来与MySql服务器进行握手(doHandshake())，这个doHandshake主要用来初始化与Mysql server的连接，负责登陆服务器和处理连接错误。在其中会分析所连接的mysql server的版本，根据不同的版本以及是否使用SSL加密数据都有不同的处理方式，并把要传输给数据库server的数据都放在一个叫做packet的 buffer中，调用send()方法往outputStream中写入要发送的数据。


useServerPreparedStmts置为true的话，mysql驱动可以通过PreparedStatement的子类ServerPreparedStatement来实现真正的PreparedStatement的功能




第一位表示数据包的开始位置，就是数据存放的起始位置，一般都设置为0，就是从第一个位置开始。第二和第三个字节标识了这个数据包的大小，注意的是，这个大小是出去标识的4个字节的大小，对于非最后一个数据包来说，这个大小都是一样的，就是splitSize，也就是maxThreeBytes，它的值是 255 * 255 * 255。
最后一个字节中存放的就是数据包的编号了，从0开始递增。
在标识位设置完毕之后，就可以把255 * 255 * 255大小的数据从我们准备好的待发送数据包中copy出来了，注意，前4位已经是标识位了，所以应该从第五个位置开始copy数据

 # packetToSend = compressPacket(headerPacket, HEADER_LENGTH,    
#                 splitSize, HEADER_LENGTH); 

LoadBalancingConnectionProxy
package java.lang.reflect 。 proxy .


http://developer.51cto.com/art/200907/137823.htm

http://dev.mysql.com/doc/refman/5.1/en/connector-j-reference-implementation-notes.html

PreparedStatements are implemented by the driver, as MySQL does not have a prepared statement feature. Because of this, the driver does not implement getParameterMetaData() or getMetaData() as it would require the driver to have a complete SQL parser in the client.

Starting with version 3.1.0 MySQL Connector/J, server-side prepared statements and binary-encoded result sets are used when the server supports them.

但这是不是说PreparedStatement没用呢？不是的，PreparedStatement有其他的好处：
1.代码的可读性和可维护性
2.最重要的一点是极大地提高了安全性，可以防止SQL注入

然后我又看了一些网上其他人的经验，基本和我的判断一致，有两点要特别提请大家注意：

1.并不是说PreparedStatement在所有的DB上都不会提高效率，PreparedStatement需要服务器端的支持，比如在 Oracle上就会有显著效果。上面说的测试都是在MySQL上测试的，我找到了一个MySQL架构师的帖子，比较明确地说明了MySQL不支持 PreparedStatement。

2.即便PreparedStatement不能提高性能，在少数使用时甚至会降低效率，但仍然应该使用PreparedStatement！因为其他好 处实在是太大了！当然，当SQL查询比较复杂时，可能PreparedStatement好处会更大，只是我没有测试，不敢肯定。

3.既然PreparedStatement不能提高效率，那PreparedStatement Pool也就没有必要了。但可以看到每次新建Connection的开销实在很大，因此Connection Pool绝对必要。

download ,annatation and tools 两个项目。
添加相关的 jar.

<taskdef name="hibernatetool" classname="org.hibernate.tool.ant.HibernateToolTask" classpathref="master.classpath" />

<target name="create_table">

<hibernatetool destdir="${script.dir}">
    <annotationconfiguration configurationfile="src/hibernate.cfg.xml" />
    <hbm2ddl export="false" create="true" delimiter=";" format="true" outputfilename="create-tables.sql" />
</hibernatetool>

</target>

<!DOCTYPE hibernate-configuration PUBLIC
    "-//Hibernate/Hibernate Configuration DTD 3.0//EN"
    "http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd">

<hibernate-configuration>
    <session-factory name="logi">
        <property name="show_sql">true</property>
        <mapping class="com.tt.logi.target.Target"/>
   
    </session-factory>
</hibernate-configuration>

import java.io.Serializable;

import javax.persistence.Basic;
import javax.persistence.Entity;
import javax.persistence.Id;

@Entity
public class Target implements Serializable{
   
    private Long id;
    private String name;
    @Id
    public Long getId() {
        return id;
    }
    public void setId(Long id) {
        this.id = id;
    }
    @Basic
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
   
   
   

wget ftp://ftp.jaist.ac.jp/pub/mysql/Downloads/MySQL-5.1/mysql-5.1.41.tar.gz
tar -xzf



./configure --prefix=/usr/local/mysql51m --without-debug  --enable-local-infile --enable-assembler --enable-thread-safe-client --with-plugins=all

make
su -
make install


groupadd mysql
useradd -g mysql mysql


bin/mysql_install_db --user=mysql  --datadir=/var/lib/mysql51m/data

chown -R mysql /var/lib/mysql51m/
chgrp -R mysql /var/lib/mysql51m/


cp share/mysql/my-innodb-heavy-4G.cnf my.cnf
vi my.cnf

datadir = /var/lib/mysql51m/data

.bin/mysqld_safe --defaults-file=/usr/local/mysql51m/my.cnf &

bin/mysql  --defaults-file=my.cnf -uroot

./mysqladmin -u root password ‘humber’
grant all on *.* to root@% identified by 'humber'

default-character-set=utf8
init_connect='SET NAMES utf8'
default-storage-engine = INNODB

jmap -heap 16761
jstat -gcutil 16761
jmap -finalizerinfo 16761
jmap -histo 16761
jstack -l 16761
jinfo 16761

Examine the fatal error log file. Default file name is hs_err_pidpid.log in the working-directory.

-XX:+HeapDumpOnOutOfMemoryError
java -agentlib:hprof=heap=dump,format=b application
$ jmap -dump:format=b,file=snapshot.jmap process-pid

1、在jvm启动时加上：-agentlib:hprof=heap=sites,file=heap.txt  ，然后执行一段时间后执行 kill -3 <pid>，就可以获取jvm的内存镜像。类似的通过-agentlib:hprof=cpu=samples,file=cpu.txt查 看cpu的状况。

http://java.sun.com/javase/6/webnotes/trouble/other/matrix6-Unix.html

Quick Troubleshooting Tips on Solaris OS and Linux for Java SE 6

This "Quick Start Guide" gives you some quick tips for troubleshooting. The subsections list some typical functions that can help you in troubleshooting, including one or more ways to get the information or perform the action.

These tips are organized as follows:

Hung, Deadlocked, or Looping Process
Post-mortem Diagnostics, Memory Leaks
Monitoring
Actions on a Remote Debug Server
Other Functions

Hung, Deadlocked, or Looping Process

• Print thread stack for all Java threads:
  • Control-"
  • kill -QUIT pid
  • jstack pid (or jstack -F pid if jstack pid does not respond)
• Detect deadlocks:
  • Request deadlock detection: JConsole tool, Threads tab
  • Print information on deadlocked threads: Control-"
  • Print list of concurrent locks owned by each thread: -XX:+PrintConcurrentLocks set, then Control-"
  • Print lock information for a process: jstack -l pid
• Get a heap histogram for a process:
  • Start Java process with -XX:+PrintClassHistogram, then Control-"
  • jmap -histo pid (with -F option if pid does not respond)
• Dump Java heap for a process in binary format to file:
  • jmap -dump:format=b,file=filename pid (with -F option if pid does not respond)
• Print shared object mappings for a process:
  • jmap pid
• Print heap summary for a process:
  • Control-"
  • jmap -heap pid
• Print finalization information for a process:
  • jmap -finalizerinfo pid
• Attach the command-line debugger to a process:
  • jdb -connect sun.jvm.hotspot.jdi.SAPIDAttachingConnector:pid=pid

Post-mortem Diagnostics, Memory Leaks

• Examine the fatal error log file. Default file name is hs_err_pidpid.log in the working-directory.
• Create a heap dump:
  • Start the application with HPROF enabled: java -agentlib:hprof=file=file,format=b application; then Control-"
  • Start the application with HPROF enabled: java -agentlib:hprof=heap=dump application
  • JConsole tool, MBeans tab
  • Start VM with -XX:+HeapDumpOnOutOfMemoryError; if OutOfMemoryError is thrown, VM generates a heap dump.
• Browse Java heap dump:
  • jhat heap-dump-file
• Dump Java heap from core file in binary format to a file:
  • jmap -dump:format=b,file=filename corefile
• Get a heap histogram for a process:
  • Start Java process with -XX:+PrintClassHistogram, then Control-"
  • jmap -histo pid (with -F option if pid does not respond)
• Get a heap histogram from a core file:
  • jmap -histo corefile
• Print shared object mappings from a core file:
  • jmap corefile
• Print heap summary from a core file:
  • jmap -heap corefile
• Print finalization information from a core file:
  • jmap -finalizerinfo corefile
• Print Java configuration information from a core file:
  • jinfo corefile
• Print thread trace from a core file:
  • jstack corefile
• Print lock information from a core file:
  • jstack -l corefile
• Attach the command-line debugger to a core file on the same machine:
  • jdb -connect sun.jvm.hotspot.jdi.SACoreAttachingConnector:javaExecutable=path,core=corefile
• Attach the command-line debugger to a core file on a different machine:
  • On the machine with the core file: jsadebugd path corefile
    and on the machine with the debugger: jdb -connect sun.jvm.hotspot.jdi.SADebugServerAttachingConnector:debugServerName=machine
• libumem can be used to debug memory leaks.

Monitoring

Note: The vmID argument for the jstat command is the virtual machine identifier. See the jstat man page for a detailed explanation.

• Print statistics on the class loader:
  • jstat -class vmID
• Print statistics on the compiler:
  • Compiler behavior: jstat -compiler vmID
  • Compilation method statistics: jstat -printcompilation vmID
• Print statistics on garbage collection:
  • Summary of statistics: jstat -gcutil vmID
  • Summary of statistics, with causes: jstat -gccause vmID
  • Behavior of the gc heap: jstat -gc vmID
  • Capacities of all the generations: jstat -gccapacity vmID
  • Behavior of the new generation: jstat -gcnew vmID
  • Capacity of the new generation: jstat -gcnewcapacity vmID
  • Behavior of the old and permanent generations: jstat -gcold vmID
  • Capacity of the old generation: jstat -gcoldcapacity vmID
  • Capacity of the permanent generation: jstat -gcpermcapacity vmID
• Monitor objects awaiting finalization:
  • JConsole tool, VM Summary tab
  • jmap -finalizerinfo pid
  • getObjectPendingFinalizationCount method in java.lang.management.MemoryMXBean class
• Monitor memory:
  • Heap allocation profiles via HPROF: java -agentlib:hprof=heap=sites
  • JConsole tool, Memory tab
  • Control-" prints generation information.
• Monitor CPU usage:
  • By thread stack: java -agentlib:hprof=cpu=samples application
  • By method: java -agentlib:hprof=cpu=times application
  • JConsole tool, Overview and VM Summary tabs
• Monitor thread activity:
  • JConsole tool, Threads tab
• Monitor class activity:
  • JConsole tool, Classes tab

Actions on a Remote Debug Server

First, attach the debug daemon jsadebugd, then execute the command:

• Dump Java heap in binary format to a file: jmap -dump:format=b,file=filename hostID
• Print shared object mappings: jmap hostID
• Print heap summary : jmap -heap hostID
• Print finalization information : jmap -finalizerinfo hostID
• Print lock information : jstack -l hostID
• Print thread trace : jstack hostID
• Print Java configuration information: jinfo hostID

Other Functions

• Interface with the instrumented Java virtual machines:
  • Monitor for the creation and termination of instrumented VMs: jstatd daemon
  • List the instrumented VMs: jps
  • Provide interface between remote monitoring tools and local VMs: jstatd daemon
  • Request garbage collection: JConsole tool, Memory tab
• Print Java configuration information from a running process:
  • jinfo pid
• Dynamically set, unset, or change the value of certain Java VM flags for a process:
  • jinfo -flag flag
• Print command-line flags passed to the VM:
  • jinfo -flags
• Print Java system properties:
  • jinfo -sysprops
• Pass a Java VM flag to the virtual machine:
  • jconsole -Jflag ...
  • jhat -Jflag ...
  • jmap -Jflag ...
• Print statistics of permanent generation of Java heap, by class loader:
  • jmap -permstat
• Report on monitor contention.
  • java -agentlib:hprof=monitor=y application
• Evaluate or execute a script in interactive or batch mode:
  • jrunscript
• Interface dynamically with an MBean, via JConsole tool, MBean tab:
  • Show tree structure.
  • Set an attribute value.
  • Invoke an operation.
  • Subscribe to notification.
• Run interactive command-line debugger:
  • Launch a new VM for the class: jdb class
  • Attach debugger to a running VM: jdb -attach address
  http://www.blogjava.net/justinchen/archive/2009/01/08/248738.html

netstat -n | awk '/^tcp/ {++state[$NF]} END {for(key in state) print key,""t",state[key]}'

set nocompatible
set autoindent
set smartindent
set ignorecase
syntax enable
set wrap
set showmatch
set foldmarker={{{,}}}
set tabstop=4
set shiftwidth=4
set ruler
set expandtab
set backspace=eol,start,indent
set whichwrap+=<,>,h,l
set nobackup
setlocal noswapfile
set bufhidden=hide
syntax on
set tags=./tags,~/apsara/tags
set path+=/usr/include/c++/**,~/apsara/include/**
filetype plugin on
filetype indent on
autocmd filetype java,c,cpp setlocal textwidth=100
set pastetoggle=<F7>

nmap <F2>  :set nonumber!<CR>
nmap <F8>  :TlistToggle<CR>
imap <F11> <C-x><C-p>
map <F12>  :!ctags -R --c++-kinds=+p --fields=+iaS --exclude=build --extra=+q .<CR>
map <F6> :w<CR>
imap <F6> <ESC>:w<CR>a
map <F3> /<C-R><C-W><CR>

有 c support 支持，很棒。

1. 
   避免对shared_ptr所管理的对象的直接内存管理操作，以免造成该对象的重释放
   shared_ptr并不能对循环引用的对象内存自动管理（这点是其它各种引用计数管理内存方式的通病）。
2. 
   不要构造一个临时的shared_ptr作为函数的参数。
   如下列代码则可能导致内存泄漏：
   void test()
   {
       foo(boost::shared_ptr<implementation>(new    implementation()),g());
   }
   正确的用法为：
   void test()
   {
       boost::shared_ptr<implementation> sp    (new implementation());
       foo(sp,g());
   }

3. Employee boss("Morris, Melinda", 83000);

   Employee* s = &boss;

   This is usually not a good idea. As a rule of thumb, C++ pointers should only refer to objects allocated wth new.

copy:http://www.diybl.com/course/3_program/c++/cppjs/20090403/163770.html

抄录备忘：
其实没有.h也能很好的工作,但是当你发现一个外部链接的函数或外部变量,需要许多份

声明,因为c++这种语言,在使用函数和变量的时候,必须将他声明,为何要声明?声明之后才

知道他的规格,才能更好的发现不和规格的部分.你别妄想一个编译单元,会自动从另一个

编译单元那里得到什么信息,知道你是如何定义这个函数的.

    所以说,只要使用到该函数的单元,就必须写一份声明在那个.cpp里面,这样是不是很麻烦,

而且,如果要修改,就必须一个一个修改.这真让人受不了.

.h就是为了解决这个问题而诞生,他包含了这些公共的东西.然后所有需要使用该函数的.cpp,只需要

用#include包含进去便可.以后需要修改,也只是修改一份内容.

请注意不要滥用.h,.h里面不要写代码,.h不是.cpp的仓库,什么都塞到里面.

如果在里面写代码,当其他.cpp包含他的时候,就会出现重复定义的情况,

比如将函数func(){printf}；放到头文件a.h,里面还有一些a.cpp需要的声明等；

然后你发现b.cpp需要用到a.cpp里面的一个函数,就很高兴的将a.h包含进来.

注意,#include并不是什么申请指令,他就是将指定的文件的内容,原封不动的拷贝

进来.

这时候实际上a.cpp和b.cpp都有一个func()函数的定义.

如果这个函数是内部链接static的话,还好,浪费了一倍空间；

如果是extern,外部链接(这个是默认情况),那么根据在同一个程序内不可出现

同名函数的要求,连接器会毫不留情给你一个连接错误!

http://www.cnblogs.com/shelvenn/archive/2008/02/02/1062446.html

 一.    Perspective and Metaphor

Platform
Kernel
Framework

二.    Philosophy and discipline

Be aware of context
Extreme maintenance
Be pragmatic
Extreme abstract: Program to an interface (abstraction), not an implementation
  
Extreme separation of concerns
Extreme readability
Testability
No side effect
Do not repeat yourself

三.    Principle

DIP ，dependency inversion of control
OCP , open close
LSP , liskov substitute
ISP , interface segregation
SRP , single responsibility
LKP, Lease knowledge principle

四.    design pattern

Construction
Behavior
Structure

五.    anti-pattern、bad smell

Long method
Diverse change
    Repeated code
    Talk to stranger
    Pre optimize

六.    algorithms

 nLongN
 Divided and conqueror

 

七.    architecture

Hierarchal
Pipes and filter
Micro kernel
Broker
Black Board
    Interpreter

   
八.    Distributed & concurrent

What to concurrent

Scalability
    Stretch key dimensions to see what breaks

九.    languages

Ruby
Erlang
assemble
C
C++
Java
Python
Scala

Be ware of different program paradigms.

十.    Performance

 Minimize remote calls and other I/O
 Speed-up data conversion
 release resource as soon as possible 

十一.    architectures' future

软件设计思想的发展逻辑，大致是提高抽象程度 ，separation of concern 程度。
    fn(design )=  fn1(abstraction )+ fn2(separation of concern).

由于大规模数据处理时代的来临，下一代设计范式的重点：
1.    将是如何提高distributed(--concurrent) programing 的抽象程度 和 separation of concern 程度。
2.    dsl ，按照以上的公式，也确实是一个好的方向。

十二.    Reference

<art agile software development>
<prerefactor>
<design patterns>
<beautiful architecture>
<refactor>
<pattern oriented software architecture>
<extreme software development>
<beautiful code>
<patterns for parallel programming>
<java concurrent programming in practice>
<java performance tuning>
<the definite guide to hadoop>
<greenplum>
<DryadLINQ>
<software architecture in practice>
<97 things architecture should known>
http://en.wikipedia.org/wiki/Programming_paradigm

拷贝
mingliu.ttc  simsun.ttf  SURSONG.TTF  tahomabd.ttf  tahoma.ttf  verdanab.ttf  verdanai.ttf  verdana.ttf  verdanaz.ttf

 #mv simsun.ttc /usr/share/fonts/local/simsun.ttf
#cd /usr/share/fonts/local/
sudo mkfontscale
sudo mkfontdir

sudo fc-cache
cp fonts.scale fonts.dir
sudo chmod 755 *
sudo chkfontpath --add /usr/share/fonts/local/

#/etc/init.d/xfs restart
查检是否安装成功

fc-list |grep Sim

 NSimSun:style=Regular
SimSun:style=Regular
SimSun\-PUA:style=Regular

experience learned.

1. first think algorithm before concurrent
2. first solve top problem
3. memory can be problem with huge data processing
4.  not to use refletion frequently
5. prefering strategy that can optimize both cpu and memory .

technical
1. thread synchronizing is how to queuing
   be sure to use "while(!Thread.currentThread.isInterupted())

2. prefer high level  synchronizing facility to low level methodology such as await,notify

3. dedicated sorter is much faster


 

以前听过用友的牛人关于软件设计范型的时代划分，记得不太准确，不过基本上是业界公认的。
大致上是：过程式、面向对象、组件、面向服务。
未来呢？我忘记了，抑或是 dsl ？

我以往也没有自己的认识，不过，最近我有自己的看法

软件设计思想的发展逻辑，大致是提高抽象程度 ，seperation of concern 程度。
    fn(design )=  fn1(abstraction )+ fn2(seperation of concern).


由于大规模数据处理时代的来临，下一代设计范式的重点：

1. 将是如何提高concurrent programing 的抽象程度 和 seperation of concern 程度。
2. 至于dsl ，我研究不多，不过，按照以上的公式，也确实是一个好的方向。

对于英文词语的使用，是因为，我想更能表达我的意思，不至于误解。见谅。
欢迎批评指正！

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最近看的东西，备忘。
Dryad
DryadLinq
GreenPlum。

技术上看：
 Dryad 牛
 
商业上看，
  只有microsoft(Dryad),oracle (?),ibm (?)

  其他的cloud data engine 似乎难免被收购宿命，一如bea 。。。。etc .
  ?google (Sawzall) ？amazon
  ?hadoop ,pig

中国：
  ?友友系统
 

Saas business

一.    chain
    customer : operator :application :feature: platform .
   
二.    operator
三.    application
    office
    erp
    mall
    game
四.    feature

    search engine
    monitor system
    security
    dynamic language
    special db system
    special file system
五.    platform
    virtual computing resource system
    cloud file system
    cloud db system
    cloud os

六.    chance
    big fish or small fish should find their way to survive.

     摘要:   阅读全文

安装和配置简述

    * 英文指南
    * 配置tomcat
          o 修改 server.xml ,在connector 加 URIEncoding="UTF-8"
          o 修改 catalina.sh ,加一行 CATALINA_OPTS="-DHUDSON_HOME=~/apprun/hudsonhome/ -Xms512m -Xmx512m"
                + 其中 HUDSON_HOME 是 hudson 的配置和运行文件所在地
          o 修改 tomcat-users.xml
                + <role rolename="admin"/>
                + <user username="hudson" password="hudson" roles="admin"/>
    * 把下载的hudson.war 放在 tomcat 的webapps 下，hudson 会自动启动起来，部署就完成了
          o 可以访问，比如 http://****:18080/hudson/
    * 安装 jdk
    * 安装 ant
    * 配置hudson
          o 配置和管理需要登陆 ，login
          o 打开管理页面，比如 http://****:18080/hudson/configure
          o 配置安全 ，Enable security ，两个选项：Delegate to servlet container --〉Legacy mode
          o 配置 jdk 路径， 比如 /home/**/tools/jdk1.6.0_13/
          o 配置 ant 路径， 比如 /home/**/apprun/ant171
          o 配置 System Admin E-mail Address ，//写一个很多项目公用的email
          o 记得 save
    * 新建一个job
          o 配置和管理需要登陆 ，login
          o new job ,选项 ：Build a free-style software project
          o 配置 ，比如 ：**:18080/hudson/job/icontent/configure
                + 填写svn 路径 ，比如 ：http://svn.****
                + Build Triggers，选Poll SCM ，schedule 符合 cron 规则
                + Build ，invoke ant ,填写 ant target
                + Post-build Actions ,选 E-mail Notification , Recipients 填写邮件地址
    * 配置linux 的环境变量
          o vi .bash_profile
          o JAVA_HOME=$HOME/tools/jdk1.6.0_13
          o PATH=$JAVA_HOME/bin:$PATH:$HOME/bin:$HOME/apprun/ant171/bin
          o LANG=zh_CN.GB2312 //encoding 与.java 源代码文件的编码一致 ，这样javadoc 不会有警告
          o LC_CTYPE=zh_CN.GB2312

easy！
great tool!

1. hibernate 变得不太重要了，jdbc 就很好
2. 数据库不够用了,bdb
3. bdb 不够用了， 自己写b+ tree
4. java 不行了，得用 c++

看来，这个转变是个革命。搞不好得丢饭碗。

从想做一个创业者，到想做一个proferssional 。

<西津渡图解软件项目管理 〉从1年半之前，每当有新的感受，就修订一些。为自己的成长作个备注吧。

code-block with mingw ,setup .
set path=c:\program file\code blocks\mingw\bin;%path%
bjam --toolset=gcc-3.4.5 --prefix=d:\boost\b137345 --build-type=complete install

很久没有来blogjava 了。
一个原因是，关注的内容与blogjava 的东西，重叠的太少了。
不过，我也纳闷，我该去哪里找自己的同好？
blogjava 在云计算，web2.0 ，这些前途领域，没有什么内容。
struts,hibernate,spring, acegi,lucene 这些都是成熟的东西了。
说一下我最近用过的东西：
hadoop,hbase,zookeeper，深入研究了java concurrent.

下一步的方向是写一个,distribute document oriented file system.

技术和互联网的发展，绝对是web2.0,云计算，两端厚的架构。blogjava 也该多这方面的内容了。

Conducting and Reviewing the Software Design Model

      The design model resides at the core of the software engineering process. It is the place where quality is built into the software (and the place where quality is assessed. For this checklist, the more questions that elicit a negative response, the higher the risk that the analysis model will adequately serve its purpose. . For this checklist, the more questions that elicit a negative response, the higher the risk that the design model will not adequately serve its purpose.

      General issues:

          o Does the overall design implement all explicit requirements? Has a traceability table been developed?

      设计对需求的匹配？



          o Does the overall design achieve all implicit requirements?

          
    
          o Is the design represented in a form that is easily understood by outsiders?

        易理解？

          o Is design notation standardized? Consistent?

        

          o Does the overall design provide sufficient information for test case design?

        可测试。

          o Is the design created using recognizable architectural and procedural patterns?

        常用的架构 和模式？
        

          o Does the design strive to incorporate reusable components?

        重用组件？

          o Is the design modular?

        模块化

          o Has the design defined both procedural and data abstractions that can be reused?
        重用的过程 / 数据 抽象？
        

          o Has the design been defined and represented in a stepwise fashion?
        逐渐细化的表述？    

          o Has the resultant software architecture been partitioned for ease of implementation? Maintenance?
        可部署性？ 可维护性？


          o Have the concepts of information hiding and functional independence been followed throughout the design?

           封装性？

          o Has a Design Specification been developed for the software?

        文档？


      For data design:

          o Have data objected defined in the analysis model been properly translated into required data structured?

        数据映射with analysis？        

          o Do the data structures contain all attributes defined in the analysis model?
        数据属性？

          o Have any new data structures and/or attributes been defined at design time?

        新的数据结构？

          o How do any new data structures and/or attributes related to the analysis model and to overall user requirements?

        用户需求与数据结构匹配吗？

          o Have the simplest data structures required to do the job been chosen?

        数据结构简单吗？

          o Can the data structures be implemented directly in the programming language of choice?

        编程语言适合数据结构？

          o How are data communicated between software components?
        软件组件之间的数据交换？

          o Do explicit data components (e.g., a database) exist? If so, what is their role?

        数据库？

      For architectural design:

          o Has a library of architectural styles been considered prior to the definition of the resultant software architecture?
        
        架构模式？

          o Has architectural tradeoff analysis been performed?
        架构分析的tradeoff？

          o Is the resultant software architecture a recognizable architectural style?

        认可的架构风格？

          o Has the architecture been exercised against existing usage scenarios?
        架构有应用示例吗？    

          o Has an appropriate mapping been used to translate the analysis model into the architectural model?
        
        分析和架构之间的mapping？

          o Can quality characteristics associated with the resultant architecture (e.g., a factored call-and-return architecture) be readily identified from information provided in the design model?
        架构的质量特点？


      For user interface design:

          o Have the results of task analysis been documented?
          o Have goals for each user task been identified?
          o Has an action sequence been defined for each user task?
          o Have various states of the interface been documented?
          o Have objects and actions that appear within the context of the interface been defined?
          o Have the three "golden rules" (SEPA, 5/e, p. 402) been maintained throughout the GUI design?
          o Has flexible interaction been defined as a design criterion throughout the interface?
          o Have expert and novice modes of interaction been defined?
          o Have technical internals been hidden from the causal user?
          o Is the on-screen metaphor (if any) consistent with the overall applications?
          o Are icons clear and understandable?
          o Is interaction intuitive?
          o Is system response time consistent across all tasks?
          o Has an integrated help facility been implemented?
          o Are all error message displayed by the interface easy to understand? Do they help the user resolve the problem quickly?
          o Is color being used effectively?
          o Has a prototype for the interface been developed?
          o Have user's impressions of the prototype been collected in an organized manner?

      For component-level design:

    * Have proof of correctness techniques (SEPA, 5/e, Chapter 26) been applied to all algorithms?

    算法正确性？

    * Has each algorithm been "desk-tested" to uncover errors? Is each algorithm correct?

    算法？

    * Is the design of the algorithm consistent with the data structured that the component manipulates?

    算法？
    * Have algorithmic design alternatives been considered? If yes, why was this design chosen?

    替代算法考虑了吗？

    * Has the complexity of each algorithm been computed?
    
    每个算法的复杂性考虑了吗？

    * Have structured programming constructs been used throughout?
    
    结构好吗？

     摘要:   阅读全文

西津渡最近在修改 99街购物搜索引擎，www.99jie.com
根据体会，修订了图解软件项目管理一文。这是今年以来的第三次较大修订。
有需要者请下载。西津渡图解软件项目管理
下边是目录。
第一章 项目管理的目标
一、    产品，周期，成本的约束。
二、    关键路径管理
三、    可行性分析很重要
四、    人际技巧
五、    谈判技巧
第二章 项目过程
一、    计划阶段
二、    架构阶段和技术攻关
三、    迭代阶段
四、    结束阶段
第三章 分析,形成specification
一、    最重要的是specification 发挥作用
二、    重要的创造性工作
三、    选择适合的表达方式
四、    数据以及数据的key 和约束
五、    测试脚本
六、    Review ,评审
第四章 设计系统UI
一、    一幅图胜过千句话
第五章 设计,code ,build ,test
第六章 部署和重构
第七章 风险
一、    分析风险
二、    技术风险
三、    所有的风险是人的风险，trust and capable
四、    记住50%以上的软件项目以失败告终
五、    所有的风险是管理的风险，遵循一套项目管理哲学
第八章 保持项目的进展
一、    对项目负责，做出决定
二、    让进展可见，持续集成
三、执行，并检查
四、    解决冲突，大家都是兄弟姐妹
五、    能担当者是项目经理
六、    关键路径的变更
第九章 总结经验
第十章 一些效率关键指标
第十一章 项目管理工具
第十二章 参考
第十三章 口诀

http://www.xker.com/edu/dev/104/0652109570034579.html

十二、不要在循环中调用synchronized(同步)方法

方法的同步需要消耗相当大的资料，在一个循环中调用它绝对不是一个好主意。

例子：
import java.util.Vector;
public class SYN {
    public synchronized void method (Object o) {
    }
    private void test () {
        for (int i = 0; i < vector.size(); i++) {
            method (vector.elementAt(i));    // violation
        }
    }
    private Vector vector = new Vector (5, 5);
}

更正：
不要在循环体中调用同步方法，如果必须同步的话，推荐以下方式：
import java.util.Vector;
public class SYN {
    public void method (Object o) {
    }
private void test () {
    synchronized{//在一个同步块中执行非同步方法
            for (int i = 0; i < vector.size(); i++) {
                method (vector.elementAt(i));   
            }
        }
    }
    private Vector vector = new Vector (5, 5);
}

十三、将try/catch块移出循环

把try/catch块放入循环体内，会极大的影响性能，如果编译JIT被关闭或者你所使用的是一个不带JIT的JVM，性能会将下降21%之多!
         
例子：         
import java.io.FileInputStream;
public class TRY {
    void method (FileInputStream fis) {
        for (int i = 0; i < size; i++) {
            try {                                      // violation
                _sum += fis.read();
            } catch (Exception e) {}
        }
    }
    private int _sum;
}
         
更正：         
将try/catch块移出循环         
    void method (FileInputStream fis) {
        try {
            for (int i = 0; i < size; i++) {
                _sum += fis.read();
            }
        } catch (Exception e) {}
    }
         
参考资料：
Peter Haggar: "Practical Java - Programming Language Guide".
Addison Wesley, 2000, pp.81 – 83

十九、不要在循环体中实例化变量

在循环体中实例化临时变量将会增加内存消耗

例子：         
import java.util.Vector;
public class LOOP {
    void method (Vector v) {
        for (int i=0;i < v.size();i++) {
            Object o = new Object();
            o = v.elementAt(i);
        }
    }
}
         
更正：         
在循环体外定义变量，并反复使用         
import java.util.Vector;
public class LOOP {
    void method (Vector v) {
        Object o;
        for (int i=0;i<v.size();i++) {
            o = v.elementAt(i);
        }
    }
}

二十一、尽可能的使用栈变量

如果一个变量需要经常访问，那么你就需要考虑这个变量的作用域了。static? local?还是实例变量？访问静态变量和实例变量将会比访问局部变量多耗费2-3个时钟周期。
         
例子：
public class USV {
    void getSum (int[] values) {
        for (int i=0; i < value.length; i++) {
            _sum += value[i];           // violation.
        }
    }
    void getSum2 (int[] values) {
        for (int i=0; i < value.length; i++) {
            _staticSum += value[i];
        }
    }
    private int _sum;
    private static int _staticSum;
}     
         
更正：         
如果可能，请使用局部变量作为你经常访问的变量。
你可以按下面的方法来修改getSum()方法：         
void getSum (int[] values) {
    int sum = _sum;  // temporary local variable.
    for (int i=0; i < value.length; i++) {
        sum += value[i];
    }
    _sum = sum;
}
         
参考资料：         
Peter Haggar: "Practical Java - Programming Language Guide".
Addison Wesley, 2000, pp.122 – 125

http://www.javafan.net/menu/jczs/200701/20070108185247.html

1). 简单的认为 .append() 效率好于 "+" 是错误的！
    2). 不要使用 new 创建 String
    3). 注意 .intern() 的使用
    4). 在编译期能够确定字符串值的情况下，使用"+"效率最高
    5). 避免使用 "+=" 来构造字符串
    6). 在声明StringBuffer对象的时候，指定合适的capacity，不要使用默认值(18)
    7). 注意以下二者的区别不一样
        - String s = "a" + "b";
        - String s = "a";
          s += "b";

关键点
1. 无论何时只要可能的话使用字符串字面量来常见字符串而不是使用new关键字来创建字符串。
2. 无论何时当你要使用new关键字来创建很多内容重复的字符串的话，请使用String.intern()方法。
3. +操作符会为字符串连接提供最佳的性能――当字符串是在编译期决定的时候。
4. 如果字符串在运行期决定，使用一个合适的初期容量值初始化的StringBuffer会为字符串连接提供最佳的性能。