最近在翻看NameNode的log時發現經常有這一段信息出現：



看來是SecondNameNode在向NameNode獲取Image時出的問題。雖然不影響hdfs使用，但是SecondName
備份功能失效，任其下去萬一NameNode掛了那可就無處申冤了。
經過Google大神幫助，得知需要在hdfs-site.xml中手動配置dfs.secondary.http.address，這個配置項的默認值如下

1、IE有全局event對象window.event，FF沒有，FF中的?event?只能在事件發生的現場使用，即必須通過事件綁定函數的參數來使用。


2、FireFox下沒有preserveWhiteSpace這個屬性，即:把空白也當作一個節點。而IE則默認為false，即把空白不看成一個節點。所以在FireFox下previousSibling可能是空白節點，除非兩個HTML標簽之間沒有任何形式的空格。

3、IE下可以用document.frames("name").document的方式取得frame中所嵌頁面的document對象，FF下卻會得到null，解決的的辦法是document.getElementById(framename).contentWindow.document，也可以使用
window.frames[frameName].document 直接獲取frame里的document對象


最后推薦一篇文章：Javascript的IE和Firefox兼容性匯編

在Hibernate中配置Proxool連接池
1：在applicationContext.xml中配置SessionFactory
<bean?id="sessionfactory"?class="org.springframework.orm.hibernate3.LocalSessionFactoryBean">
????<property?name="hibernateProperties">
????????<props>
????????????<prop?key="hibernate.dialect">org.hibernate.dialect.Oracle9Dialect</prop>
????????????<prop?key="hibernate.show_sql">true</prop>
????????????<!--指定Proxool配置文件-->
????????????<prop?key="hibernate.proxool.properties">conf/proxool.properties</prop>
????????????<!--<prop?key="hibernate.proxool.xml">conf/proxool.xml</prop>-->
????????????<!--指定Proxool的alias，必須與Proxool的配置文件中的alias一致-->
????????????<prop?key="hibernate.proxool.pool_alias">hibernate-oracle</prop>
????????</props>
????</property>
</bean>
2：配置Proxool(conf/proxool.properties)
#jdbc-0.proxool.alias=mysql
#jdbc-0.proxool.driver-class=org.gjt.mm.mysql.Driver
#jdbc-0.proxool.driver-url=jdbc:mysql://localhost:3306/contestdb?user=root&password=1234&useUnicode=true&characterEncoding=utf8
#jdbc-0.user=root
#jdbc-0.password=1234

jdbc-0.proxool.alias=hibernatea-oracle
jdbc-0.proxool.driver-class=oracle.jdbc.driver.OracleDriver
jdbc-0.proxool.driver-url=jdbc:oracle:thin:@172.16.2.6:1521:dbname
jdbc-0.user=username
jdbc-0.password=username
jdbc-0.proxool.maximum-connection-count=20
jdbc-0.proxool.house-keeping-test-sql=SELECT?SYSDATE?FROM?DUAL;
#DEBUG,?INFO,?WARN,?ERROR,?FATAL.
jdbc-0.proxool.statistics-log-level=ERROR

???????? The?URL?extension?to?use?to?determine?if?the?request?is?meant?for?a?Struts?action?
???????????用URL擴展名來確定是否這個請求是被用作Struts?action，其實也就是設置?action的后綴，例如login.do的'do'字。

struts.configuration
??????????The?org.apache.struts2.config.Configuration?implementation?class
????????????org.apache.struts2.config.Configuration接口名

struts.configuration.files
??????????A?list?of?configuration?files?automatically?loaded?by?Struts?
???????????struts自動加載的一個配置文件列表

struts.configuration.xml.reload
??????????Whether?to?reload?the?XML?configuration?or?not
???????????是否加載xml配置(true,false)

struts.continuations.package
???????????The?package?containing?actions?that?use?Rife?continuations
???????????含有actions的完整連續的package名稱

struts.custom.i18n.resources
??????????Location?of?additional?localization?properties?files?to?load?
???????????加載附加的國際化屬性文件（不包含.properties后綴）

struts.custom.properties
??????????Location?of?additional?configuration?properties?files?to?load
???????????加載附加的配置文件的位置


struts.devMode
??????????Whether?Struts?is?in?development?mode?or?not
???????????是否為struts開發模式

struts.dispatcher.parametersWorkaround
??????????Whether?to?use?a?Servlet?request?parameter?workaround?necessary?for?some?versions?of?WebLogic
????????????（某些版本的weblogic專用）是否使用一個servlet請求參數工作區（PARAMETERSWORKAROUND）

struts.enable.DynamicMethodInvocation
??????????Allows?one?to?disable?dynamic?method?invocation?from?the?URL
????????????允許動態方法調用

struts.freemarker.manager.classname
??????????The?org.apache.struts2.views.freemarker.FreemarkerManager?implementation?class?
???????????org.apache.struts2.views.freemarker.FreemarkerManager接口名

struts.i18n.encoding
??????????The?encoding?to?use?for?localization?messages
???????????國際化信息內碼

struts.i18n.reload
??????????Whether?the?localization?messages?should?automatically?be?reloaded
???????????是否國際化信息自動加載?

struts.locale
??????????The?default?locale?for?the?Struts?application
???????????默認的國際化地區信息

struts.mapper.class
??????????The?org.apache.struts2.dispatcher.mapper.ActionMapper?implementation?class
????????????org.apache.struts2.dispatcher.mapper.ActionMapper接口

struts.multipart.maxSize
??????????The?maximize?size?of?a?multipart?request?(file?upload)
???????????multipart請求信息的最大尺寸（文件上傳用）?

struts.multipart.parser
??????????The?org.apache.struts2.dispatcher.multipart.
??????????MultiPartRequest?parser?implementation?for?a?multipart?request?(file?upload)?
??????????專為multipart請求信息使用的org.apache.struts2.dispatcher.multipart.MultiPartRequest解析器接口（文件上傳用）


struts.multipart.saveDir
??????????The?directory?to?use?for?storing?uploaded?files?
???????????設置存儲上傳文件的目錄夾

struts.objectFactory
??????????The?com.opensymphony.xwork2.ObjectFactory?implementation?class
???????????com.opensymphony.xwork2.ObjectFactory接口（spring）

struts.objectFactory.spring.autoWire
??????????Whether?Spring?should?autoWire?or?not
???????????是否自動綁定Spring

struts.objectFactory.spring.useClassCache
??????????Whether?Spring?should?use?its?class?cache?or?not
???????????是否spring應該使用自身的cache?

struts.objectTypeDeterminer
??????????The?com.opensymphony.xwork2.util.ObjectTypeDeterminer?implementation?class
????????????com.opensymphony.xwork2.util.ObjectTypeDeterminer接口

struts.serve.static.browserCache
??If?static?content?served?by?the?Struts?filter?should?set?browser?caching?header?properties?or?not?
???????????是否struts過濾器中提供的靜態內容應該被瀏覽器緩存在頭部屬性中

struts.serve.static
??????????Whether?the?Struts?filter?should?serve?static?content?or?not?
???????????是否struts過濾器應該提供靜態內容

struts.tag.altSyntax
??????????Whether?to?use?the?alterative?syntax?for?the?tags?or?not?
???????????是否可以用替代的語法替代tags

struts.ui.templateDir
??????????The?directory?containing?UI?templates
???????????UI?templates的目錄夾?

struts.ui.theme
??????????The?default?UI?template?theme
???????????默認的UI?template主題

struts.url.http.port
??????????The?HTTP?port?used?by?Struts?URLs
???????????設置http端口

struts.url.https.port
??????????The?HTTPS?port?used?by?Struts?URLs?
???????????設置https端口

struts.url.includeParams
??????????The?default?includeParams?method?to?generate?Struts?URLs?
??????????在url中產生?默認的includeParams


struts.velocity.configfile
??????????The?Velocity?configuration?file?path
???????????velocity配置文件路徑

struts.velocity.contexts
??????????List?of?Velocity?context?names
???????????velocity的context列表


struts.velocity.manager.classname
??????????org.apache.struts2.views.velocity.VelocityManager?implementation?class
???????????org.apache.struts2.views.velocity.VelocityManager接口名

struts.velocity.toolboxlocation
??????????The?location?of?the?Velocity?toolbox
???????????velocity工具盒的位置?
struts.xslt.nocache
??????????Whether?or?not?XSLT?templates?should?not?be?cached
???????????是否XSLT模版應該被緩存