Solr 5.5.0 + tomcat 7.0.69 + zookeeper-3.4.6 Cloud部署
Solr介绍:
Solr是一个独立的企业级搜索应用服务器,Solr基于Lucene的全文搜索服务器,同时对其进行了扩展,提供了比Lucene更为丰富的查询语言,同时实现了可配置、可扩展并对查询性能进行了优化,并且提供了一个完善的功能管理界面,是一款非常优秀的全文搜索引擎。Solr对外提供类似于Web-service的API接口。用户可以通过http请求,向搜索引擎服务器提交一定格式的XML文件/Json/文本等,生成索引;也可以通过Http Get操作提出查找请求,并得到Json格式的返回结果。
项目引入Solr时应该考虑的一些问题:
1、数据更新频率:每天数据增量有多大,随时更新还是定时更新
2、数据总量:数据要保存多长时间
3、一致性要求:期望多长时间内看到更新的数据,最长允许多长时间延迟
4、数据特点:数据源包括哪些,平均单条记录大小
5、业务特点:有哪些排序要求,检索条件
6、资源复用:已有的硬件配置是怎样的,是否有升级计划
SolrCloud:Solr分布式扩展方案
SolrCloud是基于ZooKeeper和Solr的分布式解决方案,为Solr添加分布式功能,用于建立高可用,高伸缩,自动容错,分布式索引,分布式查询的Solr服务器集群
它有几个特色功能:
1)集中式的配置信息
2)自动容错
3)近实时搜索
4)查询时自动负载均衡
Solr 5.5.0 + tomcat 7.0.69 + zookeeper-3.4.6 Cloud部署
(本文因为机器不够,只能在单机环境伪分布式部署,模拟4台真实机器,真实部署可将tomcat/zookeeper的端口不做调整即可)
4台tomcat组成下述部署方案:Collection分成两个Shard分别存储索引信息,每个Shard又分成两个core_node(一主一备)来调配索引最终配置完成结果如下:
(1)
apache-tomcat-7.0.69集群配置:
版本:apache-tomcat-7.0.69
下载:http://tomcat.apache.org/download-70.cgi
位置:/var/local/
数量:4台:/var/local/apache-tomcat-7.0.69-1,/var/local/apache-tomcat-7.0.69-2,/var/local/apache-tomcat-7.0.69-3,/var/local/apache-tomcat-7.0.69-4
说明:主要调整单机环境下tomcat的端口冲突
apache-tomcat-7.0.69-1
sudo vi /var/local/apache-tomcat-7.0.69-1/conf/server.xml
{
<Server port="18005" shutdown="SHUTDOWN">
<Connector port="18080" protocol="HTTP/1.1" connectionTimeout="20000" redirectPort="8443" />
<Connector port="18009" protocol="AJP/1.3" redirectPort="8443" />
}
apache-tomcat-7.0.69-2
{
sudo vi /var/local/apache-tomcat-7.0.69-2/conf/server.xml
<Server port="28005" shutdown="SHUTDOWN">
<Connector port="28080" protocol="HTTP/1.1" connectionTimeout="20000" redirectPort="8443" />
<Connector port="28009" protocol="AJP/1.3" redirectPort="8443" />
}
apache-tomcat-7.0.69-3
sudo vi /var/local/apache-tomcat-7.0.69-3/conf/server.xml
{
<Server port="38005" shutdown="SHUTDOWN">
<Connector port="38080" protocol="HTTP/1.1" connectionTimeout="20000" redirectPort="8443" />
<Connector port="38009" protocol="AJP/1.3" redirectPort="8443" />
}
apache-tomcat-7.0.69-4
sudo vi /var/local/apache-tomcat-7.0.69-4/conf/server.xml
{
<Server port="48005" shutdown="SHUTDOWN">
<Connector port="48080" protocol="HTTP/1.1" connectionTimeout="20000" redirectPort="8443" />
<Connector port="48009" protocol="AJP/1.3" redirectPort="8443" />
}
(2)
zookeeper-3.4.6集群配置:
版本:zookeeper-3.4.6
下载:https://zookeeper.apache.org/releases.html#download
位置:/var/local/
数量:4台:/var/local/zookeeper-3.4.6-1,/var/local/zookeeper-3.4.6-2,/var/local/zookeeper-3.4.6-3,/var/local/zookeeper-3.4.6-4
说明:主要调整单机环境下zookeeper的端口及目录冲突
zookeeper-3.4.6-1
sudo mkdir -p /var/local/zookeeper-3.4.6-1/data
sudo mkdir -p /var/local/zookeeper-3.4.6-1/data/log
echo 1 > /var/local/zookeeper-3.4.6-1/data/myid (sudo vi /var/local/zookeeper-3.4.6-1/data/myid {1})
cd /var/local/zookeeper-3.4.6-1/conf/ &&sudo mv zoo_sample.cfg zoo.cfg &&sudo vi zoo.cfg
{
clientPort=2181
dataDir=/var/local/zookeeper-3.4.6-1/data
dataLogDir=/var/local/zookeeper-3.4.6-1/data/log
autopurge.snapRetainCount=3
autopurge.purgeInterval=1
server.1=127.0.0.1:2888:3888
server.2=127.0.0.1:2889:3889
server.3=127.0.0.1:2890:3890
server.4=127.0.0.1:2891:3891
}
zookeeper-3.4.6-2
sudo cp -r /var/local/zookeeper-3.4.6-1 /var/local/zookeeper-3.4.6-2
sudo vi /var/local/zookeeper-3.4.6-2/data/myid {2}
sudo vi /var/local/zookeeper-3.4.6-2/conf/zoo.cfg
{
clientPort=2182
dataDir=/var/local/zookeeper-3.4.6-2/data
dataLogDir=/var/local/zookeeper-3.4.6-2/data/log
autopurge.snapRetainCount=3
autopurge.purgeInterval=1
server.1=127.0.0.1:2888:3888
server.2=127.0.0.1:2889:3889
server.3=127.0.0.1:2890:3890
server.4=127.0.0.1:2891:3891
}
zookeeper-3.4.6-3
sudo cp -r /var/local/zookeeper-3.4.6-1 /var/local/zookeeper-3.4.6-3
sudo vi /var/local/zookeeper-3.4.6-3/data/myid {3}
sudo vi /var/local/zookeeper-3.4.6-3/conf/zoo.cfg
{
clientPort=2183
dataDir=/var/local/zookeeper-3.4.6-3/data
dataLogDir=/var/local/zookeeper-3.4.6-3/data/log
autopurge.snapRetainCount=3
autopurge.purgeInterval=1
server.1=127.0.0.1:2888:3888
server.2=127.0.0.1:2889:3889
server.3=127.0.0.1:2890:3890
server.4=127.0.0.1:2891:3891
}
zookeeper-3.4.6-4
sudo cp -r /var/local/zookeeper-3.4.6-1 /var/local/zookeeper-3.4.6-4
sudo vi /var/local/zookeeper-3.4.6-4/data/myid {4}
sudo vi /var/local/zookeeper-3.4.6-4/conf/zoo.cfg
{
clientPort=2184
dataDir=/var/local/zookeeper-3.4.6-4/data
dataLogDir=/var/local/zookeeper-3.4.6-4/data/log
autopurge.snapRetainCount=3
autopurge.purgeInterval=1
server.1=127.0.0.1:2888:3888
server.2=127.0.0.1:2889:3889
server.3=127.0.0.1:2890:3890
server.4=127.0.0.1:2891:3891
}
(3)
solr-5.5.0集群配置:
版本:solr-5.5.0
下载:https://mirrors.tuna.tsinghua.edu.cn/apache/lucene/solr/5.5.0/
位置:/var/local/apache-tomcat-7.0.69-1~4
公有配置文件:/var/local/cloud_conf
数量:4台:/var/local/apache-tomcat-7.0.69-1,/var/local/apache-tomcat-7.0.69-2,/var/local/apache-tomcat-7.0.69-3,/var/local/apache-tomcat-7.0.69-4
Solr WEB系统部署:
sudo cp -r ~/solr_cloud/solr-5.5.0/server/solr-webapp/webapp /var/local/apache-tomcat-7.0.69-1/webapps/solr
sudo cp -r ~/solr_cloud/solr-5.5.0/server/lib/ext/* /var/local/apache-tomcat-7.0.69-1/webapps/solr/WEB-INF/lib (其他需要用的jar包自行复制即可:~/solr_cloud/solr-5.5.0/dist/)
sudo cp -r ~/solr_cloud/solr-5.5.0/server/resources/log4j.properties /var/local/apache-tomcat-7.0.69-1/webapps/solr/WEB-INF/classes (classes若不存在则手动建立)
solr-5.5.0-1
sudo mkdir -p /var/local/apache-tomcat-7.0.69-1/solr_home/
sudo cp ~/solr_cloud/solr-5.5.0/example/example-DIH/solr/solr.xml /var/local/apache-tomcat-7.0.69-1/solr_home/
sudo vi /var/local/apache-tomcat-7.0.69-1/webapps/solr/WEB-INF/web.xml
{
<env-entry>
<env-entry-name>solr/home</env-entry-name>
<env-entry-value>/var/local/apache-tomcat-7.0.69-1/solr_home</env-entry-value>
<env-entry-type>java.lang.String</env-entry-type>
</env-entry>
}
sudo vi /var/local/apache-tomcat-7.0.69-1/bin/catalina.sh
{
JAVA_OPTS="$JAVA_OPTS -Dbootstrap_confdir=/var/local/cloud_conf -Dcollection.configName=myconf -DzkHost=127.0.0.1:2181,127.0.0.1:2182,127.0.0.1:2183,127.0.0.1:2184 -DnumShards=4"
}
sudo vi /var/local/apache-tomcat-7.0.69-1/solr_home/solr.xml
{
<solrcloud>
<str name="host">${host:}</str>
<int name="hostPort">18080</int>
<str name="hostContext">${hostContext:solr}</str>
<int name="zkClientTimeout">${zkClientTimeout:15000}</int>
<bool name="genericCoreNodeNames">${genericCoreNodeNames:true}</bool>
<str name="zkHost">127.0.0.1:2181,127.0.0.1:2182,127.0.0.1:2183,127.0.0.1:2184</str>
</solrcloud>
<shardHandlerFactory name="shardHandlerFactory"
class="HttpShardHandlerFactory">
<int name="socketTimeout">${socketTimeout:0}</int>
<int name="connTimeout">${connTimeout:0}</int>
</shardHandlerFactory>
}
solr-5.5.0-2
sudo mkdir -p /var/local/apache-tomcat-7.0.69-2/solr_home/
sudo cp -r /var/local/apache-tomcat-7.0.69-1/solr_home/* /var/local/apache-tomcat-7.0.69-2/solr_home/
sudo cp -r /var/local/apache-tomcat-7.0.69-1/webapps/solr /var/local/apache-tomcat-7.0.69-2/webapps/
sudo vi /var/local/apache-tomcat-7.0.69-2/webapps/solr/WEB-INF/web.xml
{
<env-entry>
<env-entry-name>solr/home</env-entry-name>
<env-entry-value>/var/local/apache-tomcat-7.0.69-2/solr_home</env-entry-value>
<env-entry-type>java.lang.String</env-entry-type>
</env-entry>
}
sudo vi /var/local/apache-tomcat-7.0.69-2/bin/catalina.sh
{
JAVA_OPTS="$JAVA_OPTS -DzkHost=127.0.0.1:2181,127.0.0.1:2182,127.0.0.1:2183,127.0.0.1:2184"
}
sudo vi /var/local/apache-tomcat-7.0.69-2/solr_home/solr.xml
{
<solrcloud>
<str name="host">${host:}</str>
<int name="hostPort">28080</int>
<str name="hostContext">${hostContext:solr}</str>
<int name="zkClientTimeout">${zkClientTimeout:15000}</int>
<bool name="genericCoreNodeNames">${genericCoreNodeNames:true}</bool>
<str name="zkHost">127.0.0.1:2181,127.0.0.1:2182,127.0.0.1:2183,127.0.0.1:2184</str>
</solrcloud>
<shardHandlerFactory name="shardHandlerFactory"
class="HttpShardHandlerFactory">
<int name="socketTimeout">${socketTimeout:0}</int>
<int name="connTimeout">${connTimeout:0}</int>
</shardHandlerFactory>
}
solr-5.5.0-3
sudo mkdir -p /var/local/apache-tomcat-7.0.69-3/solr_home/
sudo cp -r /var/local/apache-tomcat-7.0.69-1/solr_home/* /var/local/apache-tomcat-7.0.69-3/solr_home/
sudo cp -r /var/local/apache-tomcat-7.0.69-1/webapps/solr /var/local/apache-tomcat-7.0.69-3/webapps/
sudo vi /var/local/apache-tomcat-7.0.69-3/webapps/solr/WEB-INF/web.xml
{
<env-entry>
<env-entry-name>solr/home</env-entry-name>
<env-entry-value>/var/local/apache-tomcat-7.0.69-3/solr_home</env-entry-value>
<env-entry-type>java.lang.String</env-entry-type>
</env-entry>
}
sudo vi /var/local/apache-tomcat-7.0.69-3/bin/catalina.sh
{
JAVA_OPTS="$JAVA_OPTS -DzkHost=127.0.0.1:2181,127.0.0.1:2182,127.0.0.1:2183,127.0.0.1:2184"
}
sudo vi /var/local/apache-tomcat-7.0.69-3/solr_home/solr.xml
{
<solrcloud>
<str name="host">${host:}</str>
<int name="hostPort">38080</int>
<str name="hostContext">${hostContext:solr}</str>
<int name="zkClientTimeout">${zkClientTimeout:15000}</int>
<bool name="genericCoreNodeNames">${genericCoreNodeNames:true}</bool>
<str name="zkHost">127.0.0.1:2181,127.0.0.1:2182,127.0.0.1:2183,127.0.0.1:2184</str>
</solrcloud>
<shardHandlerFactory name="shardHandlerFactory"
class="HttpShardHandlerFactory">
<int name="socketTimeout">${socketTimeout:0}</int>
<int name="connTimeout">${connTimeout:0}</int>
</shardHandlerFactory>
}
solr-5.5.0-4
sudo mkdir -p /var/local/apache-tomcat-7.0.69-4/solr_home/
sudo cp -r /var/local/apache-tomcat-7.0.69-1/solr_home/* /var/local/apache-tomcat-7.0.69-4/solr_home/
sudo cp -r /var/local/apache-tomcat-7.0.69-1/webapps/solr /var/local/apache-tomcat-7.0.69-4/webapps/
sudo vi /var/local/apache-tomcat-7.0.69-4/webapps/solr/WEB-INF/web.xml
{
<env-entry>
<env-entry-name>solr/home</env-entry-name>
<env-entry-value>/var/local/apache-tomcat-7.0.69-4/solr_home</env-entry-value>
<env-entry-type>java.lang.String</env-entry-type>
</env-entry>
}
sudo vi /var/local/apache-tomcat-7.0.69-4/bin/catalina.sh
{
JAVA_OPTS="$JAVA_OPTS -DzkHost=127.0.0.1:2181,127.0.0.1:2182,127.0.0.1:2183,127.0.0.1:2184"
}
sudo vi /var/local/apache-tomcat-7.0.69-4/solr_home/solr.xml
{
<solrcloud>
<str name="host">${host:}</str>
<int name="hostPort">48080</int>
<str name="hostContext">${hostContext:solr}</str>
<int name="zkClientTimeout">${zkClientTimeout:15000}</int>
<bool name="genericCoreNodeNames">${genericCoreNodeNames:true}</bool>
<str name="zkHost">127.0.0.1:2181,127.0.0.1:2182,127.0.0.1:2183,127.0.0.1:2184</str>
</solrcloud>
<shardHandlerFactory name="shardHandlerFactory"
class="HttpShardHandlerFactory">
<int name="socketTimeout">${socketTimeout:0}</int>
<int name="connTimeout">${connTimeout:0}</int>
</shardHandlerFactory>
}
(5)
启动及说明:
启动tomcat集群
sudo /var/local/apache-tomcat-7.0.69-1/bin/startup.sh &&sudo /var/local/apache-tomcat-7.0.69-2/bin/startup.sh &&sudo /var/local/apache-tomcat-7.0.69-3/bin/startup.sh &&sudo /var/local/apache-tomcat-7.0.69-4/bin/startup.sh
关闭tomcat集群
sudo /var/local/apache-tomcat-7.0.69-1/bin/shutdown.sh &&sudo /var/local/apache-tomcat-7.0.69-2/bin/shutdown.sh &&sudo /var/local/apache-tomcat-7.0.69-3/bin/shutdown.sh &&sudo /var/local/apache-tomcat-7.0.69-4/bin/shutdown.sh
启动zookeeper集群
sudo /var/local/zookeeper-3.4.6-1/bin/zkServer.sh restart && sudo /var/local/zookeeper-3.4.6-2/bin/zkServer.sh restart &&sudo /var/local/zookeeper-3.4.6-3/bin/zkServer.sh restart &&sudo /var/local/zookeeper-3.4.6-4/bin/zkServer.sh restart
sudo /var/local/zookeeper-3.4.6-1/bin/zkServer.sh stop && sudo /var/local/zookeeper-3.4.6-2/bin/zkServer.sh stop &&sudo /var/local/zookeeper-3.4.6-3/bin/zkServer.sh stop
查看zookeeper集群状态
sudo /var/local/zookeeper-3.4.6-1/bin/zkServer.sh status &&sudo /var/local/zookeeper-3.4.6-2/bin/zkServer.sh status &&sudo /var/local/zookeeper-3.4.6-3/bin/zkServer.sh status &&sudo /var/local/zookeeper-3.4.6-4/bin/zkServer.sh status
访问Solr Web系统:(192.168.5.48即本机IP)
http://192.168.5.48:18080/solr/index.html
http://192.168.5.48:28080/solr/index.html
http://192.168.5.48:38080/solr/index.html
http://192.168.5.48:48080/solr/index.html
上述地址均可访问及管理Solr Web系统
说明:
1)solr-5.5.0中会出现在Collection中点击query命令时,误将地址栏 / 转义为 %2F 的bug,如下:
http://192.168.5.48:18080/solr/test1%2Fselect?indent=on&q=*:*&wt=json
2)solr-5.5.0中自带的zookeeper-3.4.6.jar,因此建议zookeeper选用-3.4.6版本的
3)solr-5以上的schema由managed-schema通过API管理,在solrconfig.xml中可以查看到:
<!-- To disable dynamic schema REST APIs, use the following for <schemaFactory>:
<schemaFactory class="ClassicIndexSchemaFactory"/>
When ManagedIndexSchemaFactory is specified instead, Solr will load the schema from
the resource named in 'managedSchemaResourceName', rather than from schema.xml.
Note that the managed schema resource CANNOT be named schema.xml. If the managed
schema does not exist, Solr will create it after reading schema.xml, then rename
'schema.xml' to 'schema.xml.bak'.
Do NOT hand edit the managed schema - external modifications will be ignored and
overwritten as a result of schema modification REST API calls.
When ManagedIndexSchemaFactory is specified with mutable = true, schema
modification REST API calls will be allowed; otherwise, error responses will be
sent back for these requests.
-->
<schemaFactory class="ManagedIndexSchemaFactory">
<bool name="mutable">true</bool>
<str name="managedSchemaResourceName">managed-schema</str>
</schemaFactory>
4)schema部分说明:
Stored:字段值会以保存一份原始内容在在索引中,可以被搜索组件组件返回,考虑到性能问题,对于长文本就不适合存储在索引中。
Indexed:表示字段会加被Sorl处理加入到索引中,只有被索引的字段才能被搜索到。
docValues: 表示此域是否需要添加一个docValues域,这对facet查询,group分组,排序,function查询有好处,能加快索引数据加载,对NRT近实时搜索比较友好,且更节省内存,但它也有一些限制,比如当前docValues域只支持strField,UUIDField,Trie*Field等域,且要求域的域值是单值不能是多值域
multiValued: 表示这个域是否可以存储多个值
omitNorms: 此属性若设置为true,即表示将忽略域值的长度标准化,忽略在索引过程中对当前域的权重设置,且会节省内存。
只有全文本域或者你需要在索引创建过程中设置域的权重时才需要把这个值设为false,对于基本数据类型且不分词的域如intFeild,longField,StrField等默认此属性值就是true,否则默认就是false.
omitPositions=true|false如果设置,省略掉term vector中的地址信息
omitTermFreqAndPositions=true|false 如果设置,省略掉freq和term vector中的地址信息
termVectors: 设置为true即表示需要为该field存储项向量信息,当你需要MoreLikeThis功能时,则需要将此属性值设为true,这样会带来一些性能提升。
termPositions: 是否存储Term的起始位置信息,这会增大索引的体积,但高亮功能需要依赖此项设置,否则无法高亮
termOffsets: 表示是否存储索引的位置偏移量,高亮功能需要此项配置,当你使用SpanQuery时,此项配置会影响匹配的结果集
sortMissingLast表示如果域值为null,在根据当前域进行排序时,把包含null值的document排在最后一位
sortMissingFirst:表示如果域值为null,在根据当前域进行排序时,把包含null值的document排在前面一位
Solr 5.5.0 + tomcat 7.0.69 + zookeeper-3.4.6 Cloud部署的更多相关文章
- 基于MyEclipse+9.0+++Tomcat+7.0的SSH+平台搭建
基于MyEclipse+9.0+++Tomcat+7.0的SSH+平台搭建 http://wenku.baidu.com/view/96fbfe0f581b6bd97f19ea1d.html 用MyE ...
- solr 3.5.0 与 tomcat 7.0.5 整合配置
1.将D:\software\lucene-3.6.0\apache-solr-3.5.0\example\solr下的文件拷贝到要作为服务器的位置(如:D:\lucene\solr\home),可以 ...
- Solr(5.1.0) 与Tomcat 从0开始安装与配置
1.什么是Solr? Solr是一个基于Lucene的Java搜索引擎服务器.Solr 提供了层面搜索.命中醒目显示并且支持多种输出格式(包括 XML/XSLT 和 JSON 格式).它易于安装和配置 ...
- Tomcat、TongWeb5.0、TongWeb6.0部署solr
将solr,solr-4.7.2复制到某一路径下,比如F盘根目录. 1.tomcat中进行配置,配置如下: <Context docBase="F:/solr" reload ...
- Linux Tomcat 6.0安装配置实践总结
系统环境: Red Hat Enterprise Linux Server release 5.7 (Tikanga) 64位 Tomcat下载 从官方网站 http://tomcat.apache ...
- Unable to load configuration. - action - file:/C:/Program%20Files/Apache%20Software%20Foundation/Tomcat%209.0/webapps/Teacher04/WEB-INF/classes/struts.xml:9:54
发布一个struts2项目的时候tomcat显示下面这个错误,我的本能感觉就是我的struts.xml或者web.xml写错了,可是我字母找都没发现,于是百度一番,可是我对那些人的回答表示怀疑,感觉应 ...
- Server Tomcat v7.0 Server at localhost was unable to start within 45 seconds
错误:Server Tomcat v7.0 Server at localhost was unable to start within 45 seconds 错误提示就是我们限定了部署的时间导致的错 ...
- Could not publish server configuration for Tomcat v6.0 Server at localhost.
经常在使用tomcat服务器的时候 总会发生一些莫名其妙的错误. 就像下面这个错误: 在配置文件中存在多个/MyWeb的配置,导致不能发布服务. 错误信息: Could not publish ser ...
- Server Tomcat v7.0 Server at localhost was unable to&nbs 报错问题解决
在eclipse启动tomcat时遇到超时45秒的问题: Server Tomcat v7.0 Server at localhost was unable to start within 45 se ...
随机推荐
- [HNOI 2018]游戏
Description 题库链接 有 \(n\) 个房间排成一列,编号为 \(1,2,...,n\) ,相邻的房间之间都有一道门.其中 \(m\) 个门上锁,其余的门都能直接打开.现在已知每把锁的钥匙 ...
- [BZOJ 3456]城市规划
Description 题库链接( bzoj 权限题,可以去 cogs 交♂ 题库链接2 求含有 \(n\) 个点有标号的简单无向联通图的个数.方案数对 \(1004535809(479\times ...
- codeforces 523D tatistics of Recompressing Videos
一个称为DH(DogHouse)的狗的社交网络有k台专用服务器来重新上传可爱的猫的上传视频.每个视频上传后,应该在一个(任何)服务器上重新压缩,之后才可以保存在社交网络中. 我们知道每个服务器需要一秒 ...
- poj 2528 (线段树+离散化)
poj 2528 For each input data set print the number of visible posters after all the posters are place ...
- [BZOJ]1071 组队(SCOI2007)
一道比较NB的套路题. Description NBA每年都有球员选秀环节.通常用速度和身高两项数据来衡量一个篮球运动员的基本素质.假如一支球队里速度最慢的球员速度为minV,身高最矮的球员高度为mi ...
- [bzoj4868][Shoi2017]期末考试
来自FallDream 的博客,未经允许,请勿转载,谢谢. 有n位同学,每位同学都参加了全部的m门课程的期末考试,都在焦急的等待成绩的公布.第i位同学希望在第ti天或之前得知所.有.课程的成绩.如果在 ...
- Linux学习之CentOS(六)---mount挂载设备(u盘,光盘,iso等 )
对于新手学习,mount 命令,一定会有很多疑问.其实我想疑问来源更多的是对linux系统本身特殊性了解问题. linux是基于文件系统,所有的设备都会对应于:/dev/下面的设备.如: [cheng ...
- Cisco 关闭命令同步提示信息
Router(config)#no logging console 如果你通过console连接,使用第一条Router(config)#no logging monitor 如果通过telnet,s ...
- 利用Runtime实现简单的字典转模型
前言 我们都知道,开发中会有这么一个过程,就是将服务器返回的数据转换成我们自己定义的模型对象.当然服务器返回的数据结构有xml类型的,也有json类型的.本文只讨论json格式的. 大家在项目中一般是 ...
- jquery datagrid添加冻结列等
frozenColumns:[[ { field: 'xh', checkbox: true }, { field: "CZ", title: "操作", wi ...