有时要为每一篇文章统计其点击次数,如果每一次浏览都要更新一次库的话,那性能在访问量很大的情况下,服务器的压力就会很大了,比较好一点的方法就是先将要更新的数据缓存起来,然后每隔一段时间再利用数据库的批量处理,批量更新库。源码如下: 1oC/W?l^
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CountBean.java s;A]GJ
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/* \]^|IViIQ
* CountData.java ,y^By_1wS
* ,5q^/h
* Created on 2007年1月1日, 下午4:44 t
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* t.m
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* To change this template, choose Tools | Options and locate the template under ivt\|
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* the Source Creation and Management node. Right-click the template and choose !-: a`Vs+
* Open. You can then make changes to the template in the Source Editor. *H;&hq
*/ 8s|r'
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package com.tot.count; WvR}c
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/** j,Mp["X&
* 4}gwMjU-B
* @author W2REwUps
*/ 4*'NpqC(_
public class CountBean { 4((Z8@iX/
private String countType; }(gXlF
int countId; ImgKqp0Z
/** Creates a new instance of CountData */ F
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public CountBean() {} DRw%~
public void setCountType(String countTypes){ |>VHV} 4)<
this.countType=countTypes; /+'@}u
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} E#T'=f[r~
public void setCountId(int countIds){ MEg|AhP
this.countId=countIds; E]Kd`&^}
} 7/Ew(X8Fs
public String getCountType(){ X~lOFH;}q
return countType; K":-zS
} 7 0KZXgBy_
public int getCountId(){ m"u 9AOH k
return countId; N#|c2n+
} #LF_*a0v
} N:=D@x~]
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CountCache.java Rb#?c+&#
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/* m`n51i{U
* CountCache.java 5C/u`{4]Hg
* F*}b),
* Created on 2007年1月1日, 下午5:01 3<B{-z
* <;M 6s~
* To change this template, choose Tools | Options and locate the template under &u$l2hSS
* the Source Creation and Management node. Right-click the template and choose |IZG`3
* Open. You can then make changes to the template in the Source Editor.
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*/ ;u, 5
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package com.tot.count; tw^V?4[Miu
import java.util.*; 5JQq?e)n
/** cpf8f i
* ~ 5`Ngpp
* @author 3"%:S_[
*/ 60-LpGhvy
public class CountCache {
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public static LinkedList list=new LinkedList(); _)lK.5
/** Creates a new instance of CountCache */ DAJh9I
public CountCache() {} 'M YqCfIK
public static void add(CountBean cb){ _Tev503
if(cb!=null){ }K0.*+M
list.add(cb); "x&H*"
} M=@U]1n*c
} MwXgaSV
} yv,9 0+k
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CountControl.java v^JyVf>
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/* yU&A[DZQ
* CountThread.java UI |D?z<
* 2qw~hWX
* Created on 2007年1月1日, 下午4:57 ;v#~o*
* h(jg7R
* To change this template, choose Tools | Options and locate the template under to+jQ9q8
* the Source Creation and Management node. Right-click the template and choose vBq2JJAl
* Open. You can then make changes to the template in the Source Editor. $O7>E!uVD
*/ v||8Q\d
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package com.tot.count; [JsQ/|=z
import tot.db.DBUtils; si0jXue~j\
import java.sql.*; u]CW5snz
/** v-4eN1OS
* H#G'q_uHH
* @author O3B\K <l
*/ r's4-\
public class CountControl{ 5zfPh`U>1
private static long lastExecuteTime=0;//上次更新时间 k2p{<SO;
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 q48V|6X'q
/** Creates a new instance of CountThread */ 7teg*M{
public CountControl() {} &&TQ0w&T
public synchronized void executeUpdate(){ yAXw?z!`O
Connection conn=null; WRL &tz
PreparedStatement ps=null; DYbkw4Z,
try{ ,]1K^UeZ
conn = DBUtils.getConnection(); $UgM7V$
conn.setAutoCommit(false); \*1pFX#
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); E.4`aJ@>d
for(int i=0;i<CountCache.list.size();i++){ =)(sN"%
CountBean cb=(CountBean)CountCache.list.getFirst(); !SKEL6~7
CountCache.list.removeFirst(); !2$O^
}6"
ps.setInt(1, cb.getCountId()); a*KB'u6&
ps.executeUpdate();⑴ =AGsW
//ps.addBatch();⑵ Z_cTuu0'
} }=az6cLE2
//int [] counts = ps.executeBatch();⑶ :1s6h%evrT
conn.commit(); teQ%t~PJ-&
}catch(Exception e){ , z<\ Z!+=
e.printStackTrace(); ,d@.@a]
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} finally{ x^;nQas;
try{ n<y!@p^X
if(ps!=null) { }"2
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ps.clearParameters(); bxK1v7
ps.close(); LH3PgGi,
ps=null; gNo.&G [
} (]0ZxWF
}catch(SQLException e){} ^t?P32GJ
DBUtils.closeConnection(conn); iw12x:
} >jq~5HN
} .COY%fz
public long getLast(){ hd8:| _
return lastExecuteTime; ccZ A
} yv[s)c}
public void run(){ / F5g@ X&
long now = System.currentTimeMillis(); $
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if ((now - lastExecuteTime) > executeSep) { :(!il?
//System.out.print("lastExecuteTime:"+lastExecuteTime); /t01z~_
//System.out.print(" now:"+now+"\n"); =k2In_
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); v;80RjPy>
lastExecuteTime=now; AN\:
executeUpdate(); BI3Q~ADV
} ix=HLF-0zC
else{ rH8w||S2U
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); O)kC[e4
} CY<,p$
} ?*tb|AL(R
} w q% 4'(
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 `s Az1/N
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类写好了,下面是在JSP中如下调用。 ^EPM~cEY\
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<% Mp:tcy,*
CountBean cb=new CountBean(); [ft#zxCJ
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); SYOND>E
CountCache.add(cb); $o?Wum
out.print(CountCache.list.size()+"<br>"); cP''
CountControl c=new CountControl(); Q?B5@J
c.run(); Ig-9Y;hdmn
out.print(CountCache.list.size()+"<br>"); N X4!G>v
%>