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: c`_[q{(^m
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CountBean.java 2umgF
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/* :5BVVa0oR
* CountData.java QNgfvy
* 8{4jlL;"`?
* Created on 2007年1月1日, 下午4:44 }:hN}*H
* W(,3j{d2i
* To change this template, choose Tools | Options and locate the template under 5}"9)LT@@w
* the Source Creation and Management node. Right-click the template and choose NuC+iC$_/
* Open. You can then make changes to the template in the Source Editor. {:c5/
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*/ |#`qP^E
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package com.tot.count;
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/** vAjvW&'g
* (E]q>'X
* @author |tuh/e@dx
*/ |'N)HH>;
public class CountBean { bGe@yXId5
private String countType; .V`N^H:l
int countId; o0:RsODl
/** Creates a new instance of CountData */ MI\35~JAN
public CountBean() {} {#4F}@Q
public void setCountType(String countTypes){ fy|$A@f
this.countType=countTypes; x3Ze\N8w
} &-hXk!A
public void setCountId(int countIds){ ^K'@W
this.countId=countIds; [e;c)XS[
} zM2_z
public String getCountType(){ 8a3h)R
return countType; 6h:2,h
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} Av_JcH
public int getCountId(){ 7HM%Cd
return countId; 7FGi+
} .I
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} _%:$sAj
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CountCache.java k}FmdaPI'
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/* |!E: [UH
* CountCache.java JBt2R=
* $bsD'Io
* Created on 2007年1月1日, 下午5:01 S>V+IKW;(
* I> BGp4 AQ
* To change this template, choose Tools | Options and locate the template under T?HW=v_a
* the Source Creation and Management node. Right-click the template and choose }YCpd )@
* Open. You can then make changes to the template in the Source Editor. 0<#>LWaM_
*/ GYwU3`{
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package com.tot.count; FDCc?>,o
import java.util.*; On-zbE
/** `R6dnbH
*
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* @author jiqE^j3;
*/ ! N'HL-oT
public class CountCache { sFV&e->AN\
public static LinkedList list=new LinkedList(); xTg=oq
/** Creates a new instance of CountCache */ N`et]'_A}
public CountCache() {} 5L\&"['
public static void add(CountBean cb){ "kd)dy95H
if(cb!=null){ " `FcW
list.add(cb); jIi:tO9G^,
} x7ZaI{
} yXT8:2M
} #.j}:
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CountControl.java 7]H<ou
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/* w;;9YFBdM
* CountThread.java 6W[~@~D=
* g0ks[ }f-
* Created on 2007年1月1日, 下午4:57 XR|U6bf]
* ApNS0
* To change this template, choose Tools | Options and locate the template under 3t9Weo)
* the Source Creation and Management node. Right-click the template and choose .C,D;T{
* Open. You can then make changes to the template in the Source Editor. `Vl9/IEk
*/ YJu~iQ`i
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package com.tot.count; SNtk1pG>
import tot.db.DBUtils; 5Deo}(3
import java.sql.*; ez<V
/** 0TWd.+
* g5:?O,?
* @author 'S%H"W\
*/ 5.d[C/pRw
public class CountControl{ sOVU>tb\'
private static long lastExecuteTime=0;//上次更新时间 -}(2}~{e(
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 l}SHR|7<
/** Creates a new instance of CountThread */ o3YW(%cYR
public CountControl() {} C?j:+
public synchronized void executeUpdate(){ @2g
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Connection conn=null; hjD%=Ri0Z
PreparedStatement ps=null; gVNoC-n)
try{ F.),|t$\
conn = DBUtils.getConnection(); ;2 P
conn.setAutoCommit(false); bEm9hFvd
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); nvQTJ4,,
for(int i=0;i<CountCache.list.size();i++){ LhRd0
CountBean cb=(CountBean)CountCache.list.getFirst(); LwYWgT\e
CountCache.list.removeFirst(); :g ~_
ps.setInt(1, cb.getCountId()); 3 3zE5vr
ps.executeUpdate();⑴ h:RP/0E
//ps.addBatch();⑵ y9b%P]i
} <*(^QOM
//int [] counts = ps.executeBatch();⑶ l];/,J^
conn.commit(); niqknqW<t
}catch(Exception e){ $*;`$5.x^
e.printStackTrace(); "+E\os72|
} finally{ P ; h8
try{ ?N^1v&Q
if(ps!=null) { ?4^ 0xGyE
ps.clearParameters(); +z4E:v
ps.close(); &`oybm-p(
ps=null; h4#'@%
} McpQ7\*h
}catch(SQLException e){} dci<Rz`h
DBUtils.closeConnection(conn); 5th?m>
} [ ou$*
} 7=%Oev&0g-
public long getLast(){ kH8/8
return lastExecuteTime; k.z(.uc=
} Y_K W9T_
public void run(){ NSM7n=
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long now = System.currentTimeMillis(); @VPmr}p:{
if ((now - lastExecuteTime) > executeSep) { Yt?]0i+
//System.out.print("lastExecuteTime:"+lastExecuteTime); P0pBR_:o
//System.out.print(" now:"+now+"\n"); F$bV}>-1k
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); P ^ 4 @
lastExecuteTime=now; C;j&Vbf
executeUpdate(); stUUez>
} &d0sv5&s
else{ 4jt(tZS
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); v&bG`\ !
} oKb"Ky@s
} T+^c=[W
} -We9
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//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 HItNd
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类写好了,下面是在JSP中如下调用。 v2_` iwE
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<% 6tFi\,)E
CountBean cb=new CountBean(); ,J8n}7aI
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ^qnmKA>"F
CountCache.add(cb); m7DKC,
out.print(CountCache.list.size()+"<br>"); "Kdn`zN{
CountControl c=new CountControl(); G;$;$gM
c.run(); 'qvj[lpGr
out.print(CountCache.list.size()+"<br>"); ?w+ V:D
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