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: S>7Zq5*
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CountBean.java Pi6C1uY6
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/* e#k9}n^+
* CountData.java bl\44VK2'
* xtjTU;T
* Created on 2007年1月1日, 下午4:44 pooi8" G
* q9qmz[
* To change this template, choose Tools | Options and locate the template under ,$3
* the Source Creation and Management node. Right-click the template and choose <Q=ES,M
* Open. You can then make changes to the template in the Source Editor. ~0?p @8
*/ {549&]/o
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package com.tot.count; o<-%)#e
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/** &+`l
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* ?OKm~ Ek
* @author "<6pp4*I
*/ Wnl8XHPn
public class CountBean { GMU<$x8o
private String countType; uGl0z79
int countId; `ea$`2
/** Creates a new instance of CountData */ z$G?J+?J
public CountBean() {} Kggf!\MR8
public void setCountType(String countTypes){ .mDqZOpf=4
this.countType=countTypes; |]A{8BBC
} 8<P $E!
public void setCountId(int countIds){ 8)rv.'A((E
this.countId=countIds; -7ct+3"J
} mkBQX
public String getCountType(){ `P/* x[?
return countType; q~trn'X>
} Dr`\
public int getCountId(){ R)cns7oW
return countId; SX^fh.
} a\}|ikiE
} DHt 8 f
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CountCache.java Tc:W=\ <
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/* . F#mT h
* CountCache.java 77i |a]Kd
* kTiQO2H
* Created on 2007年1月1日, 下午5:01 @hzQk~Gdi
* H.idL6*G
* To change this template, choose Tools | Options and locate the template under `r*6P^P
* the Source Creation and Management node. Right-click the template and choose CI{]o&Tf
* Open. You can then make changes to the template in the Source Editor. HC{|D>x.
*/ a
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package com.tot.count; *~!xeL
import java.util.*; <Dm6CH
/** 7v,>sX
* +"3eh1q[
* @author V2 VsJ
*/ sF+0v p
public class CountCache { 7Wb.(` a<
public static LinkedList list=new LinkedList(); nNhN:?
/** Creates a new instance of CountCache */ =~=/ d q
public CountCache() {} ,xD{A}}V
public static void add(CountBean cb){ ,Qyz2-
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if(cb!=null){ k 5 "3*
list.add(cb); ]3={o3[:
} ,dVCbAS@
} tB_ V%qH
} :m&`bq
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CountControl.java l42m81x"
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/* 'R,d?ikY
* CountThread.java On'3K+(_
* 2M&4]d
* Created on 2007年1月1日, 下午4:57 xZ@Y`2A':
* Z$ftG7;P0
* To change this template, choose Tools | Options and locate the template under ='VIbE@qC
* the Source Creation and Management node. Right-click the template and choose 'oT}jI
* Open. You can then make changes to the template in the Source Editor. e-e{-pB6
*/ ]#BXaBVMY
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package com.tot.count; Xx'>5d>
import tot.db.DBUtils; Tb y+Pd;
import java.sql.*; (VO Ka
/** k oHY
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* dlT\VWMha(
* @author ^1~/FU
*/ vj^UF(X
public class CountControl{ '|d (<.[
private static long lastExecuteTime=0;//上次更新时间 Nb];LCx
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 o[v`Am?v
/** Creates a new instance of CountThread */ zr[~wM
public CountControl() {} '^/E2+
public synchronized void executeUpdate(){ ~zm/n,Epb
Connection conn=null; hf?^#=k^
PreparedStatement ps=null; cw5YjQ8 9
try{ %'=oMbi>i4
conn = DBUtils.getConnection(); he+[
conn.setAutoCommit(false); M:I,j
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); cbwzT0
for(int i=0;i<CountCache.list.size();i++){ J,D{dYLDD
CountBean cb=(CountBean)CountCache.list.getFirst(); ttsB'|ps
CountCache.list.removeFirst(); `+f\Q2]Z
ps.setInt(1, cb.getCountId()); Vks,3$
ps.executeUpdate();⑴ QE #$bCw
//ps.addBatch();⑵ N )!v-z,k
} +.N;h-'
//int [] counts = ps.executeBatch();⑶ 6AwnmGL(;;
conn.commit(); X*JD
}catch(Exception e){ e`~q;?:
e.printStackTrace(); :_aY:`
} finally{ ^=W&p%Y(!
try{ :9`1bZ?a
if(ps!=null) { p|FX_4RjX
ps.clearParameters(); PaDT)RrEM
ps.close(); <Z__Q
ps=null; ib&qH_r/
} vJCL
m/}*
}catch(SQLException e){} L_.}z)S[\
DBUtils.closeConnection(conn); 'pe0Q-
} 7 %|>7
} up1aFzY|6x
public long getLast(){ AO]lXa
return lastExecuteTime; qnS7z%H8
} r{TNPa6!
public void run(){ ,9pi9\S
long now = System.currentTimeMillis(); CC09:L?
if ((now - lastExecuteTime) > executeSep) { d+;wDu
//System.out.print("lastExecuteTime:"+lastExecuteTime); dXDD/8E
//System.out.print(" now:"+now+"\n"); IW1\vfe
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); P
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lastExecuteTime=now; `o3d@Vc
executeUpdate(); -Q@d
} &7W6IM
else{ p)jxqg
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 2G-?
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} h|H;ZC(B
} sWC"^ S o
} ;MMFF {
//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 ^~aSrREo
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类写好了,下面是在JSP中如下调用。 bVx]r[
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<% \nHlI=!P
CountBean cb=new CountBean(); #TWc` 8
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); LC7LO
CountCache.add(cb); LF~#4)B
out.print(CountCache.list.size()+"<br>"); X^W>
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CountControl c=new CountControl(); ^pjez+
c.run(); 3k<#;(
out.print(CountCache.list.size()+"<br>"); ]]Z,Qu#<-
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