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: 1 P!Yxeh
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CountBean.java CmoE_8U>
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/* {C N~S*m
* CountData.java Tq[kl'_
* 2OVRf0.R~
* Created on 2007年1月1日, 下午4:44 EZ`te0[
* 6"&6`f
* To change this template, choose Tools | Options and locate the template under hFy;ffs.
* the Source Creation and Management node. Right-click the template and choose %UERc{~o*,
* Open. You can then make changes to the template in the Source Editor. :Ra,Eu
*/ `3WFjU5a
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package com.tot.count; %|q>pin2
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/** !u[eaLxV
* (jRm[7H
* @author ,NyY>~+
*/ QLiu2U o
public class CountBean { tnN.:%mZ
private String countType; B][U4WJ)
int countId; 3 09hn
/** Creates a new instance of CountData */ BMG3|N^
public CountBean() {} Vy Xhl;
public void setCountType(String countTypes){ lJ}_G>GJ
this.countType=countTypes; -~v2BN/
} c]n1':FT"
public void setCountId(int countIds){ `tA"
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this.countId=countIds; W_\5nF
} ;RC{<wBTx
public String getCountType(){ = C8 ?M
return countType; K<SyC54
} v4`"1Ss,K
public int getCountId(){ Mb|a+,:>3
return countId; emqZztccZ
} g9}DnCT*.
} p6#g;$V$
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CountCache.java |y!=J$$_H
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/* diL+:H
* CountCache.java l1OE!W W
* ao1(]64X"
* Created on 2007年1月1日, 下午5:01 e,vvzso
* %et }A93
* To change this template, choose Tools | Options and locate the template under Wz49i9e+d
* the Source Creation and Management node. Right-click the template and choose &_dt>.
* Open. You can then make changes to the template in the Source Editor. 4:$4u@
*/ eg\v0Y!rI
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package com.tot.count; }Gz~nf%
import java.util.*; ;c-(ObSm
/** |:q=T
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* DCIxRPw
* @author "7'J&^|
*/ ZkRx1S"m
public class CountCache { /YP{,#p
public static LinkedList list=new LinkedList(); "}u.v?HYz
/** Creates a new instance of CountCache */ 3G,Oba[$<
public CountCache() {} 8uc1iB
public static void add(CountBean cb){ v5!d$Vctu
if(cb!=null){ X$
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list.add(cb); w28o}$b`
} jVv0ST*z
} jSh5!6O
} |oH,
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CountControl.java 3oGt3F{gZ
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/* -BrMp%C
* CountThread.java q8X feoUV
* PWaw]*dFmy
* Created on 2007年1月1日, 下午4:57 >BIMi^
* T6O::o6
* To change this template, choose Tools | Options and locate the template under Y_;#UU689
* the Source Creation and Management node. Right-click the template and choose 3m]4=
* Open. You can then make changes to the template in the Source Editor. XX7{-Yy
*/ 8##-EN;ag
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package com.tot.count; I
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import tot.db.DBUtils; _X^1IaL
import java.sql.*; =)M/@T
/** !o5
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* 2 Wt> Mi
* @author 0LPig[
*/ PlU*X8
public class CountControl{ .f*4T4eR-
private static long lastExecuteTime=0;//上次更新时间 *rM^;4Zt
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 WKts[Z
/** Creates a new instance of CountThread */ (7mAt3n
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public CountControl() {} p#01gB
public synchronized void executeUpdate(){ ~ZmN44?R
Connection conn=null; #X%~B'
PreparedStatement ps=null; j#X.KM
try{ 6_J$UBT
conn = DBUtils.getConnection(); }\z.)B4,
conn.setAutoCommit(false); oiF}?:7Q7
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); X\]L=>]C
for(int i=0;i<CountCache.list.size();i++){ :}Xll#.,m
CountBean cb=(CountBean)CountCache.list.getFirst(); NTdixfR
CountCache.list.removeFirst(); Upc+Ukw
ps.setInt(1, cb.getCountId()); :Ux?,
ps.executeUpdate();⑴ .R)D3NZp
//ps.addBatch();⑵ %zA;+s$l
} KX76UW
//int [] counts = ps.executeBatch();⑶ @E;=*9ek{u
conn.commit(); 1{r3#MVL
}catch(Exception e){ S/}2; \Xm
e.printStackTrace(); i'a?kSy
} finally{ 8qY79)vD4E
try{ DwaBdN[!7
if(ps!=null) { Keuf9u
ps.clearParameters(); X>d"]GD
ps.close(); x^HGVWw_
ps=null; qOe+ZAJ{%N
} w&$`cD
}catch(SQLException e){} y[`l3;u:'
DBUtils.closeConnection(conn); J,V9k[88
} !g?|9
} V[{6e
public long getLast(){ '[U8}z3
return lastExecuteTime; dq7x3v^"ZG
} !2 LCLN\
public void run(){ EqyeJq .
long now = System.currentTimeMillis(); DQNnNsP:M-
if ((now - lastExecuteTime) > executeSep) { o]+z)5zC
//System.out.print("lastExecuteTime:"+lastExecuteTime); R%Qf7Q
//System.out.print(" now:"+now+"\n"); )hd@S9Z.Y
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ks3`3q 7
lastExecuteTime=now; g$7{-OpB
executeUpdate(); Fw/6?:C}O6
} k>F'ypm
else{ 6o
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//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); g'pK
} s8QMewU
} *meZ8DV2DH
} oeKHqP wg
//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\''e`Eb"5
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类写好了,下面是在JSP中如下调用。 p`mS[bxv!
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<% _,zA ^*b
CountBean cb=new CountBean(); 3b*cU}go
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); l*ayd>`~x
CountCache.add(cb); il}%7b-
out.print(CountCache.list.size()+"<br>"); 4FEk5D
CountControl c=new CountControl(); *Nw&_<\9Q
c.run(); +~'865 {
out.print(CountCache.list.size()+"<br>"); $u7;TW6QD
%>