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: RlU ?F
|9Yx`_DF
CountBean.java l-!"
KK]R@{ r
/* -nX{&Z3-s
* CountData.java dM19;R@4
* bY*_6SPK4
* Created on 2007年1月1日, 下午4:44 |id7@3leu
* 6#Y]^%?uy
* To change this template, choose Tools | Options and locate the template under <<Y]P+uU
* the Source Creation and Management node. Right-click the template and choose #pPR>,4
* Open. You can then make changes to the template in the Source Editor. E[=&6T4
*/ a?4Asn
~m0=YAlk?
package com.tot.count; e=IbEm{|
"LW\osjen
/** 'J!Gip ,
* yB=R7E7
* @author )8n?.keq
*/ w40*vBz
public class CountBean { B|+%ExT7
private String countType; yd'cLZd<}
int countId; B#.xs>{N
/** Creates a new instance of CountData */ M?hPlo"_
public CountBean() {} K`ygW|?gt
public void setCountType(String countTypes){ LWSy"Cs*
this.countType=countTypes; {{[@ X
} z|Xt'?9&n
public void setCountId(int countIds){ !=yO72dgLY
this.countId=countIds; ) te_ <W
} 0}'/p N>
public String getCountType(){ QwF.c28[
return countType; p]Qe5@NT
} V~5vR`}
public int getCountId(){ I$)9T^Ra
return countId; t\!5$P
} RZSEcRlN
} QJ>=a./
cIkA ~F
CountCache.java ^L
Xr4
D62'bFB^
/* f`\J%9U _O
* CountCache.java mUR[;;l
* ?duw0SZ
* Created on 2007年1月1日, 下午5:01 5GPAt
* Vhb~kI!x
* To change this template, choose Tools | Options and locate the template under F8{T/YhZ
* the Source Creation and Management node. Right-click the template and choose 66+]D4(k
* Open. You can then make changes to the template in the Source Editor. 9)j"|5H
*/ J4iu8_eH!D
<Nc9F['
package com.tot.count; \,:7=
import java.util.*; wLt0Fq6QG
/** Gz8JOl
* LUz`P6
* @author Pl#u,Y
*/ L=s8em]7l
public class CountCache { (5[#?_~
public static LinkedList list=new LinkedList(); 36.mf_AM
/** Creates a new instance of CountCache */ -(}N-yu
public CountCache() {} W&Xi&[Ux
public static void add(CountBean cb){ 3=UufI
if(cb!=null){ iU~d2R+
list.add(cb); <8Z%'C6d
} ~EYdE qS)
} w>Ft5"z
} |c-`XC2g
gB,Q4acjj
CountControl.java a"1LF`
miCY?=N`
/* 7Bf4ojKt
* CountThread.java o(t`XE['<
* &qa16bz
* Created on 2007年1月1日, 下午4:57 ZC^?ng
* *S4&V<W>
* To change this template, choose Tools | Options and locate the template under 6+PP(>em
* the Source Creation and Management node. Right-click the template and choose dPgA~~
* Open. You can then make changes to the template in the Source Editor. y6s/S.
*/ SxC(:k2b;
MzlE
package com.tot.count; +OB&PE
import tot.db.DBUtils; L9whgXD
import java.sql.*; ~IQjQz?
/** {z'Gg
* YsO`1D
* @author Rob:W|
*/ W^3'9nYU
public class CountControl{ W$Aypy
private static long lastExecuteTime=0;//上次更新时间 F{}:e QD
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 5pRVA
/** Creates a new instance of CountThread */ ;hFB]/.v
public CountControl() {} g)MLgjj
public synchronized void executeUpdate(){ o
i~,}E_
Connection conn=null; "DJ%Yo
PreparedStatement ps=null; r&L1jT.
try{ Vr&v:8:wb
conn = DBUtils.getConnection(); z:{R4#(Q
conn.setAutoCommit(false); tfe'].uT
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); A+3=OBpkW0
for(int i=0;i<CountCache.list.size();i++){ O9{A)b!HB
CountBean cb=(CountBean)CountCache.list.getFirst(); h 'is#X 6:
CountCache.list.removeFirst(); ^AUQsRA7PZ
ps.setInt(1, cb.getCountId()); #`"B
YFV[E
ps.executeUpdate();⑴ ;:Kc{B.s
//ps.addBatch();⑵ Mq6_Q07
} `]Vn[^?D
//int [] counts = ps.executeBatch();⑶ $,T3vX]<
conn.commit(); gJzS,g1]
}catch(Exception e){ i\MW'b
e.printStackTrace(); Yc(lY
N
} finally{ _ `7[}M~
try{ _)#~D*3
if(ps!=null) { D,uT#P
ps.clearParameters(); wp-3U}P2(
ps.close(); 23q2u6.F`
ps=null; `7',RUj|D
} _'s5FlZq
}catch(SQLException e){} \z2d=E
DBUtils.closeConnection(conn); dBW#PRg
} ['0^gN$:e
} IRI<no
public long getLast(){ |'#uV)b0@
return lastExecuteTime; uYc&Q$U
} Zo,]Dx
public void run(){ a+\s 0Qo<
long now = System.currentTimeMillis(); l02aXxT)]
if ((now - lastExecuteTime) > executeSep) { P$G|o|h
//System.out.print("lastExecuteTime:"+lastExecuteTime); W8!8/IZbN
//System.out.print(" now:"+now+"\n"); UAdj[m61
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); @{8805Dp
lastExecuteTime=now; sM%.=~AN
executeUpdate(); j !`2Z@
} zU};|Zw
else{ V0:db
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); u\UI6/
} jTY{MY Jh
} e?-LB
} ]PXpzruy
//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
(8j@+J
ve=
nh]N
类写好了,下面是在JSP中如下调用。 S'vUxOAo
HSk}09GV
<% .ZH5^Sv$vp
CountBean cb=new CountBean(); nL!nzA
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); c1_?Z
CountCache.add(cb); {*4Z9.2c*
out.print(CountCache.list.size()+"<br>"); TUVqQ\oF:
CountControl c=new CountControl(); s-xby~
c.run(); VnMiZAHR
out.print(CountCache.list.size()+"<br>"); ~9+\
%>