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<lp<{;
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CountBean.java i7x&[b
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/* 0~|0D#klB
* CountData.java (i
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* fSo8O
* Created on 2007年1月1日, 下午4:44 19 5_1?'<
* 0'^M}&zCi
* To change this template, choose Tools | Options and locate the template under <Q[%:LD
* the Source Creation and Management node. Right-click the template and choose 3Y#Q'r?
* Open. You can then make changes to the template in the Source Editor. `3TR`,=
*/ &l(T},-X
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package com.tot.count; H2X_WSwm
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/** )nUdU
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* _c5@)I~
* @author [2:d@=%.
*/ ym;]3<I?I[
public class CountBean { l*CulVX
private String countType; G[64qhTC
int countId; ,@*5x'auK
/** Creates a new instance of CountData */ rH}|~
public CountBean() {} $LP(\T([
public void setCountType(String countTypes){ Nr|Gw
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this.countType=countTypes; eI8o#4nT
} * #yF`_p
public void setCountId(int countIds){ x39tnf/F
this.countId=countIds; N,`@Q7
} h ldZA
public String getCountType(){ xP8/1wd.
return countType; mnt&!X4<
} %bcf% 7
public int getCountId(){ P`tOL#UeZL
return countId; pa-*&p
} D#GuF~-F!R
} R
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CountCache.java j{C~wy!J
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/* 6IqPZ{g9K'
* CountCache.java oodA&0{)d
* 3.Fko<D4jD
* Created on 2007年1月1日, 下午5:01 KOixFn1
* 7%h;To-<6
* To change this template, choose Tools | Options and locate the template under p$,7qGST
* the Source Creation and Management node. Right-click the template and choose ,xwiJfG;
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* Open. You can then make changes to the template in the Source Editor. 1P)K@j
*/ 175e:\Tw
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package com.tot.count; `zoHgn7B9q
import java.util.*; c |0p'EQ
/** (Mv~0ShakO
* P|NGAd
* @author 5BrN
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*/ V_i&@<J
public class CountCache { `E~"T0RX
public static LinkedList list=new LinkedList(); GcM1*)$ 4
/** Creates a new instance of CountCache */ :tWkK$
public CountCache() {} PYQ0&;z
public static void add(CountBean cb){ xM())Z|2
if(cb!=null){ "rdpA[>L
list.add(cb); f]*;O+8$LN
} enk`I$Xx
} )xp3
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} /qdv zv%T
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CountControl.java ximVh}'a
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/* A &}]:4@{
* CountThread.java tY$@,>2 v
* nJ2B*(S'v.
* Created on 2007年1月1日, 下午4:57 m mF0RNE
* p39$V[*g(
* To change this template, choose Tools | Options and locate the template under r'noB<|e
* the Source Creation and Management node. Right-click the template and choose 2)BO@]n
* Open. You can then make changes to the template in the Source Editor. fb Bu^]^S
*/ UVDMYA0
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package com.tot.count; 8Hq4ppC
import tot.db.DBUtils; IlJ"t`Z9)
import java.sql.*; kTjn%Sn,
/** ;X}2S!7Ko
* HOi~eX1d
* @author %XR(K@V
*/ 0MpW!|E[b
public class CountControl{ #x 6/"Y2
private static long lastExecuteTime=0;//上次更新时间 Up
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private static long executeSep=60000;//定义更新间隔时间,单位毫秒 m{oe|UVcmr
/** Creates a new instance of CountThread */ \: ZDY(>1
public CountControl() {} a3n
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public synchronized void executeUpdate(){ Aa-5k3:x]=
Connection conn=null; jd]L}%ax
PreparedStatement ps=null; v:lkvMq|=
try{ ",apO
conn = DBUtils.getConnection(); A":=-$)
conn.setAutoCommit(false); 7<LuL
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); YM#'+wl}`
for(int i=0;i<CountCache.list.size();i++){ "s@Hg1
CountBean cb=(CountBean)CountCache.list.getFirst(); "=2\kZ
CountCache.list.removeFirst(); 'qV lq5.
ps.setInt(1, cb.getCountId()); ESviWCh0Fl
ps.executeUpdate();⑴ 2fdN@iruB
//ps.addBatch();⑵ 9q ]f]S.L
} `*[Kmb\
//int [] counts = ps.executeBatch();⑶ PY|zN|
conn.commit(); ZQ"dAR/y
}catch(Exception e){ I484cR2.
e.printStackTrace(); mN-O{k0\
} finally{ +:Xg7H*
try{ e"1mdw"
if(ps!=null) { ^/%o
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ps.clearParameters(); wsdZwik
ps.close(); '*[7O2\%/
ps=null; &$ }6:
} MoxWnJy}
}catch(SQLException e){} 8K^#$,.."
DBUtils.closeConnection(conn); xlcCL?qQj
} i`YZ;L L
} G%Lt>5*!nE
public long getLast(){ TFldYKd/l
return lastExecuteTime; ~M7X]
} iwIn3R,
public void run(){ 3 85qQppz
long now = System.currentTimeMillis(); Cw^iA
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if ((now - lastExecuteTime) > executeSep) { foPM5+.G
//System.out.print("lastExecuteTime:"+lastExecuteTime); 8-gl$h
//System.out.print(" now:"+now+"\n"); lB2F09`
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); I3Co
lastExecuteTime=now; iTevl>p!
executeUpdate(); ipG 0ie+
} g3s5ra[
else{ ?i_2ueVR
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); Vuy%7H
} ka=A:biz
} 51%Rk,/o
} *s, bz.[
//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 nVlZ_72d
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类写好了,下面是在JSP中如下调用。 QlVj#Jv;~
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<% rhYAR r'
CountBean cb=new CountBean(); ` *hTx|!'
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); l_((3e[)
CountCache.add(cb); Vh01y f
out.print(CountCache.list.size()+"<br>"); W rT_7
CountControl c=new CountControl(); alxIc.[
c.run(); '"q+[zwv
out.print(CountCache.list.size()+"<br>"); Li8/GoJW-T
%>