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: j HT2|VGb*
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CountBean.java Ju$vuEO
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/* z.f~wAT@<
* CountData.java f`X#1w9
* m/"\+Hv
* Created on 2007年1月1日, 下午4:44 Z9rs,_A
* Zy2@1-z6
* To change this template, choose Tools | Options and locate the template under i"uAT$x e
* the Source Creation and Management node. Right-click the template and choose gk+$CyjJ
* Open. You can then make changes to the template in the Source Editor. v4}kmH1
*/ pb~&gliW
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package com.tot.count; pPcn
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t
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/** <$s G]l!\
* 8$!/Zg
* @author QE7
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*/ {q2H_H
public class CountBean { Z']D8>d
private String countType; v>TI.;{y
int countId; ruM16*S{=
/** Creates a new instance of CountData */ ``o:N`
public CountBean() {} yi3@-
public void setCountType(String countTypes){ [o)P
this.countType=countTypes; c?L_n=B
} 5B{O!SNd
public void setCountId(int countIds){ =4
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this.countId=countIds; MT" 2^&R
} -`6O(he
public String getCountType(){ Ue|]M36
return countType; zzfwI@4
} 4NxtU/5-sU
public int getCountId(){ IEV3(qzt
return countId; B[F,D
} LQSno)OZ
} 3`4g*wO
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CountCache.java sbOa]
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/* @*W,Jm3Y
* CountCache.java 6.|f iQs]
* `P9vZR;
* Created on 2007年1月1日, 下午5:01 v"Bv\5f,Ys
* w}pFa76rm
* To change this template, choose Tools | Options and locate the template under NS"hdyA
* the Source Creation and Management node. Right-click the template and choose O&]Y.Z9,A
* Open. You can then make changes to the template in the Source Editor. MId\dFu
*/ 6sl*Ko[
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package com.tot.count; ymybj
import java.util.*; ~DcX}VCm
/** u D_|/ (
* &O(z|-&| x
* @author \}t(g}7T
*/ Y+ P\5G
public class CountCache { oQ@X}6B%S
public static LinkedList list=new LinkedList(); #X7fs5$&
/** Creates a new instance of CountCache */ j2" jCv
public CountCache() {} ~q#UH'=%
public static void add(CountBean cb){ +2`RvQN
if(cb!=null){ 98bmia&H
list.add(cb); z=vfP%
} d}%GHvOi
} f;#hcRSH
} N5[QQtQ
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CountControl.java -uN5DJSW
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/* z^S=ji U++
* CountThread.java *nU7v3D
* +LV~%?W
* Created on 2007年1月1日, 下午4:57 ~j",ePl
* i;`rzsRb
* To change this template, choose Tools | Options and locate the template under $Ne$s
* the Source Creation and Management node. Right-click the template and choose F))+a&O
* Open. You can then make changes to the template in the Source Editor. &H;0N"Fn
*/ 828E^Q"<
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package com.tot.count; +j&4[;8P:
import tot.db.DBUtils; #0"Fw$Pc
import java.sql.*; \kZxys!4
/** JadXd K=gE
* z'3
* @author G/\t<>O8o
*/ 6",1JH,;p
public class CountControl{ 6;9SU+/
private static long lastExecuteTime=0;//上次更新时间 `Q^G
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private static long executeSep=60000;//定义更新间隔时间,单位毫秒 {LVii}<
/** Creates a new instance of CountThread */ *xA&t)z(i
public CountControl() {} wqJ^tA!
public synchronized void executeUpdate(){ su>GeJiPW
Connection conn=null; i]a0
"
PreparedStatement ps=null; <H`&Zqqk
try{ _CDUUr
conn = DBUtils.getConnection(); m^@,0\F
conn.setAutoCommit(false); )t{?7wy
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); E$=!l{Ms
for(int i=0;i<CountCache.list.size();i++){ yYwZZa1
CountBean cb=(CountBean)CountCache.list.getFirst(); *KN ' 0Z@W
CountCache.list.removeFirst(); Z{xm(^'i
ps.setInt(1, cb.getCountId()); M%5qx,JQY
ps.executeUpdate();⑴ AK%`EsI^
//ps.addBatch();⑵ 7RM$%'n\
} CWdA8)n.
//int [] counts = ps.executeBatch();⑶ F\F_">5
conn.commit(); K[PH#dF5,x
}catch(Exception e){ A
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e.printStackTrace(); [U.3rcT"N
} finally{ <43O,Kx'Su
try{ URdCV{@42
if(ps!=null) { s'qd%JxD
ps.clearParameters(); n=WwB(}q
ps.close(); ?8X;F"Ba
ps=null; -61{ MMiA
} @{3$H^
}catch(SQLException e){} SB0Cq
DBUtils.closeConnection(conn); 109dB$+$
} \/J>I1J
} ZpvURp,I
public long getLast(){ $OB 2ZS"
return lastExecuteTime; uOUgU$%zqH
} `w';}sQA7
public void run(){ g|ewc'y
long now = System.currentTimeMillis(); ~x^E kE
if ((now - lastExecuteTime) > executeSep) { `dekaRo
//System.out.print("lastExecuteTime:"+lastExecuteTime); Ndq/n21j
//System.out.print(" now:"+now+"\n"); ~o_0RB
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); O?5uCh$H
lastExecuteTime=now; IA I!a1e!
executeUpdate(); wd*8w$\
} CC&o pC
else{ 'ol8l Ia.P
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 'Dw+k;RH
} _W]R|kYl$'
} ~SUrbRaY>
} Y1fcp_]m
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 ;]c@%LX
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类写好了,下面是在JSP中如下调用。 Pt< JF
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<% G#yv$LY#
CountBean cb=new CountBean(); %d?.v_Hu0
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); XzLB#0
CountCache.add(cb); ^f6pw!
out.print(CountCache.list.size()+"<br>"); 3{c6)vR2
CountControl c=new CountControl(); xb{G:v
c.run(); j=|cx+nb
out.print(CountCache.list.size()+"<br>"); En!X}Owh
%>