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: Ln
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CountBean.java Bu7A{DRf
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/* luW
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* CountData.java h ZoC _\
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* Created on 2007年1月1日, 下午4:44 p1Q/g Il
* MWM
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* To change this template, choose Tools | Options and locate the template under |]^l^e6m
* the Source Creation and Management node. Right-click the template and choose R=`U 4Ml;
* Open. You can then make changes to the template in the Source Editor. 0/ut:RV0
*/ SK's!m:r=
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package com.tot.count; <u0*"
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/** y:Z$LmPc<
* z{%oJ_
* @author \WWG>OUh.U
*/ z4CJn[m9
public class CountBean { BS N6|W
private String countType; aT&t_^[]
int countId; GF&_~48GD
/** Creates a new instance of CountData */ XmP;L(wa
public CountBean() {} S#,+Z7
public void setCountType(String countTypes){ F
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this.countType=countTypes; xXO RIlD
} iwUv`>l&
public void setCountId(int countIds){ PmHd9^C
this.countId=countIds; ]de\i=?|
} FIH@2zA
public String getCountType(){ WPIZi[hBs
return countType; &9RH}zv6
} ^Sw2xT$p{j
public int getCountId(){ +6
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return countId; RF:04d
} Ddb-@YD&+0
} mxgqS=`
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CountCache.java L${m/@9
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/* IAYACmlN&
* CountCache.java ]a M-p@
* ((qGh>*
* Created on 2007年1月1日, 下午5:01 }"hW b(
* ]
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* To change this template, choose Tools | Options and locate the template under >
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* the Source Creation and Management node. Right-click the template and choose M;qBDT~)
* Open. You can then make changes to the template in the Source Editor. I`NUurQTX
*/ ?z3]
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package com.tot.count; P/G>/MD/l
import java.util.*; GLCAiSMz[
/** rkq#7
* RB[/q:
* @author [_V:)
*/ ul$,q05nb
public class CountCache { 6(Vhtr2(*
public static LinkedList list=new LinkedList(); J smB^
/** Creates a new instance of CountCache */ ~T%Ui#Gc
public CountCache() {} H;QA@tF>5
public static void add(CountBean cb){ Pubv$u2
if(cb!=null){ q(gjT^aN
list.add(cb); j1A|D
} pl|h>4af
} 9p4y>3
} X &D{5~qC
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CountControl.java GV5qdD(
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/* ytiyF2Kp
* CountThread.java o,1Dqg4P3
* z3W3=@
* Created on 2007年1月1日, 下午4:57 ET. dI.R8
* hCAZ{+`z
* To change this template, choose Tools | Options and locate the template under KzNm^^#/$A
* the Source Creation and Management node. Right-click the template and choose { D+Ym%n
* Open. You can then make changes to the template in the Source Editor. w.z<60%},0
*/ ~@D/A/|
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package com.tot.count; 5rloK"
import tot.db.DBUtils; RJhK$\
import java.sql.*; ?`H[u7*%
/** E=]]b;u-n
* et` 0Je
* @author QD$Gw-U-l=
*/ FAw1o
public class CountControl{ hO
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private static long lastExecuteTime=0;//上次更新时间 s1bU
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 g5Hr7Km
/** Creates a new instance of CountThread */ /OG zt
public CountControl() {} R&*@@F-dx
public synchronized void executeUpdate(){ {n&Uf{
Connection conn=null; k3>YBf`fC
PreparedStatement ps=null; H O*YBL
try{ [9AM\n>g
conn = DBUtils.getConnection(); F?BS717qS%
conn.setAutoCommit(false); <( EyXV
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); wt?o
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for(int i=0;i<CountCache.list.size();i++){ D:9
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CountBean cb=(CountBean)CountCache.list.getFirst(); Q+'nw9:;T
CountCache.list.removeFirst(); UV@0gdy[
ps.setInt(1, cb.getCountId()); #K4*6LI
ps.executeUpdate();⑴ [Gtb+'8
//ps.addBatch();⑵ O,'#C\
} E7`qmn
//int [] counts = ps.executeBatch();⑶ 64umul
conn.commit(); ]Lm'RlV
}catch(Exception e){ C6]OAUXy:F
e.printStackTrace(); $gvr
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} finally{ ?:uNN
try{ VD[pZ2;4
if(ps!=null) { v+6e;xl8
ps.clearParameters();
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ps.close(); :G=FiC
ps=null; t7*#[x)a
} ^~1<f1(
}catch(SQLException e){} wd+K`I/v7h
DBUtils.closeConnection(conn); I 8zG~L%"
} hqDqt"dKz
} }`_(<H
public long getLast(){ 2 hq\n<
return lastExecuteTime; cP rwW6
} tJ'iX>9I
public void run(){ (s&&>M]r_
long now = System.currentTimeMillis(); ?JXa~.dA
if ((now - lastExecuteTime) > executeSep) { UQPU"F7.
//System.out.print("lastExecuteTime:"+lastExecuteTime); 5jZiJw(
//System.out.print(" now:"+now+"\n"); E ]f)Os$
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 1m)M;^_
lastExecuteTime=now; [>Fm[5x
executeUpdate(); _ck[&Q
} xaW{I7FfG
else{ i=rH7k
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); .<YcSG
} 8@eOTzm
} +>tUz D
} Fr [7
//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 ;gB`YNL
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类写好了,下面是在JSP中如下调用。 rQr!R$t/[
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<% Z
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CountBean cb=new CountBean(); 3CZS)
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 6gU{(H
CountCache.add(cb); "#4dW 7E
out.print(CountCache.list.size()+"<br>"); sn{tra
CountControl c=new CountControl(); Mu&x_&|
c.run(); fk{0d
out.print(CountCache.list.size()+"<br>"); m4m<nnM
%>