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: 5-"aK~@+
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CountBean.java m!:sDQn{3
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/* /z4n?&tM
* CountData.java @eRv`O"
* =2d h}8Mz
* Created on 2007年1月1日, 下午4:44 =]0AZ
* nb(Od,L
* To change this template, choose Tools | Options and locate the template under xUDXg*
* the Source Creation and Management node. Right-click the template and choose hJ(S]1B~G
* Open. You can then make changes to the template in the Source Editor. -aIB_
*/ zmU>
} BnPNc[I
package com.tot.count; / KxZ+Ww>v
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/** )IGx3+I
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* \`YV)"y" ~
* @author Bmi9U
*/ ^j7]> I
public class CountBean { $ !:xjb
private String countType; n<MreKixE
int countId; 4z,n:>oH
/** Creates a new instance of CountData */ v;IuB
public CountBean() {} Cx
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public void setCountType(String countTypes){ t<znz6
this.countType=countTypes; 5}`e"X
} tN&X1
public void setCountId(int countIds){ 4|KtsAVp{
this.countId=countIds; # |,c3$
} "@@Z{
public String getCountType(){ ` MXGEJF
return countType; P>ZIP*
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} X&.LX
public int getCountId(){ pAc "Wo(Q
return countId; $(;0;!t.
} L_}F.nbS5
} \rmge4`4
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CountCache.java *@[+C~U
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/* G0v<`/|>}
* CountCache.java 1#^r5E4
* NU!B|l
* Created on 2007年1月1日, 下午5:01 ]nQ(|$rW
* <k-hRs2d
* To change this template, choose Tools | Options and locate the template under LArfX,x3i
* the Source Creation and Management node. Right-click the template and choose ~bLhI
* Open. You can then make changes to the template in the Source Editor. `r.
*/ `rI[
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package com.tot.count; nWv6I&
import java.util.*; /SQ1i}%
/** uzWz+atH
* +U,>D+
* @author 5gY9D!;:0D
*/ <^wqN!/
public class CountCache { - x]gp5
public static LinkedList list=new LinkedList(); Ixv/xI
/** Creates a new instance of CountCache */ -gb'DN1BG
public CountCache() {} S$Fq1
public static void add(CountBean cb){ ^ot9Q
if(cb!=null){ "SN+ ^`
list.add(cb); VtJyE}
} i{6wns?KMj
} D^\2a;[AxA
} 2V =bE-
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CountControl.java ]$?\,`
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/* FK.Qj P:
* CountThread.java P};GcV-
* \x+ "1
* Created on 2007年1月1日, 下午4:57 ajALca4
* {A MoE+U
* To change this template, choose Tools | Options and locate the template under \9s x_T
* the Source Creation and Management node. Right-click the template and choose -87]$ ax
* Open. You can then make changes to the template in the Source Editor. 6T{SRN{
*/ z+%74O"c
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package com.tot.count; RT+_e
import tot.db.DBUtils; 5mB'\xGO2
import java.sql.*; 9U~sRj=D
/** $|r
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* 41jlfKiOm
* @author 2K$#U|Qi
*/ dNgjM
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public class CountControl{ L\("
private static long lastExecuteTime=0;//上次更新时间 :Y2J7p[+
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 sn.&|)?Fi
/** Creates a new instance of CountThread */ L64cCP*
public CountControl() {} X"3Za[9j
public synchronized void executeUpdate(){ X3,+aL`
Connection conn=null; Ld3!2g2y7&
PreparedStatement ps=null; "4e{Cq
try{ HrS
conn = DBUtils.getConnection(); 6$6Qk !%
conn.setAutoCommit(false); (w{C*iB
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); +2S#3m?1
for(int i=0;i<CountCache.list.size();i++){ TkSeDP
CountBean cb=(CountBean)CountCache.list.getFirst(); (k&r^V/=
CountCache.list.removeFirst(); 7T}r]C.
ps.setInt(1, cb.getCountId()); YN 31Lo
ps.executeUpdate();⑴ A J"/T+g_
//ps.addBatch();⑵ mY !LGN
} <<.%Gk
//int [] counts = ps.executeBatch();⑶ 7__?1n~{
conn.commit(); (GI]Uyn
}catch(Exception e){
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e.printStackTrace(); g?d*cwtU
} finally{ zCdzxb_h"
try{ >gLLr1L\
if(ps!=null) { N_),'2
ps.clearParameters(); Ig M_l=
ps.close(); F(#~.i
ps=null; O)Mf/P'
} m5rJY/
}catch(SQLException e){} J{bNx8.&
DBUtils.closeConnection(conn); #Bgq]6G2
} KK4"H]!.
} .WT^L2l%
public long getLast(){ kw.IVz<
return lastExecuteTime; hXx.
} ?\$\YX%/p
public void run(){
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long now = System.currentTimeMillis(); a#G]5TZ
if ((now - lastExecuteTime) > executeSep) { Ps_q\R
//System.out.print("lastExecuteTime:"+lastExecuteTime); S|?Ht61k
//System.out.print(" now:"+now+"\n"); %1jApCJ
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); Y94/tjt
lastExecuteTime=now; .a *^6TC.
executeUpdate(); j}$Up7pW
} @"E{gM@B
else{ >hbT'Or@
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); {#'M3z=
} V9Gk``F<RZ
} 'fkaeFzOl
} ie%_-
//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 lSk<euCYs
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类写好了,下面是在JSP中如下调用。 =YRN"
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<% SJdi*>
CountBean cb=new CountBean(); r9d dVD
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); t@O4!mFH
CountCache.add(cb); `DPR >dd@
out.print(CountCache.list.size()+"<br>"); ko%B`
CountControl c=new CountControl(); $ZOKB9QccC
c.run(); &`J?`l X
out.print(CountCache.list.size()+"<br>"); p>@S61
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%>