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: P?h1nxm`'
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CountBean.java ,>-D xS
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/* 27D*FItc
* CountData.java g3$'Ghf
* =
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* Created on 2007年1月1日, 下午4:44 x
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* ez'NHodwk2
* To change this template, choose Tools | Options and locate the template under MV" n{1B
* the Source Creation and Management node. Right-click the template and choose d%8n
* Open. You can then make changes to the template in the Source Editor. %b^4XTz
*/ wSjDa.?'
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package com.tot.count; 7~XC_Yc1
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/**
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* {6ZSf[Y6B
* @author j9h/`Bn
*/ 0DicrnH8
public class CountBean { wb.yGfJ
private String countType; _aFe9+y
int countId; RK!9(^Ja
/** Creates a new instance of CountData */ 0V~zZ/e
public CountBean() {} 64?HqO
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public void setCountType(String countTypes){ "bhK%N;
this.countType=countTypes; Nnh\FaI
} [K3
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public void setCountId(int countIds){ e v$:7}h=
this.countId=countIds; Ku,wI86
} dun`/QKV
public String getCountType(){ u4Nh_x8\Nr
return countType;
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} @Y/&qpo$#W
public int getCountId(){ 2#.s{ Bv
return countId; /yG7!k]Eg
} 12Oa_6<\0;
} m%[e_eS
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CountCache.java *K|~]r(F?
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/* >_2~uF@pb
* CountCache.java ;TJpD0
* n*7^lAa2
* Created on 2007年1月1日, 下午5:01 O{l4 f:51
* zTa5N
* To change this template, choose Tools | Options and locate the template under So&gDR;b
* the Source Creation and Management node. Right-click the template and choose /"Vd( K2Z
* Open. You can then make changes to the template in the Source Editor. r%=-maPL[
*/ i{6&/TBnr
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package com.tot.count; \|0z:R;X
import java.util.*; yu'-'{%
/** 4Im>2)
* -hXKCb4YU
* @author T aS1%(
*/ F{ %*(U
public class CountCache { @U_CnhPQq
public static LinkedList list=new LinkedList(); ef`_
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/** Creates a new instance of CountCache */ n2K1X!E$
public CountCache() {} d=vuy
public static void add(CountBean cb){ G<7M;vRvP
if(cb!=null){ f}bq
list.add(cb); r84^/+"T
} ~lo43$)^
} 60~;UBm5O
} ~,}|~
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CountControl.java Vc9rc}
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/* MZV$YD^S
* CountThread.java lKsn6c,]
* =@!t/LR7kg
* Created on 2007年1月1日, 下午4:57
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* kO\ O$J^S
* To change this template, choose Tools | Options and locate the template under WutPy_L<
* the Source Creation and Management node. Right-click the template and choose 6nL^"3@S!
* Open. You can then make changes to the template in the Source Editor. 9rMO=
*/ 01'>[h#_n
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package com.tot.count; ]CzK{-W
import tot.db.DBUtils; u#Ig!7iUu
import java.sql.*; zr|DC] 3
/** PLkS-B
* i47LX;}
* @author zP,r,ok7
*/ '{ _ X1
public class CountControl{ \\R}3 >Wc
private static long lastExecuteTime=0;//上次更新时间 AXlVH%'
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 S~3|1Hw*tN
/** Creates a new instance of CountThread */ Rge>20uTl$
public CountControl() {} Rf!v{\
public synchronized void executeUpdate(){ UH MJ(.Wa-
Connection conn=null; |,$&jSe
PreparedStatement ps=null; N6._Jb
try{ %+l95Dv1
conn = DBUtils.getConnection(); )k Wxp
conn.setAutoCommit(false); )95k3xo
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); q\@Zf}
for(int i=0;i<CountCache.list.size();i++){ yUnV%@.
CountBean cb=(CountBean)CountCache.list.getFirst(); 7W)W9=&BT
CountCache.list.removeFirst(); :(A&8<}-6
ps.setInt(1, cb.getCountId()); q}Q G<%VR
ps.executeUpdate();⑴ G!Brt&_'
//ps.addBatch();⑵ G=zNZ
} vclc%ws
//int [] counts = ps.executeBatch();⑶ (p5q MP]L
conn.commit(); b&P)J|Fe
}catch(Exception e){ bny5e:= d
e.printStackTrace(); *\XOQWrF
} finally{ >Hnm.?-AWl
try{ V[(fE=cIN~
if(ps!=null) { f]r*;YEc4
ps.clearParameters(); c]{}|2u
ps.close(); 67(s\
ps=null; {IgH0+z
} V*@aE
}catch(SQLException e){} 5REFz
DBUtils.closeConnection(conn); j,.M!q]
} M=raKb?F
} 4 eLZ
public long getLast(){ 1b3 a(^^E
return lastExecuteTime; DKjiooD
} 9E ^!i
public void run(){ g[(@@TiG
long now = System.currentTimeMillis(); .aT@'a{F
if ((now - lastExecuteTime) > executeSep) { K;6#v%
//System.out.print("lastExecuteTime:"+lastExecuteTime); ':(AiD -}
//System.out.print(" now:"+now+"\n"); :GIBB=D9
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); gkd4)\9
lastExecuteTime=now; gk|>E[.
executeUpdate(); m8L *LB
} KM;H '~PZi
else{ ,1{qZ(l1
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); a]r+np]vTy
} t)&U'^
} 3Z";a
} o4" [{LyT
//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 g!}]FQBb
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类写好了,下面是在JSP中如下调用。 8H4NNj Oy
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<% @/:4beh
CountBean cb=new CountBean(); 4NID:<
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); %4nf(|8n
CountCache.add(cb);
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out.print(CountCache.list.size()+"<br>"); zu1"`K3b
CountControl c=new CountControl();
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c.run(); 4z(~)#'^
out.print(CountCache.list.size()+"<br>"); b1?^9c#0d
%>