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: V-vlTgemwc
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CountBean.java %2yAvGa1
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/* elbG\qXBp
* CountData.java !A[S6-18%-
* c#\-%h
* Created on 2007年1月1日, 下午4:44 ac6*v49
* ~Fx&)kegTo
* To change this template, choose Tools | Options and locate the template under iVeQ]k(u
* the Source Creation and Management node. Right-click the template and choose ="B
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* Open. You can then make changes to the template in the Source Editor. .5g}rxO8
*/ 7c::Qf[|
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package com.tot.count; %3,xaVN
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/** $^Ca:duk
* /2h][zrZ[.
* @author G?[-cNdk
*/ BW71 s
public class CountBean { .Z5[_'T
private String countType; $Sb@zLi)
int countId; ;c)! @GoA
/** Creates a new instance of CountData */ @+dHF0aXd
public CountBean() {} oEAfowXSqk
public void setCountType(String countTypes){ ~V$ f#X
this.countType=countTypes; eycV@|6u*
} jYdV?B
public void setCountId(int countIds){ ;](h2Z`3s
this.countId=countIds; #>q[oie1e
} W uf/LKj
public String getCountType(){ 2v\W1VF
return countType; 9Dq.lr^
} U_*3>Q
public int getCountId(){ yqBa_XPV8
return countId; 2f`xHI/@fj
} >a9l>9fyY
} I Tn;m
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CountCache.java yiO31uQt
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/* 6J;i,/ky
* CountCache.java h,hL?imD
* 1(pjVz&
* Created on 2007年1月1日, 下午5:01 3k{c$x}
* L?.7\a@
* To change this template, choose Tools | Options and locate the template under lEa W7j
* the Source Creation and Management node. Right-click the template and choose >p |yf.G
* Open. You can then make changes to the template in the Source Editor. !VNbj\Bp
*/ O*4gV }:G
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package com.tot.count; 6JWGu/A
import java.util.*; U6a zhi&,
/** 1t%<5O;R
*
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* @author 7*g(@d
*/ .$^wy3:F"
public class CountCache { CLktNR(45
public static LinkedList list=new LinkedList(); c85O_J
/** Creates a new instance of CountCache */ r_=p,#}#
public CountCache() {} Fd}<Uote3
public static void add(CountBean cb){ sZEgsrJh
if(cb!=null){ gDj_KKd
list.add(cb); &@"w-M
} R
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} voH4
} 1)gv%_
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CountControl.java !*8#jy
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/* 3z$HKG
* CountThread.java /evaTQPz
* FSVS4mtiX\
* Created on 2007年1月1日, 下午4:57
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* 3f,u}1npa*
* To change this template, choose Tools | Options and locate the template under excrXx
* the Source Creation and Management node. Right-click the template and choose :SQLfOQ
* Open. You can then make changes to the template in the Source Editor. 6yp+h
*/ W'd/dKUx
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package com.tot.count; -P*xyI
import tot.db.DBUtils; ;h~?ko
import java.sql.*; LEA;dSf
/** &E`9>&~J
* GP Ix@k
* @author Q{8qm<0g
*/ 2!{N[*)
public class CountControl{ rEg+i@~
private static long lastExecuteTime=0;//上次更新时间 <gR`)YF7
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 E2-ojL[6
/** Creates a new instance of CountThread */ $u&|[vcP0
public CountControl() {} |O%:P}6c
public synchronized void executeUpdate(){ O<bDU0s{M
Connection conn=null; z,M'Tr.1|
PreparedStatement ps=null; n~9 i^
try{ nxD'r
conn = DBUtils.getConnection(); tb:
conn.setAutoCommit(false); _,t&C7Yf;
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); BjwMb&a;
for(int i=0;i<CountCache.list.size();i++){ $}V7(wu 6@
CountBean cb=(CountBean)CountCache.list.getFirst(); [Yn;G7cK
CountCache.list.removeFirst(); N*HH,m&
ps.setInt(1, cb.getCountId()); u1wg
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ps.executeUpdate();⑴ kz$(V(k<
//ps.addBatch();⑵ >QA/Mi~R
} 'G52<sF
//int [] counts = ps.executeBatch();⑶ 2(hvv-
conn.commit(); p EY>A_F
}catch(Exception e){ Q;=6ag'
e.printStackTrace(); #`r(zI[
} finally{ )K8P+zn~
try{ dEL3?-;'
if(ps!=null) { 5Zzr5WM
ps.clearParameters(); n#)PvV~
ps.close(); C0P*D,
ps=null; 2B5A!?~>
} S!u6dz^[$X
}catch(SQLException e){} ,9F*96
DBUtils.closeConnection(conn); jC#`PA3m=
} s bs[=LW4
} ;HR 6X
public long getLast(){ VjC*(6<Gj
return lastExecuteTime; 7 kEx48
} /A0 [_
public void run(){ :
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long now = System.currentTimeMillis(); P"oYC$
if ((now - lastExecuteTime) > executeSep) { wwo(n$!\
//System.out.print("lastExecuteTime:"+lastExecuteTime); j!6elzg
//System.out.print(" now:"+now+"\n"); n9N#&Q"7m
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); $+A%ODv
lastExecuteTime=now; 'y'T'2N3
executeUpdate(); =U=e?AOG2
} [0h* &
else{ vYYS.ve
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); dK[*
} _{[k[]
} MV%
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} M' a&
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 GU:r vS!
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类写好了,下面是在JSP中如下调用。 sM#!Xl;
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<% .WBI%ci
CountBean cb=new CountBean(); ;Fx')
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); _)OA$
CountCache.add(cb); eo>/
out.print(CountCache.list.size()+"<br>"); dCa}ITg
CountControl c=new CountControl(); [q|?f?Zl
c.run(); :D<:N*9i
out.print(CountCache.list.size()+"<br>"); Oqd"0Qt-
%>