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: [0G>=h@u
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CountBean.java 2tqO%8`_
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/* =`]yq;(C7j
* CountData.java cAc i2e
* ~L'}!'
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* Created on 2007年1月1日, 下午4:44 v+*l|!v
* }`9}Q
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* To change this template, choose Tools | Options and locate the template under r8~U@$BBK
* the Source Creation and Management node. Right-click the template and choose 2O5yS
* Open. You can then make changes to the template in the Source Editor. Aq{m42EAj
*/ P!";$]+
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package com.tot.count; t%AW0#TZ
*7I=vro
/** Ucnit^,
* !Jj=H()}
* @author YtrMJ"
*/ VRoeq {
public class CountBean { G#! j`
private String countType; '4A8\&lQO
int countId; cZ7b$MZ%9
/** Creates a new instance of CountData */ EF{_-FXY
public CountBean() {} -3r&O:
public void setCountType(String countTypes){ !lF|90=
this.countType=countTypes; 6X:-Z3
} #|8!0]n'
public void setCountId(int countIds){ Sk$XC
this.countId=countIds; dR_hPBn/@
} w`VmN}pR
public String getCountType(){ y o[!q|z
return countType; |[TH
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} sh?Dxodp9
public int getCountId(){ N3H!ptn37
return countId; >}/"gx
} +*
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} Q_#X*I
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CountCache.java ? F fw'O
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/* 0r=Lilu{q
* CountCache.java s/Wg^(&M
* r/L3j0
* Created on 2007年1月1日, 下午5:01 DRVvW6s
* v4|kiy
* To change this template, choose Tools | Options and locate the template under bah5 f
* the Source Creation and Management node. Right-click the template and choose Pwz^{*u]
* Open. You can then make changes to the template in the Source Editor. VPg`vI$(X
*/ *(d^k;
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package com.tot.count; M)EUR0>8
import java.util.*; 9&'Mb[C`"
/** v(4C?vxhG
* ( L RX
* @author gpr];lgS
*/ Dl/UZ@8pl
public class CountCache { c e=6EYl
public static LinkedList list=new LinkedList(); N
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/** Creates a new instance of CountCache */ k=bv!T_o
public CountCache() {} n*iaNaU"'
public static void add(CountBean cb){ M7,|+W/RK
if(cb!=null){ +U%lWE%
list.add(cb); _zm<[0(
} =$Q3!bJ
} ,-DE;l^Q=
} JEBo!9
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CountControl.java ? *I9
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/* %v~j10e
* CountThread.java 7X}_yMxc
* (DKpJCx
* Created on 2007年1月1日, 下午4:57 J(/
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* oRWsi/Zf
* To change this template, choose Tools | Options and locate the template under :@b>,{*4zS
* the Source Creation and Management node. Right-click the template and choose a9jY^E'|n
* Open. You can then make changes to the template in the Source Editor. p7H*Ff`
*/ >Q5E0 !]
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package com.tot.count; 6o A0a\G'
import tot.db.DBUtils; 9R;s;2$.
import java.sql.*; zLXtj-
/** 7P|(j<JX6'
* S8,+6+_7
* @author `O}.
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*/ <6L$:vT_
public class CountControl{ N{p2@_fnB
private static long lastExecuteTime=0;//上次更新时间 <O\z`aA'q
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 FT(EH
/** Creates a new instance of CountThread */ [V jd)%
public CountControl() {} y'yaCf
public synchronized void executeUpdate(){ ha8do^x
Connection conn=null; -U/&3
PreparedStatement ps=null; J;T_9
try{ 6lWO8j^BN
conn = DBUtils.getConnection(); i,yK&*>JJ
conn.setAutoCommit(false); $V~%$
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); Fx3VQ'%J
for(int i=0;i<CountCache.list.size();i++){ s.GhquFCrU
CountBean cb=(CountBean)CountCache.list.getFirst(); '{oe}].,
CountCache.list.removeFirst(); 4qm5`o\hb
ps.setInt(1, cb.getCountId()); eEc;w#
ps.executeUpdate();⑴ 5&9(d_#H
//ps.addBatch();⑵ {8B\-LUR
} J$WIF&*0@
//int [] counts = ps.executeBatch();⑶ =$`DBLX
conn.commit(); b$Uwj<v
}catch(Exception e){ %W&=]&L
e.printStackTrace(); A&t'uY6
} finally{ swLgdk{8n
try{ [#R%jLEJ2
if(ps!=null) { :sPku<1is
ps.clearParameters(); 8v]{ 5
ps.close(); TyBNRnkt
ps=null; 2Vu|uZd
} W>DpDrO4ml
}catch(SQLException e){} +j@|D@z
DBUtils.closeConnection(conn); M2zfN ru
} dU&.gFw1
} >$Fc=~;Ba
public long getLast(){ mML^kgy\N
return lastExecuteTime; U<6k!Y9ny
} dl":?D4H
public void run(){ 'g=yJ
long now = System.currentTimeMillis(); RD_;us@&&*
if ((now - lastExecuteTime) > executeSep) { -dvDAs{X
//System.out.print("lastExecuteTime:"+lastExecuteTime); `jZX(H
//System.out.print(" now:"+now+"\n"); MZd\.]G@
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); UxS;m4
lastExecuteTime=now; o"]eAQ
executeUpdate(); $&e(V6A@
} D{l.WlA.
else{ h
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//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); &^uzg&,;
} U/iAP W4U
} 6=@n
b3D%
} Uv+pdRXn
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 %#]T.g
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类写好了,下面是在JSP中如下调用。 _$bx4a
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<% )>Lsj1qk
CountBean cb=new CountBean(); {!/y@/NK2
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); V.-?aXQ *
CountCache.add(cb); <m6Xh^Ko;
out.print(CountCache.list.size()+"<br>"); ~<Lf@yu-{
CountControl c=new CountControl(); ?\O+#U%W
c.run(); "FXS;Jf
out.print(CountCache.list.size()+"<br>"); Cir =(
%>