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: du_4eB
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CountBean.java rzUlO5?R=
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/* Rko M~`CT
* CountData.java XKS8K4"
* i{Ds&{
* Created on 2007年1月1日, 下午4:44 <CZgQ\Mt
* |gx~gG<
* To change this template, choose Tools | Options and locate the template under u5+|Su
* the Source Creation and Management node. Right-click the template and choose *2e!M^K<
* Open. You can then make changes to the template in the Source Editor. }r%X`i|
*/ O"Q7Rx
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package com.tot.count; <%P2qgz5
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/** xr%#dVk
* Ln!A:dP}c-
* @author [9o4hw
*/ kXrlSaIc
public class CountBean { KOhA)
private String countType; ^5; `-Ky
int countId; />44]A<
/** Creates a new instance of CountData */ _zMgoc7
public CountBean() {} =Vw
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public void setCountType(String countTypes){ 69G`2_eKCp
this.countType=countTypes; Ba'LRz
} Bd~1P/
public void setCountId(int countIds){ T.mmmT
this.countId=countIds; k[kju%i4
} ._PzYE|m2
public String getCountType(){ ~}"]&%Q{J
return countType; ?LK 2g
} !EIjN
public int getCountId(){ 1P(&J
return countId; U;q];e:,=}
} ~xLJe`"JUx
} %$5H!!~o
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CountCache.java N?P%-/7
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/* eq4C+&O&
* CountCache.java Wwujh2g"0|
* >znRyQ~bM
* Created on 2007年1月1日, 下午5:01 -E4XIn
* Sa1l=^
* To change this template, choose Tools | Options and locate the template under iyta;dw9
* the Source Creation and Management node. Right-click the template and choose >>{FzR
* Open. You can then make changes to the template in the Source Editor. %9oYw9H!
*/ O1'm@
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package com.tot.count; "Wo,'8{v
import java.util.*; JW.=T)
/** 9f+>ix,ek*
* C3NdE_E
* @author \ZU1Jb1c
*/ umi5Wb<
public class CountCache { s?R2B)a
public static LinkedList list=new LinkedList(); h vka{LD
/** Creates a new instance of CountCache */ cWyW~Ek
public CountCache() {} `n5"0QRd
public static void add(CountBean cb){ @&|l^ 1
if(cb!=null){ *+)AqKP\Kv
list.add(cb); XolZonJr
} f"1>bW>R+
} *3/T;x.
} ]n."<qxeT
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CountControl.java :>Rv!x`
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/* -#!x|ne
* CountThread.java /,=@8k!t?
* { FZ=olZ
* Created on 2007年1月1日, 下午4:57 3psU?8(
* Z_1U9+,
* To change this template, choose Tools | Options and locate the template under 3"n\8#X{
* the Source Creation and Management node. Right-click the template and choose ,L bBpi=TJ
* Open. You can then make changes to the template in the Source Editor. +l3=3
*/ 0sca4G0{
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package com.tot.count; +5VLw
import tot.db.DBUtils; QTX8
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import java.sql.*; w@JKl5
/** U8qtwA9t
* LI2&&Mw
* @author JM1R ;i6
*/ D%6;^^WyUx
public class CountControl{ GaX[C<Wt
private static long lastExecuteTime=0;//上次更新时间 g<{xC_J
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 )q7UxzE+
/** Creates a new instance of CountThread */ m<FOu<y
public CountControl() {} 8#!i[UFdj
public synchronized void executeUpdate(){ 5%sE]Y#
Connection conn=null; 2MZCw^s>
PreparedStatement ps=null; Vq;dJ%sY
try{ w2_bd7Wp<
conn = DBUtils.getConnection(); ~.;<
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conn.setAutoCommit(false); ;JZS^Wa
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); yE[#ze
for(int i=0;i<CountCache.list.size();i++){ r'QnX;99T
CountBean cb=(CountBean)CountCache.list.getFirst(); 7$h#OV*@,
CountCache.list.removeFirst(); V,rq0xW
ps.setInt(1, cb.getCountId()); 3gd&i
ps.executeUpdate();⑴ oy<WsbnS
//ps.addBatch();⑵ 8JmFi
} rV08ad
//int [] counts = ps.executeBatch();⑶ M%jPH
conn.commit(); Y"A/^]
}catch(Exception e){ UfS%71l.$
e.printStackTrace(); .9Y)AtJTS
} finally{ ~3uP6\F
try{ V< k8N^
if(ps!=null) { C8z{XSo
ps.clearParameters(); da)NK!
ps.close(); -B86U6^s
ps=null; M1KqY: 9E
} -D6exTxh"
}catch(SQLException e){} vWGwVH/K
DBUtils.closeConnection(conn); r@ZJ{4\Q
} u\eEh*<7q
} e=O,B8)_
public long getLast(){ */|BpakD<
return lastExecuteTime; yj^+G
} $56,$K`H
public void run(){ xyI}y(CN1
long now = System.currentTimeMillis(); /7gOSwY
if ((now - lastExecuteTime) > executeSep) { q$=#A7H>3)
//System.out.print("lastExecuteTime:"+lastExecuteTime); (<^ yqH?
//System.out.print(" now:"+now+"\n"); 6{txm+U
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); itC-4^
lastExecuteTime=now; Ja9e^`i;
executeUpdate(); D9M:^
} s6>ZREf#J
else{ =:~R=/ZXk
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); KEWTBBg
} >,td(= :
} hdrm!aBd
} hP15qKy
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 W*2U="t
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类写好了,下面是在JSP中如下调用。 }sxYxn~
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<% Dc,I7F|%
CountBean cb=new CountBean(); ~ 0M'7q'
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); P-9<YN
CountCache.add(cb); %$b:X5$Z
out.print(CountCache.list.size()+"<br>"); z*-2.}&U<
CountControl c=new CountControl(); A{A\RSZ0
c.run(); ?!+MM&c-n
out.print(CountCache.list.size()+"<br>"); P'_H/r/#
%>