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: "u.4@^+i
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CountBean.java w/Ej>OS
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/* O({vHqN>
* CountData.java HS[N]'dc
* t]PO4GA
* Created on 2007年1月1日, 下午4:44 UCDvN
* u[yUUYe
* To change this template, choose Tools | Options and locate the template under ZW>?y$C+
* the Source Creation and Management node. Right-click the template and choose
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* Open. You can then make changes to the template in the Source Editor. GFmVR2z_+
*/ i=DoK{`L
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package com.tot.count; Ey* *j
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/** `z]MQdE_w
* 50J"cGs~
* @author Q?"-[6[v
*/ XF=GmkO
public class CountBean { 53jtwklA
private String countType; o;<oXv
int countId; MF%>avRj
/** Creates a new instance of CountData */ a eo/4
public CountBean() {} BR[f{)a5
public void setCountType(String countTypes){ b*@y/ e\u`
this.countType=countTypes;
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} A"`(^#a
public void setCountId(int countIds){ .f~x*@
this.countId=countIds; q9mYhT/Im
} FMBzTD
public String getCountType(){ ~IP3~m D
return countType; ]'a9>o
} 1XvB,DhJ
public int getCountId(){ ]&kzIxh
return countId; jf'#2-
} BoMf#l.3B
} KXy|Si8w
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CountCache.java
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/* $xU5vCwAo
* CountCache.java KN"V(<!)~
* #7~i.8L
* Created on 2007年1月1日, 下午5:01 |[]"{Eo"}
* 2n`OcXCh/
* To change this template, choose Tools | Options and locate the template under 'G-zJcU
* the Source Creation and Management node. Right-click the template and choose *=O~TY<](
* Open. You can then make changes to the template in the Source Editor. /92m5p
*/ |K%nVcR=
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package com.tot.count; h
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import java.util.*; V/jEMJNks
/** Q<F-l.q
* _a3,Zuv
* @author SKf[&eP,G
*/ _Xn[G>1
public class CountCache { d;kdw
public static LinkedList list=new LinkedList(); Y)=89s&t
/** Creates a new instance of CountCache */ E'J| p7
public CountCache() {} 8}0O @ wq
public static void add(CountBean cb){ jLEwFPz
if(cb!=null){ Zg@NMT
list.add(cb); utz!ElzA
} TLk=HGw
} oU.LYz_
} 1Lf:TQB
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CountControl.java k^IC"pUc
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/* .CL\``
* CountThread.java 6jRUkI-!
* 1x^(vn#=
* Created on 2007年1月1日, 下午4:57 |<n+6
* k8;
* To change this template, choose Tools | Options and locate the template under D%0GXUp
* the Source Creation and Management node. Right-click the template and choose W&U
Nk,
* Open. You can then make changes to the template in the Source Editor. =N9a!ii|
*/ K]
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package com.tot.count; x@I(G "
import tot.db.DBUtils; 6BJPQdqSl
import java.sql.*; _"PTO&E
/** }cL9`a9j
* YAIDSZ&l[
* @author U[a;eOLx
*/ Ba\l`$%X
public class CountControl{ T`;>Kq:s
private static long lastExecuteTime=0;//上次更新时间 s9wcZO
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 @Ee'nP
/** Creates a new instance of CountThread */ tfr*/+F
public CountControl() {} wv2
public synchronized void executeUpdate(){ >HUU`= SC
Connection conn=null; J/j?;qx]j
PreparedStatement ps=null; Xw=>L#Q
try{ R18jju>Zr
conn = DBUtils.getConnection(); ov=[g l
conn.setAutoCommit(false); Fvy__qcHi
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); n0T\dc~
for(int i=0;i<CountCache.list.size();i++){ aIv>X@U}
CountBean cb=(CountBean)CountCache.list.getFirst(); @}K'Ic
CountCache.list.removeFirst(); McgTTM;E
ps.setInt(1, cb.getCountId()); %r0yBK2uOp
ps.executeUpdate();⑴ 3+<}Hm+
//ps.addBatch();⑵ !po8[fz~x
} <|M cE
//int [] counts = ps.executeBatch();⑶ ()Z! u%j
conn.commit();
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}catch(Exception e){ cp0@wC#d
e.printStackTrace(); $T\z
} finally{ c]>s(/}T
try{ :t6w+h
if(ps!=null) { d7y`AS@q6
ps.clearParameters(); Zu\(XN?62
ps.close(); ;[]{O5TB
ps=null; :!M/9D*}0
} #ra~Yb-F
}catch(SQLException e){} V fJYYR
DBUtils.closeConnection(conn); vs/.'yD/C
} )v-sde\
} +-=w`
public long getLast(){ +zQ
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return lastExecuteTime; 1 f ]04TI
} x1\,WOrmK
public void run(){ $!L'ZO1_r
long now = System.currentTimeMillis(); M1^?_;B
if ((now - lastExecuteTime) > executeSep) { 92F(Sl
//System.out.print("lastExecuteTime:"+lastExecuteTime); WHQg6r
//System.out.print(" now:"+now+"\n"); + RX{
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 8F(lW)A n
lastExecuteTime=now; ,BCtNt(
executeUpdate(); F$UvYy4O d
}
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else{ #Mt'y8|}$
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); V]cD^Fqp
} bwG2=
} ^[noGjy
} 1D03Nbh|5
//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-\
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类写好了,下面是在JSP中如下调用。 .eAN`-t;
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<% G[1:<Vg8
CountBean cb=new CountBean(); sr+*
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); Q#
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CountCache.add(cb); \WG6\Zg0A
out.print(CountCache.list.size()+"<br>"); |*5K fxq
CountControl c=new CountControl(); ?(el6 J}
c.run(); %|$h<~
out.print(CountCache.list.size()+"<br>"); ^uIP
%>