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: xH0Bk<`V:
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CountBean.java A%Ao yy4E
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/* I6UZ_H'E
* CountData.java e3[N#ryt
* 'tOo0Zgc
* Created on 2007年1月1日, 下午4:44 9yQ[ *
* b"J(u|Du`
* To change this template, choose Tools | Options and locate the template under FQ[::*-
* the Source Creation and Management node. Right-click the template and choose Z0x N9S
* Open. You can then make changes to the template in the Source Editor. :f`1
*/ *l|CrUa
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package com.tot.count; g{&ux k);
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/** ,5nrovv
* \aG>(Mr
* @author 1=s%.0
*/ ]+oPwp;il
public class CountBean { p%n}a%%I
private String countType; YoXXelO&
int countId; 0 {w?u %'
/** Creates a new instance of CountData */ t4nAy)I)P
public CountBean() {} %_5B"on
public void setCountType(String countTypes){ %H:!/'45
this.countType=countTypes; ' e-FJ')|
} J^u8d?>r
public void setCountId(int countIds){ [
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this.countId=countIds; b-wFnMXk+
} D:%v((Ccw
public String getCountType(){ (fq>P1-
return countType; zd+8fP/UB
} W8\K_M}
public int getCountId(){ "8s0~[6S
return countId; *.20YruU;j
} -O{Af
} =3sBWDB[
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CountCache.java #Ez>]`]TB
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/* ,!c.
* CountCache.java 8K{
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* 5pz%DhjLo
* Created on 2007年1月1日, 下午5:01 4e9mN~
* @HR]b^2E
* To change this template, choose Tools | Options and locate the template under \4mw>8wA
* the Source Creation and Management node. Right-click the template and choose sz_|py?0
* Open. You can then make changes to the template in the Source Editor. `_<K#AG Ai
*/ V\Rbnvq
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package com.tot.count; T-eeYw?Yf
import java.util.*; Cdc6<8
/** 1}9@aKM
* dqnxhN+&
* @author S=2-<R
*/ fk9FR^u
public class CountCache { 9"oc.ue.2D
public static LinkedList list=new LinkedList(); >lRX+?
/** Creates a new instance of CountCache */ Q4C28-#
public CountCache() {} )
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public static void add(CountBean cb){ {3'z}q
if(cb!=null){ _"=Y j3?G%
list.add(cb); x?T/=C
} 1)vdM(y3j
} wS#.Wzp.w
} *s<FE F
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CountControl.java 2?#IwT'
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/* }h>QkV,{2
* CountThread.java pGh2 4E
* /wVrr%SN
* Created on 2007年1月1日, 下午4:57 ?$v#;n?@I
* h`,dg%J*B
* To change this template, choose Tools | Options and locate the template under [<7Hy,xr_
* the Source Creation and Management node. Right-click the template and choose 8v_HIx0xu
* Open. You can then make changes to the template in the Source Editor. \_qiUvPf\
*/ tGe|@.!
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package com.tot.count; 94LFElE3
import tot.db.DBUtils; '*|Wi}0R
import java.sql.*; 4l560Fb'U
/** L@XhgQ
* b&. o9PV"
* @author /X{:~*.z
*/ 6MqJy6
public class CountControl{ \|R P-8
private static long lastExecuteTime=0;//上次更新时间 J[du>1D
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 s9?klJg
/** Creates a new instance of CountThread */ a=T_I1
public CountControl() {} aovRm|aOo'
public synchronized void executeUpdate(){ }>>lgW>n,;
Connection conn=null; P'xq+Q
PreparedStatement ps=null; ojni+} >_
try{ 9;NR
conn = DBUtils.getConnection(); *^ g7kCe(
conn.setAutoCommit(false); T]Pp\6ff
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ORD@+ {
for(int i=0;i<CountCache.list.size();i++){ " P c"{w
CountBean cb=(CountBean)CountCache.list.getFirst(); MPhO#;v
CountCache.list.removeFirst(); !O~EIz
ps.setInt(1, cb.getCountId()); y4^6I$M7V
ps.executeUpdate();⑴ !inonR
//ps.addBatch();⑵ :Em[>XA
} [R TB|0Q
//int [] counts = ps.executeBatch();⑶ AtGk
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conn.commit(); JL=MlZ
}catch(Exception e){ k.NgE/;3
e.printStackTrace(); |9$K'+'
} finally{ t
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try{ wK!4:]rhG
if(ps!=null) { 18jI6$DY
ps.clearParameters(); 7;ZSeQyC
ps.close(); +pURF&Pr
ps=null; 3@f@4t@5V
} #XE`8$
}catch(SQLException e){} +q[puFfl
DBUtils.closeConnection(conn); ;9MsV.n
} OQIQ
} bsO78a~=P
public long getLast(){ Ii_X^)IL(
return lastExecuteTime; =yJJq=!
} TL lR"L5
public void run(){ #8H
long now = System.currentTimeMillis(); Ze[ezu
if ((now - lastExecuteTime) > executeSep) { (sSMH6iCif
//System.out.print("lastExecuteTime:"+lastExecuteTime); GSj04-T"
//System.out.print(" now:"+now+"\n"); sN.h>bd
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 4IuQQ
lastExecuteTime=now; C(qqGK{
executeUpdate(); uU=O 0?'zq
} a*@ 6G
else{ f^z/s6I0
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); S4508l
} YtI2Vr/9
} _1S^A0ft
} `uo'w:Q
//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'T/I\tB
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类写好了,下面是在JSP中如下调用。 Rrmk\7/
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<% %Aq+t&-BCX
CountBean cb=new CountBean(); {PZNJ 2~
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); {L^b['h@
CountCache.add(cb); fS+Ga1CsH
out.print(CountCache.list.size()+"<br>"); bR"hl? &c
CountControl c=new CountControl(); p}_n
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c.run(); U2l7@uDr;
out.print(CountCache.list.size()+"<br>"); "$#X[.
%>