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: :'\4%D=w
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CountBean.java 'Gn-8r+
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/* 4v@urW s
* CountData.java fxW,S
* 6]GEn=t
* Created on 2007年1月1日, 下午4:44 r6B\yH2
* F4!,8)}
* To change this template, choose Tools | Options and locate the template under ^uU'Qc4S=
* the Source Creation and Management node. Right-click the template and choose {l /]+8G^
* Open. You can then make changes to the template in the Source Editor. A5d(L4Q]a(
*/ [dszz7/L
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package com.tot.count; ;n-)4b]\
# g.J,L
/** P)7_RE*gY
* SUSam/xeg"
* @author <"SDU_<xG
*/ Je|D]w
public class CountBean { IEi E6z]L(
private String countType; |sM#nhxK
int countId; amPC C
/** Creates a new instance of CountData */ Hk65c0
public CountBean() {} 6 (:^>@
public void setCountType(String countTypes){ X>i`z
this.countType=countTypes; Ch`nDIne
} (<u3<40[YN
public void setCountId(int countIds){ vV2px
this.countId=countIds; aFI?^"L
} ,bv?c@
public String getCountType(){ nm[ yp3B
return countType; ;$ot,mH?T
}
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public int getCountId(){ ya+eGD@N':
return countId; \u|8MEB
} 9Y9pKTU
} #3:;&@#
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CountCache.java S-FoyID\H
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/* myp}DI(
* CountCache.java Y,v8eOo45S
* J6*Zy[)%&S
* Created on 2007年1月1日, 下午5:01 ?}QHEk:H
* }m?1IU%q
* To change this template, choose Tools | Options and locate the template under tDuQ+|~M
* the Source Creation and Management node. Right-click the template and choose P,S$qD*4
* Open. You can then make changes to the template in the Source Editor.
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*/ 3@k;"pFa<
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package com.tot.count; uUAib<wdPL
import java.util.*; ~=t,g S
/** 7\'ow|)}v
* IN? A`A
* @author 97H2hYw9l
*/ #
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public class CountCache { _IAvFJI
public static LinkedList list=new LinkedList(); S9sFC!s1g
/** Creates a new instance of CountCache */ R5QSf+/T4
public CountCache() {} l8n}&zX
public static void add(CountBean cb){ gnS0$kCJ:
if(cb!=null){ &} b'cO
list.add(cb); !_+LmBd
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} d2w;d&2S
} AJRfl% 3
} (-\,t
~jd:3ip+!
CountControl.java Qp{rAAC:
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/* oa:GGW4Q
* CountThread.java AT^?PD_
* &i`\`6 q
* Created on 2007年1月1日, 下午4:57 =2VM(GtK>
* Dk#$PjcRE
* To change this template, choose Tools | Options and locate the template under Jo1=C.V`Y
* the Source Creation and Management node. Right-click the template and choose o;o
ji
* Open. You can then make changes to the template in the Source Editor. cw3JSz9
*/ "FC;k
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package com.tot.count; q9-=>
import tot.db.DBUtils; )Cuc]>SC
import java.sql.*; xACAtJ'gc
/** ~+VIELU<%
* (rcH\
* @author &~
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*/ l?_Iu_Qp
public class CountControl{ saOXbt(&
private static long lastExecuteTime=0;//上次更新时间 ;0V{^
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 XVi?-/2
/** Creates a new instance of CountThread */ X*F#=.lh
public CountControl() {} W
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public synchronized void executeUpdate(){ I71kFtvcy*
Connection conn=null; ]A;zY%>
PreparedStatement ps=null; 4ze-N8<[
try{ =K#D^c~
conn = DBUtils.getConnection(); mA5x ke_)
conn.setAutoCommit(false); Q!Rknj 2
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); M%f96XUM
for(int i=0;i<CountCache.list.size();i++){ i(q%EMf
CountBean cb=(CountBean)CountCache.list.getFirst(); <C\snB
CountCache.list.removeFirst(); /H+j6*}r
ps.setInt(1, cb.getCountId()); a;AvY O
ps.executeUpdate();⑴ 62&E]>A(i
//ps.addBatch();⑵ 4/S% eZB
} ya]CxnKR3
//int [] counts = ps.executeBatch();⑶ }q-_|(b;
conn.commit();
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}catch(Exception e){ tP2hU[7Z
e.printStackTrace(); >Pv#)qtm
} finally{ ]|[,N>
try{ rlYAy5&
if(ps!=null) { Q4Mp[
ps.clearParameters(); T78`~-D4<
ps.close(); l]whL1N3
ps=null; kUAj Q>
} ]zHUF!a*
}catch(SQLException e){} p=6Q0r|'
DBUtils.closeConnection(conn); #SQao;>
} U7U-H\t7
} lmb5Z-xB
public long getLast(){ qp>O#tj[
return lastExecuteTime; |yiM7U,i
} 1R)4[oYN\<
public void run(){ j+Nun
long now = System.currentTimeMillis(); KFHn)+*"
if ((now - lastExecuteTime) > executeSep) { UJ1Ui'a(!!
//System.out.print("lastExecuteTime:"+lastExecuteTime); D0,U2d
//System.out.print(" now:"+now+"\n"); &eq>>
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); v\ggFrG]
lastExecuteTime=now; RKaCX:
executeUpdate(); '7Dg+a^x7
} P?*$Wf,~n
else{ ;X6FhQ;{*0
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); I,D24W4l
} -~eNC^t;W
} !+&"y K@J
} \{L!hAw
//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 >6 [{\uPK
Px&*&^Gf[b
类写好了,下面是在JSP中如下调用。 [Y.3miE
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<% w\KO1 Ob
CountBean cb=new CountBean(); yhQv $D,^f
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); b|t` )BF
CountCache.add(cb); fkWuSGi
out.print(CountCache.list.size()+"<br>"); 9mkt.>$
CountControl c=new CountControl(); po+>83/!oq
c.run(); ?!1K@/!
out.print(CountCache.list.size()+"<br>"); zC6,m6Dv
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