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: e1j3X\ \
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CountBean.java C.[abpc
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/* af<R.
* CountData.java M &g1'zv?/
* 3b2[i,m<L
* Created on 2007年1月1日, 下午4:44 lef,-{X-
* R6A{u(
* To change this template, choose Tools | Options and locate the template under =k\V~8XZ
* the Source Creation and Management node. Right-click the template and choose fGtUr_D
* Open. You can then make changes to the template in the Source Editor. ZYy?JDAO
*/ |aovZ/b4
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package com.tot.count; W5^m[,GU'
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/** MM*B.y~TxZ
* .A. VOf_
* @author "[rChso
*/ Hq*\,`b&
public class CountBean { uwcm%N;I"
private String countType; Gb\Nqx(
int countId; Is $I;`
/** Creates a new instance of CountData */ ^T#bla893
public CountBean() {} #ONad0T;
public void setCountType(String countTypes){ <n)J~B^
this.countType=countTypes; j[Y$)HF
} kIlc$:K^
public void setCountId(int countIds){ 1@)kNg)*$
this.countId=countIds; '
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} 6{ql.2
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public String getCountType(){ ]c.1&OB7o
return countType; 75+#)hNa!P
} KTm^0:V[Oy
public int getCountId(){ ]b"Oy}ARW
return countId; bZE;}d
} vjcG
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} Pde|$!Jo
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CountCache.java Be=J*D!E=>
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/* kf8-#Q/B
* CountCache.java
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* `m.).Hda
* Created on 2007年1月1日, 下午5:01 jo8hVWJ7V*
* '
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* To change this template, choose Tools | Options and locate the template under &o$z[b
* the Source Creation and Management node. Right-click the template and choose gkJL=,
* Open. You can then make changes to the template in the Source Editor. sO,%Ok1
*/ >VQP,J{
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package com.tot.count; p5C:MA~*
import java.util.*; \DG
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/** 6QwVgEnSf
* =ZE]jmD4P
* @author Df\~ ZWs!
*/ csceu+IA
public class CountCache { ;#F/2UgHB
public static LinkedList list=new LinkedList(); KxZO.>,
/** Creates a new instance of CountCache */ `K ,{Y_
public CountCache() {} L9| 55z
public static void add(CountBean cb){ Ho}"8YEXNV
if(cb!=null){ J4yL"iMt
list.add(cb); Ry@QJn I<
} 6`>WO_<z
} o7/S'Haxc]
} E<j}"W$a
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CountControl.java pSjJ u D
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/* tl 0_Sd
* CountThread.java WF)(Q~op0U
* =6XJr7Ay8u
* Created on 2007年1月1日, 下午4:57 yqaLqZ$
* L\cd=&b`
* To change this template, choose Tools | Options and locate the template under JnWG_|m)
* the Source Creation and Management node. Right-click the template and choose 1S&GhJ<wJ
* Open. You can then make changes to the template in the Source Editor. 'MM%Sm,
*/ 81gcM?
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package com.tot.count; q#{.8H-X'
import tot.db.DBUtils; vD=>AAvG
import java.sql.*; Tz\ PQ)!
/** 64)Fz}
* ?ztI8I/
* @author BB x359
*/ /s@t-gTi
public class CountControl{ -C]k YQ
private static long lastExecuteTime=0;//上次更新时间 HHT_ }_?
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 9j0Hvo% T
/** Creates a new instance of CountThread */ !cLdoX
public CountControl() {} n~1F[ *
public synchronized void executeUpdate(){ RcZg/{[{
Connection conn=null; e-!6m#0
PreparedStatement ps=null; scf.>K2
try{ (E{>L).~
conn = DBUtils.getConnection(); WH>= *\
conn.setAutoCommit(false); <G};`}$a
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); o!]muO*Rm
for(int i=0;i<CountCache.list.size();i++){ QKW\z aG
CountBean cb=(CountBean)CountCache.list.getFirst(); 5r&bk`
CountCache.list.removeFirst(); }Y}f73-|
ps.setInt(1, cb.getCountId()); }McqoZ%F
ps.executeUpdate();⑴ :3J0Q
//ps.addBatch();⑵ ~XzT~WxW
} ;PS V3Zh
//int [] counts = ps.executeBatch();⑶ v qt#JdPp9
conn.commit(); 'n:|D7t
}catch(Exception e){ Vu0d\l^$
e.printStackTrace(); zBQV2.@
} finally{ wMW."gM|
try{ RP@U0o
if(ps!=null) { /C[Q?
ps.clearParameters(); q,i&%
ps.close(); *^ZJ&.
ps=null; J!{t/_aw
} "QKCZ8_C
}catch(SQLException e){} og`rsl
DBUtils.closeConnection(conn); i/vo
} 2
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} AiP#wK;
public long getLast(){ ]u]BxMs
return lastExecuteTime; Y3_C':r
} %Z8'h\|
public void run(){ w#XD4kwQG
long now = System.currentTimeMillis(); y*G3dWb
if ((now - lastExecuteTime) > executeSep) { wtl3Ex,DO
//System.out.print("lastExecuteTime:"+lastExecuteTime); =JkPE2mU
//System.out.print(" now:"+now+"\n"); diz=|g=w
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); Wbq0K6X
lastExecuteTime=now; 5*O*p `Ba
executeUpdate(); NmuzAZr
} NJNS8\4
else{ _%@dlT?
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); AV>_bw.
} |p .o ^
} [!~=m
} !*?|*\B^I
//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 ]c9\[Kdq}H
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类写好了,下面是在JSP中如下调用。 YE*%Y["
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<% AMw#_8Y
CountBean cb=new CountBean(); K7 J RCLA
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); "1l$]=C*
CountCache.add(cb); e9=UTn{!
out.print(CountCache.list.size()+"<br>"); vg-Ah6BC{
CountControl c=new CountControl(); #n7F7X
c.run(); zA>LrtyK(=
out.print(CountCache.list.size()+"<br>"); 2zV{I*
%>