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: JjD'2"z
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CountBean.java "`QI2{!l
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/* F@+FXnz
* CountData.java X4- _l$j
* nDt1oM
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* Created on 2007年1月1日, 下午4:44 @Ido6Z7
* PNjZbOmzS
* To change this template, choose Tools | Options and locate the template under
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* the Source Creation and Management node. Right-click the template and choose 9>@@W#TK~
* Open. You can then make changes to the template in the Source Editor. N-lo[bDJh
*/ qUZm6)p6[a
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package com.tot.count; qHAZ)Tz
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/** fV 6$YCf
* eU[f6OGqC
* @author X^2Txm d
*/ 3 &aBU[
public class CountBean {
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private String countType; F(yx/W>Br_
int countId; #_A <C+[
/** Creates a new instance of CountData */ U',.'"m
public CountBean() {} & o2F4
public void setCountType(String countTypes){ a!_vd B
this.countType=countTypes; W(C\lSE0
} %Ydzzr3
public void setCountId(int countIds){ x_C#ALq9
this.countId=countIds; #/UlW
} zF%'~S0{
public String getCountType(){ ,wI$O8"!j
return countType; Z#2AK63/T
} [(hB%x_"
public int getCountId(){ (c'=jJX
return countId; tt|v opz
} e)(m0m\
} shjq4#9
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CountCache.java @,Re<%\
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/* Up(Jw-.
* CountCache.java X5(S+;v"^
* s+=JT+g
* Created on 2007年1月1日, 下午5:01 \Y EV
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* Ab"mX0n
* To change this template, choose Tools | Options and locate the template under fP6]zy^*
* the Source Creation and Management node. Right-click the template and choose 4\#!Gv-
* Open. You can then make changes to the template in the Source Editor. 8-A *Jc
*/ CdTyUl
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package com.tot.count; R)%1GG4
import java.util.*; #rE#lHo
/** $'9b,- e
* nDdF(|Qt
* @author dHcGe{T^(
*/ NXwlRMbo
public class CountCache { ,P?R
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public static LinkedList list=new LinkedList(); {29x5J
/** Creates a new instance of CountCache */ jq4'=L$4
public CountCache() {} #4WA2EW
public static void add(CountBean cb){ p|W <xFk
if(cb!=null){ *kI1NchF
list.add(cb); F$Cf\#{3
} ' O\me
} DwQaj"1<%
} U 0$?:C+?
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CountControl.java .] S{T
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/* P5:X7[
* CountThread.java G4jaHpPi
* [@Db7]nG
* Created on 2007年1月1日, 下午4:57 E&?z-,-o@
* QU&b5!;&
* To change this template, choose Tools | Options and locate the template under l_GsQ0
* the Source Creation and Management node. Right-click the template and choose Lv;R8^n
* Open. You can then make changes to the template in the Source Editor. ty8\@l
*/ Vx]{<}(gr
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package com.tot.count; [WOLUb
import tot.db.DBUtils; !wws9
import java.sql.*; l!B)1
/** ] M"l-A
* ]}g;q*!J
* @author -3M6[`/
*/ hM!D6: t
public class CountControl{ x<
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private static long lastExecuteTime=0;//上次更新时间 ,j4 ;:F
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 );LkEXC_'
/** Creates a new instance of CountThread */ P'prp=JD
public CountControl() {} =H'7g6
public synchronized void executeUpdate(){ ^
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Connection conn=null; 49o5"M(
PreparedStatement ps=null; NqsIMCl
try{ `Gl@?9,i
conn = DBUtils.getConnection(); B}=
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conn.setAutoCommit(false); DU6AlNx
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); G]fl33_}l
for(int i=0;i<CountCache.list.size();i++){ $7{V+>
CountBean cb=(CountBean)CountCache.list.getFirst(); >$]SYF29
CountCache.list.removeFirst(); b {e nD
ps.setInt(1, cb.getCountId()); q9j9"M'
ps.executeUpdate();⑴ F=C8U$'S
//ps.addBatch();⑵ n<;TBK
} =N-,.{`
//int [] counts = ps.executeBatch();⑶ f
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conn.commit(); ~Tv
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}catch(Exception e){ 2nOoG/6
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e.printStackTrace(); PjEKZHHz
} finally{ ZbJUOa?WF
try{ y%CaaK=V3
if(ps!=null) { |q?I(b4 Q@
ps.clearParameters(); 'J^E|1P
ps.close(); jV^Dj
ps=null; ".z~c%'
} @b=b>V[d6
}catch(SQLException e){} ,4ftQJ
DBUtils.closeConnection(conn); Z']D8>d
} rJJI<{$
} p1p4t40<l
public long getLast(){ %J\1W"I?
return lastExecuteTime; J;Az0[qMR
} { U a19~'>
public void run(){ Qci<cVgP
long now = System.currentTimeMillis(); NfcQB;0
if ((now - lastExecuteTime) > executeSep) { |y@TI
//System.out.print("lastExecuteTime:"+lastExecuteTime); e.eQZ5n~q`
//System.out.print(" now:"+now+"\n"); {\G4YQ
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); zO`54^
lastExecuteTime=now; $l}MB7
executeUpdate(); H"8+[.xBh
} b'fj
else{ x,"'\=|s*
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ,R$n I*mf_
} 'j];tO6GfC
} j'i-XIs
}
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//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|}|V5
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类写好了,下面是在JSP中如下调用。 { hUbK+dKZ
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<% }' `2C$
CountBean cb=new CountBean(); ZWW:-3
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); a
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CountCache.add(cb); :NHh`@0F
out.print(CountCache.list.size()+"<br>"); LRD71*/
CountControl c=new CountControl(); NG@9}O
c.run(); <2w@5qL
out.print(CountCache.list.size()+"<br>"); SE{$a3`UzP
%>