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: vf+z0df
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CountBean.java m6$&yKQ-=h
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/* nLG)>L
* CountData.java T6=|)UTe1
* 5y\35kT'
* Created on 2007年1月1日, 下午4:44 7Hgn/b[?b
* rwP)TJh"
* To change this template, choose Tools | Options and locate the template under 6-TYOUm
* the Source Creation and Management node. Right-click the template and choose 1IS1P)4_0
* Open. You can then make changes to the template in the Source Editor. ?b{y#du2a
*/ f5b|,JJ
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package com.tot.count; &0%Zb~ts
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/** j%-Ems*H
* \ERxr
* @author F8{gJaP x
*/ ]sL.+.P
public class CountBean { Q#Zazvk
private String countType; a=A12<
int countId; rr1'|
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/** Creates a new instance of CountData */ UXdc'i g
public CountBean() {} Qj_)^3`e
public void setCountType(String countTypes){ zuW4gJ
this.countType=countTypes; HR8YPU5
} X';qcn_^
public void setCountId(int countIds){ V6HZvuXV!
this.countId=countIds; ,Ww}xmq1H
} "5
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public String getCountType(){ sCzpNJ"8
return countType; Zy;jp*Q
} HJ]e%og
public int getCountId(){ 1Td`S1'#yg
return countId; +ZW>JjP*
} iQ8{N:58DN
} d v[.u{#tP
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CountCache.java r,0D I
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/* vfv?QjR
* CountCache.java L
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* +pYwc0~
* Created on 2007年1月1日, 下午5:01 0=6mb]VUi=
* 1t &_]q_
* To change this template, choose Tools | Options and locate the template under "U4c'iW
* the Source Creation and Management node. Right-click the template and choose YjTr49Af0
* Open. You can then make changes to the template in the Source Editor. U,v`md@PX
*/ |UWIV
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package com.tot.count; ]1d)jWG
import java.util.*; _BJ:GDz>
/** A>upT'
* d$bO.t5CLh
* @author P![ZO6`:W'
*/ gL&w:_
public class CountCache { Tc||96%2^
public static LinkedList list=new LinkedList(); vnQFq
/** Creates a new instance of CountCache */ .[]S!@+%
public CountCache() {} P[q>;Fx*
public static void add(CountBean cb){ ArAe=m!u
if(cb!=null){ JvW7h(u7g
list.add(cb); ~(XaXu
} ov,
} V'W*'wo
} E=,5%>C0#%
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CountControl.java 6:B,ir
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/* {Hl(t$3V`
* CountThread.java }(Fmr7%m
* =CD6x=
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* Created on 2007年1月1日, 下午4:57 U+B"$yBR
* *k,3@_5
* To change this template, choose Tools | Options and locate the template under yLfyLyO L
* the Source Creation and Management node. Right-click the template and choose E Zf|>^N
* Open. You can then make changes to the template in the Source Editor. 9D=X3{be#
*/ /ZabY
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package com.tot.count; G`0{31us
import tot.db.DBUtils; rCA!b"C2
import java.sql.*; UsU
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/** RxJbQs$Ph
* [9Rh" H;h
* @author UMd.=HC L
*/ hN=kU9@knC
public class CountControl{ NdLe|L?c
private static long lastExecuteTime=0;//上次更新时间 k`N*_/(|n
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ">1wPq&
/** Creates a new instance of CountThread */ M*3G
public CountControl() {} [j@i^B &
public synchronized void executeUpdate(){ zzI,iEG
Connection conn=null; 9ETdO,L)f
PreparedStatement ps=null; x+6z9{O
try{ 'h6G"=+
conn = DBUtils.getConnection(); O^-QqCZE
conn.setAutoCommit(false); gTTKjlI[
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); :'ZR!w
for(int i=0;i<CountCache.list.size();i++){ 3-:^mRPJ
CountBean cb=(CountBean)CountCache.list.getFirst(); R+uZi~
CountCache.list.removeFirst(); 3T]cDVQ_
ps.setInt(1, cb.getCountId()); We}9'X}
ps.executeUpdate();⑴ 44P [P{y
//ps.addBatch();⑵ n5A|Zjk;
} M=;csazN
//int [] counts = ps.executeBatch();⑶ {%>~
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conn.commit(); gE@Pb
}catch(Exception e){ Y]`=cR`/"
e.printStackTrace(); XZ@+aG_%q
} finally{ (9aOET>GG
try{ 3Q62H+MC
if(ps!=null) { s-WZ3g
ps.clearParameters(); jJ<&!=
ps.close(); LA\3 ,Uv
ps=null; V(ww
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} l6WEx
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}catch(SQLException e){} DIQ30(MS
DBUtils.closeConnection(conn); DU"Gz!X]Jd
} 2RNee@!JJP
} p2b~k[
public long getLast(){ <#M1I!R
return lastExecuteTime; 5TuwXz1v
} e#mf{1&
public void run(){ ^znUf4N1
long now = System.currentTimeMillis(); jmq^98jB
if ((now - lastExecuteTime) > executeSep) { lc5(^~
//System.out.print("lastExecuteTime:"+lastExecuteTime); $X)|`$#pL#
//System.out.print(" now:"+now+"\n"); b1IAp >*2l
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ]JGq{I>%+6
lastExecuteTime=now; jsgDJ}
executeUpdate(); ~s'}_5;VY
} aDX&j2/
else{ cyWb*Wv
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ~x'8T!M{
} Hc\@{17
} =2GKv7q$x,
} [Fag\/Y+
//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 cOpe6H6,bz
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类写好了,下面是在JSP中如下调用。 wVf 7<@/y
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<% |-/@3gPO
CountBean cb=new CountBean(); L6nsVL&
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); )^qXjF
CountCache.add(cb); Z D"*fr
out.print(CountCache.list.size()+"<br>"); o ?05bv
CountControl c=new CountControl(); cL4Go,)w
c.run(); S m=ln)G=
out.print(CountCache.list.size()+"<br>"); \^y~w~g?
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