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: fSL'+l3
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CountBean.java ?~_[/
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/* = "N?v-
* CountData.java 61"w>;d6
* #;WKuRv
* Created on 2007年1月1日, 下午4:44 U<"@@``+N
* +LEU|#
* To change this template, choose Tools | Options and locate the template under @|hn@!YK
* the Source Creation and Management node. Right-click the template and choose .dvO Ut I[
* Open. You can then make changes to the template in the Source Editor. E2Jmo5yJR
*/ S~+er{,ht4
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package com.tot.count; TTSyDl
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/** $QB~ x{v@n
*
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* @author ]3/_?n-"`
*/ {0t-Q k
public class CountBean { d2!A32m
private String countType; B{^ojV;]m
int countId; G7yR&x^
/** Creates a new instance of CountData */ m[t4XK
public CountBean() {} btV
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public void setCountType(String countTypes){ nR2pqaKc
this.countType=countTypes; lz-t+LD@ST
} &0='z
public void setCountId(int countIds){ ~s[St0
this.countId=countIds; "Om4P|
} pm 4"Q!K
public String getCountType(){ c%bGVRhE
return countType; -? |-ux
} U/|;u;H=
public int getCountId(){ %JsCw8C6?
return countId; 4EZl
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} ^G~C#t^
} A/%+AH(
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CountCache.java q#n0!5Lv2
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/* M'"@l$[QM
* CountCache.java JO^E x1c
* S.#IC
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* Created on 2007年1月1日, 下午5:01 k m(Mv
* ZI0C%c.~
* To change this template, choose Tools | Options and locate the template under t;?TXAA
* the Source Creation and Management node. Right-click the template and choose f L}3I(VK
* Open. You can then make changes to the template in the Source Editor. 42Vz6 k:
*/ <.HDv:
{#]vvO2~$
package com.tot.count; ,8vqzI
import java.util.*; pFZ2(b&
/** H1bPNt63
* @0mR_\u\
* @author =%\y E0#
*/ !4blX'<w
public class CountCache { :4(.S<fH)-
public static LinkedList list=new LinkedList(); uoIvFcb^
/** Creates a new instance of CountCache */ D_W,Jmet
public CountCache() {} TO|&}sDh
public static void add(CountBean cb){ LG/6_t}
if(cb!=null){ GF3"$?Cw
list.add(cb); vp>,}nx4
} g3`:d)|
} 4.^1D';(
} jQgy=;?Lwm
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CountControl.java :k"VR,riF
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/* =WYI|3~Cz
* CountThread.java *u|bmt
* c~0hu*&
* Created on 2007年1月1日, 下午4:57 r/32pY
* # RG/B2
* To change this template, choose Tools | Options and locate the template under Rpi@^~aPE
* the Source Creation and Management node. Right-click the template and choose *_aeK~du.
* Open. You can then make changes to the template in the Source Editor. <Kq4thR
*/ O$2'$44HX
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package com.tot.count; \"X<\3z2
import tot.db.DBUtils; }!W,/=z*
import java.sql.*; F_?aoP&5
/** @
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* 20O\@}2q2M
* @author n'&Cr0{
*/ ~`<(T)rs
public class CountControl{ 6;:s N8M+1
private static long lastExecuteTime=0;//上次更新时间 C_RxJWka
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 **%/Ke[
/** Creates a new instance of CountThread */ %DKQ
public CountControl() {} 5c W2
public synchronized void executeUpdate(){ )Ycjx~
Connection conn=null; Wd R ~
PreparedStatement ps=null; Q|O! cEW/
try{ qNH=
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conn = DBUtils.getConnection(); 9qHbV
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conn.setAutoCommit(false); C|@6rr9TA
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); "8'aZ.P
for(int i=0;i<CountCache.list.size();i++){ %s^2m"ca}=
CountBean cb=(CountBean)CountCache.list.getFirst(); ~Lyy7B9
CountCache.list.removeFirst(); {NS6y \,
ps.setInt(1, cb.getCountId()); R43yr+p
ps.executeUpdate();⑴ 5$(qnOi
//ps.addBatch();⑵ ncGg@$E
} L*rND15
//int [] counts = ps.executeBatch();⑶ *gJ:irah
conn.commit(); #-0}r
}catch(Exception e){ 0&YW#L|J
e.printStackTrace(); ^Ia:e
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} finally{ ~BSIp
.
try{ u Z(vf
if(ps!=null) { r fl-(_3
ps.clearParameters(); @-7h}2P Q
ps.close(); f:=y)+@1My
ps=null; 6eUM[C.
} {GTOHJ2
}catch(SQLException e){} E>bK-jG
DBUtils.closeConnection(conn); bpQ5B'9
} #`1@4,iC
} sbxOnwP\
public long getLast(){ W!R}eLf@
return lastExecuteTime; ,<pk&54.@'
} ]
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public void run(){ ~w&_l57
long now = System.currentTimeMillis(); D9cpw0{nc
if ((now - lastExecuteTime) > executeSep) { .+;;-]})
//System.out.print("lastExecuteTime:"+lastExecuteTime); .%.bIT
//System.out.print(" now:"+now+"\n"); V*uoGWL]+
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); l;N?*2zm[
lastExecuteTime=now; ?gp:uxq,.
executeUpdate(); N,iYUM?
} cVx#dDdA
else{ pCE,l'Xa
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); :{(` ;fJ
} +zU[rhMk'
} 0gI^GJN%Y!
} (iwZs:k-
//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 baD`k?](
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类写好了,下面是在JSP中如下调用。 7)2Co[t
tSP)'N<
<% n#{z"G
CountBean cb=new CountBean(); Qx
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{
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); |wnXBKV(
CountCache.add(cb); f.Uvf^T}2
out.print(CountCache.list.size()+"<br>"); mHm"QBa!
CountControl c=new CountControl(); q0Hor
c.run(); O?6ph4'
out.print(CountCache.list.size()+"<br>"); 8"f Z>XQ
%>