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: (0kK_k'T
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CountBean.java 2SR: FUV/
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/* Hl
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* CountData.java 3%=~)7cF
* G'aDb/
* Created on 2007年1月1日, 下午4:44 tcog'nAz
* y Fq&8 x<X
* To change this template, choose Tools | Options and locate the template under =[jXe
* the Source Creation and Management node. Right-click the template and choose hqkz^!rp
* Open. You can then make changes to the template in the Source Editor. URbletSBQ
*/ ?p8_AL'RS
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package com.tot.count; ?=fyc1
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/** _ZkI)o
* GF=g<H
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* @author /fV;^=:8c
*/ jsi!fx2Rm
public class CountBean { "|KP'<8%
private String countType; w_u\sSQ`!
int countId; qK&d]6H
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/** Creates a new instance of CountData */ 3>VL}Ui}
public CountBean() {} CF5`-wj/#
public void setCountType(String countTypes){ 0>Z_*U~6
this.countType=countTypes; *%@h(js
} =+d?x56
public void setCountId(int countIds){ Vj>8a)"B5a
this.countId=countIds; sZF6h=67D
} <0q;NrvUb
public String getCountType(){ v0jgki4t
return countType; ]
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} /%A*aGyIc
public int getCountId(){ I`4*+a'q&
return countId; L4y4RG/SJ:
} Nf1-!u7
} k7usMVAA
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CountCache.java SS.dY""89
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/* 0b(N^$js'
* CountCache.java K:30_l<
* e'D&8z_;
* Created on 2007年1月1日, 下午5:01 I"7u2"@-8j
* bhlG,NTP
* To change this template, choose Tools | Options and locate the template under l"]}Ts#
* the Source Creation and Management node. Right-click the template and choose GYUn6P
* Open. You can then make changes to the template in the Source Editor. p,i[W.dy.'
*/ jPW#(3hoE
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package com.tot.count; "o}+Ciul
import java.util.*; ,]c
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/** 3
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* pr UM-u8
* @author M?uC%x+S$_
*/ AX/m25x
public class CountCache { w!clI8v/
public static LinkedList list=new LinkedList(); ZSd4z:/
/** Creates a new instance of CountCache */ Pce;r*9
public CountCache() {} i9][N5\$
public static void add(CountBean cb){ JbQ) sp
if(cb!=null){ 6 3,H{
list.add(cb); I,@6J(9
} <1\Nb{5
} *N'p~LJ
} "d5n \@[t
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CountControl.java ?zHPJLv|Y
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/* MfQ?W`Kop
* CountThread.java )iK6:s#
* k-OPU,
* Created on 2007年1月1日, 下午4:57 Lrq.Ab#
* m#Z#
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* To change this template, choose Tools | Options and locate the template under ..'_o~Ka
* the Source Creation and Management node. Right-click the template and choose /,Re"!jh
* Open. You can then make changes to the template in the Source Editor. j+v=Ul|l
*/ [!]2djc
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package com.tot.count; O~K>4ax
import tot.db.DBUtils; {
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import java.sql.*; ve2u=eQ1
/** T\>a!
* .O}%
* @author dP]\Jo=Yh
*/ `W/>XZl+t
public class CountControl{ >{J(>B\
private static long lastExecuteTime=0;//上次更新时间 :mn>0jK,N
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 g:Xhw$x9
/** Creates a new instance of CountThread */ :\7X}n*&
public CountControl() {} <.izVD4/Gg
public synchronized void executeUpdate(){ 56-dD5{hxR
Connection conn=null; xCl1g4N
PreparedStatement ps=null; =uYYsC\T
try{ !Bq3Z?xA}
conn = DBUtils.getConnection(); {w^+\]tC
conn.setAutoCommit(false); +8d1|cB"
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); vbe|hO""
for(int i=0;i<CountCache.list.size();i++){ 6?~"V
CountBean cb=(CountBean)CountCache.list.getFirst(); #O}
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CountCache.list.removeFirst(); 0-yp,G
ps.setInt(1, cb.getCountId()); .j<]mUY
ps.executeUpdate();⑴ TXvI4"&
//ps.addBatch();⑵ "v({,
} ~=RT*>G_
//int [] counts = ps.executeBatch();⑶ @x'"~"%7b
conn.commit(); [o+q>|q
}catch(Exception e){ TOXfWEU3>
e.printStackTrace(); e)#J1(j_
} finally{ c*L\_Vx+
try{ iq( E'`d
if(ps!=null) { 6){]1h"
ps.clearParameters(); e-#BDN(O
ps.close(); ^pF&`2eD
ps=null; QD*35Y!d
} [dIXR
}catch(SQLException e){} !1 8clL
DBUtils.closeConnection(conn); ll.N^y;a
} Jx7C'~,J
} ~T,c"t2
public long getLast(){ }"PU%+J
return lastExecuteTime; 8sTp`}54J
} (I{rLS!o,L
public void run(){ ZE=Sp=@)j
long now = System.currentTimeMillis(); K<qk.~
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if ((now - lastExecuteTime) > executeSep) { (UvM@]B
//System.out.print("lastExecuteTime:"+lastExecuteTime); q[W
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//System.out.print(" now:"+now+"\n"); Q&=w_Wc
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); jun_QiU:2
lastExecuteTime=now; 1A G<$d5U|
executeUpdate(); $ig0j`
} D" rK(
else{ T)TfB(
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ~8P!XAU56%
} "(z5{z?S
} vyX\'r.~7
} r6}
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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 Q)"Nu.m
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类写好了,下面是在JSP中如下调用。 v>Yb/{A
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<% v|%Z+w
CountBean cb=new CountBean(); fS [,vPl
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); kG@@ot" n
CountCache.add(cb); *|>d
out.print(CountCache.list.size()+"<br>"); ;HJLs2bP
CountControl c=new CountControl(); P.;aMRMR
c.run(); u:gN?O/G
out.print(CountCache.list.size()+"<br>"); ?DQsc9y
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