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: s(MdjWw
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CountBean.java kkj_k:Eah
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/* bW3Ah?0N
* CountData.java Ow-;WO_HQ
* GzT?I
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* Created on 2007年1月1日, 下午4:44 &kH7_Lz
* :/}=s5aQl/
* To change this template, choose Tools | Options and locate the template under S7R*R}
* the Source Creation and Management node. Right-click the template and choose HDs8 M
* Open. You can then make changes to the template in the Source Editor. t*c_70|@k
*/ QxBH{TG
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package com.tot.count; q+lCA#Sx
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/** j?!/#'
* ;$4:
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* @author ~BXy)IB6
*/ ^4{{ +G)j
public class CountBean { ,awkL
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private String countType; ^j?"0|
int countId; "YVvmCp
/** Creates a new instance of CountData */ 8BnsYy)j
public CountBean() {} Uz`OAb
public void setCountType(String countTypes){ )/bv@Am
this.countType=countTypes; `3dGn.M
} 4HGR-S/
public void setCountId(int countIds){ *uF Iw}C/
this.countId=countIds; yJ8_<A
} 2]tW&y_i
public String getCountType(){
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return countType; 4&B|rf
} 3gW+|3E
public int getCountId(){ \Oe8h#%
return countId; m;u :_4
} p.vxrk`c
} +a'nP=e&
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CountCache.java 1]7v3m
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/* NcIr;
}
* CountCache.java {=P}c:iW
* k_ijVfI9
* Created on 2007年1月1日, 下午5:01 1_)Y{3L
* N9O}6
* To change this template, choose Tools | Options and locate the template under |b|bL 7nx
* the Source Creation and Management node. Right-click the template and choose .gw6W0\F
* Open. You can then make changes to the template in the Source Editor. u9ue>I/
*/ %lGg}9k'
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package com.tot.count; <!~NG3KW[>
import java.util.*; I$I',x5Z
/** pA@BW:#
* =o4McV}
* @author HgOrrewj
*/ nD{{/_"'
public class CountCache { 6W N(Tw
public static LinkedList list=new LinkedList(); <+ckE2j
/** Creates a new instance of CountCache */ Jrx]/CM
public CountCache() {} 2L7ogyrU/A
public static void add(CountBean cb){ ujbJ&p
if(cb!=null){ ^W[3RiG
list.add(cb); 8s6^!e&
} x)e(g}n
} IjRUL/\=
} ,<=_t{^
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CountControl.java TiSV`V q
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/* ~P+;_
* CountThread.java Kl*/{&,P
*
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* Created on 2007年1月1日, 下午4:57 :n$?wp
* gPy}.g{tH$
* To change this template, choose Tools | Options and locate the template under UAtdRVi]M
* the Source Creation and Management node. Right-click the template and choose &=v5M9GR]
* Open. You can then make changes to the template in the Source Editor. r%` |kN
*/ 6Zq7O\
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package com.tot.count; w)%/Me3o
import tot.db.DBUtils; Z(o]8*;Ai
import java.sql.*; vA0f4W 8+
/** \.{ZgL5"
* #|acRZ9
}
* @author *uvE`4V^Jg
*/ 1IZTo!xi
public class CountControl{ @s~*>k#"#
private static long lastExecuteTime=0;//上次更新时间 OG2&=~hOz-
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 `:EU~4s\
/** Creates a new instance of CountThread */ g42Z*+P6N
public CountControl() {} WlnS.P\+E
public synchronized void executeUpdate(){ 5s1XO*s)>X
Connection conn=null; =-n7/
PreparedStatement ps=null; D
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try{ p!2t/XIM
conn = DBUtils.getConnection(); $3{I'r]
conn.setAutoCommit(false); 420yaw/":
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); +cx(Q(HD\
for(int i=0;i<CountCache.list.size();i++){ U7d05y'
CountBean cb=(CountBean)CountCache.list.getFirst(); #i[V{J8.p
CountCache.list.removeFirst(); jI,?*n<
ps.setInt(1, cb.getCountId()); &%` 0&y
ps.executeUpdate();⑴ &W-1W99auE
//ps.addBatch();⑵ .oxeo0@~
} \Gz
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//int [] counts = ps.executeBatch();⑶ 17B`
conn.commit(); XQ$9E?|=
}catch(Exception e){ kaZ_ra;<
e.printStackTrace(); [fr!J?/@
} finally{ bn0Rv
try{ ak]H|D" 9
if(ps!=null) { h
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ps.clearParameters(); A7sva@}W
ps.close(); Rln@9muXA
ps=null; ;v>+D
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} ' |
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}catch(SQLException e){} XFWo"%}w
DBUtils.closeConnection(conn); hwd{^
} </)QCl' d
} h&:6S
public long getLast(){ 3d*wZ9qz
return lastExecuteTime; gatxvR7H
} wTPHc:2
public void run(){ %2EHYBQjN
long now = System.currentTimeMillis(); .vhEm6wJUM
if ((now - lastExecuteTime) > executeSep) { Kma-W{vGD
//System.out.print("lastExecuteTime:"+lastExecuteTime); t
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//System.out.print(" now:"+now+"\n"); $o>6Io|D
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); yU< "tg E
lastExecuteTime=now; qq[Enf|/y
executeUpdate(); <l"rn M%
} T{mIkp<
else{ VfJdCg_
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ^<QF*!
}
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} 4+4C0/$Y
} pJPP6Be<
//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 iVqXf;eB!5
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类写好了,下面是在JSP中如下调用。 |A19IXZ\
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<% Xrd-/('2
CountBean cb=new CountBean(); )5U2-g#U
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); %~^:[@xa*
CountCache.add(cb); ~U`|+
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out.print(CountCache.list.size()+"<br>"); XZ[3v9?&n
CountControl c=new CountControl(); iE=:}"pI"
c.run(); V( SRw
out.print(CountCache.list.size()+"<br>"); (ixlFGvEq
%>