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: <+3-(&
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CountBean.java u?xXZ]_u-
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/* s[2>r#M
* CountData.java s\/$`fuhx
* JA!?vs
* Created on 2007年1月1日, 下午4:44 >/J!:Htk+K
* S~GL_#a
* To change this template, choose Tools | Options and locate the template under <e)u8+(
* the Source Creation and Management node. Right-click the template and choose &-R(u}m-F
* Open. You can then make changes to the template in the Source Editor. mqrV:3}
*/
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package com.tot.count; J) I|Xot
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/** L@VIC|~E
* SyL:=NZ
* @author 7gxC
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*/ 8r{:di*
public class CountBean { BU;o$"L
private String countType; VUd=|$'J
int countId; 9=o;I;I
/** Creates a new instance of CountData */ v#Xl
public CountBean() {} F4:giu ht
public void setCountType(String countTypes){ #]SiS2lM#
this.countType=countTypes; x b6X8:
} 'cgB$:T}.,
public void setCountId(int countIds){ YZ\a#s,0
this.countId=countIds; 4;;K1< 1
} `514HgR
public String getCountType(){ OK8|w]-A
return countType; 2WF7^$^:
} o W<Z8s;p
public int getCountId(){ zqJ0pDS
return countId; +5<]s+4T
} X<p'&
} xQKRUHDc
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CountCache.java JbR;E`8
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/* -h%!#g
* CountCache.java a Byetc88/
* 9fhgCu]$
* Created on 2007年1月1日, 下午5:01 Ul{{g$
* Fi3k
* To change this template, choose Tools | Options and locate the template under q\uzmOh
* the Source Creation and Management node. Right-click the template and choose #t8{z~t3
* Open. You can then make changes to the template in the Source Editor. )}3!iDA
*/ xPp\OuwK
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package com.tot.count; 1w~@'ZyU
import java.util.*; I%?ia5]H
/** mN^/
* '.$va<
* @author f=,(0ygt/
*/ f%gdFtJ &
public class CountCache { /\-iV)h1@
public static LinkedList list=new LinkedList(); ]
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/** Creates a new instance of CountCache */ :i};]pR
public CountCache() {} 8`]1Nt!*B
public static void add(CountBean cb){ $>*TO1gb+
if(cb!=null){ Y;I>rC(
list.add(cb); P(|+1$#[
} n`TXmg
} Pbo759q1
} }K3!ujvR
}.S4;#|hw
CountControl.java n97pxD_74
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/* 0D.qc8/V4.
* CountThread.java l!7O2Ai5
* 77?D
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* Created on 2007年1月1日, 下午4:57 7#pu(:T$
* aMq|xHZ
* To change this template, choose Tools | Options and locate the template under ]IQ`.:g=9
* the Source Creation and Management node. Right-click the template and choose vj#Y /B
* Open. You can then make changes to the template in the Source Editor. 7Z7e}|
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*/ jM07&o]D
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package com.tot.count; z%0'v`7
import tot.db.DBUtils; &aLelJ~
import java.sql.*; 9snc
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/** %Bf;F;xuB
* B\mRHV!
* @author DnI31!+y
*/ G9qN1q~
public class CountControl{ E9]\ I>v
private static long lastExecuteTime=0;//上次更新时间 `{v!|.d<
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 8~@?cy1j!
/** Creates a new instance of CountThread */ 'Z{_ws
public CountControl() {} 8p0ZIrD%
public synchronized void executeUpdate(){ G\4*6iw:
Connection conn=null; l2|[
PreparedStatement ps=null; , b;WCWm
try{ GUH-$rA
conn = DBUtils.getConnection(); yd+.hg&J
conn.setAutoCommit(false); N)0V6q"
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); -qW[.B
for(int i=0;i<CountCache.list.size();i++){ sCrOdJ6|
CountBean cb=(CountBean)CountCache.list.getFirst(); yzH[~O7
CountCache.list.removeFirst(); D.;iz>_}Y
ps.setInt(1, cb.getCountId()); RASPOc/]
ps.executeUpdate();⑴ 1RM@~I$0
//ps.addBatch();⑵ Smc=-M}
} c7R<5f
//int [] counts = ps.executeBatch();⑶ zu52]$Vj
conn.commit(); H5J1j*P<d
}catch(Exception e){ qy\Z2k
e.printStackTrace(); W[4 V#&Z
} finally{ "MX9h }7
try{ 9Z!|oDP-
if(ps!=null) { [!'fE#"a
ps.clearParameters(); j8[RDiJ
ps.close(); 4apy {W
ps=null; Yn+d!w<3:
} /t=Fx94
}catch(SQLException e){} X:kqX[\>
DBUtils.closeConnection(conn); q37d:Hp
} |%~Zo:Q<$>
} l'm\*=3
public long getLast(){ 1Ax{Y#<
return lastExecuteTime; \:Vm7Zg
}
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public void run(){ 24b?6^8~k
long now = System.currentTimeMillis(); U5!~@XjG>
if ((now - lastExecuteTime) > executeSep) { P+2@,?9#
//System.out.print("lastExecuteTime:"+lastExecuteTime); p?idl`?^3
//System.out.print(" now:"+now+"\n"); ih\=mB
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ra]lC7<H
lastExecuteTime=now; c80!Ub@
executeUpdate(); WMk;-,S!)
} `"RT(` m
else{ }Y`D^z~
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ?j^:jV
} [==x4Nb
} FA7q
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} U,7O{YM
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 3<A$lG
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类写好了,下面是在JSP中如下调用。 *w,C5 f
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<% `~;`q
CountBean cb=new CountBean(); 0CR~ vQf#r
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); C>~ms2c
CountCache.add(cb); zNRR('B?
out.print(CountCache.list.size()+"<br>"); HpGI\s
CountControl c=new CountControl(); Zv|TvlyT"
c.run(); Uw5AHq).
out.print(CountCache.list.size()+"<br>"); K}a3Bj,
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