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: *Ag, kW"
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CountBean.java Ut=0~x.=<
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/* c'[( d5^|
* CountData.java gGD]t;<u
* 8^NE=)cb7w
* Created on 2007年1月1日, 下午4:44 {S# 5g2
* 9Z}S]-u/
* To change this template, choose Tools | Options and locate the template under vV2o[\o^
* the Source Creation and Management node. Right-click the template and choose i@%L_[MtA
* Open. You can then make changes to the template in the Source Editor. f61]`@Bk
*/ 7YSuB9{M
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package com.tot.count; @)8NI[=6O
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/** ;%lJD"yF
* HM;4=%
* @author :1%VZvWk*
*/ y;*My#
public class CountBean { 8VKb*
private String countType; A89Y;_4y
int countId; "4k"U1
/** Creates a new instance of CountData */ vQE` c@^{
public CountBean() {} ..sJtA8
public void setCountType(String countTypes){ _q2`m
this.countType=countTypes; ^!XU+e+:0
} w`2_6[,9
public void setCountId(int countIds){ q
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this.countId=countIds; V/+H_=|
} @|JPE%T
public String getCountType(){ X:iG[iU*
return countType; w/)e2CH
} |rG8E;>
public int getCountId(){ sf=%l10Fk#
return countId; 'lSnyW{
}
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} Ta!m%=8
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CountCache.java exGhkt~
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/* x|P<F 2L
* CountCache.java U:C-\ M
* [U_Q 2<H
* Created on 2007年1月1日, 下午5:01 ?}!gLp
* IDL^0:eg<.
* To change this template, choose Tools | Options and locate the template under \ZmFH8=|f
* the Source Creation and Management node. Right-click the template and choose h[M6.
* Open. You can then make changes to the template in the Source Editor. ~`W6O>
*/ #Q!c42}M
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package com.tot.count; 3<Pyr-z h
import java.util.*; X8NO;w@z#
/** ".Q!8j"@f
* h<!khWFS
* @author -hJ>wGI
*/ 8/kx 3
public class CountCache { 519:yt
public static LinkedList list=new LinkedList(); qJAv=D
/** Creates a new instance of CountCache */ -sGWSC
public CountCache() {} hIg, 0B
public static void add(CountBean cb){ E?;T:7.%
if(cb!=null){ d"e%tsj
list.add(cb); 0wa!pE"
} nP3;<*T P0
} +X|m>9
} HK,G8:T
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CountControl.java `!>dbR&1
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/* W;)FNP|MT
* CountThread.java r>:7${pF
* =-s20mdj
* Created on 2007年1月1日, 下午4:57 E?c{02fu
* o-e,
* To change this template, choose Tools | Options and locate the template under ^Hhw(@`qf
* the Source Creation and Management node. Right-click the template and choose > Qbc(}w
* Open. You can then make changes to the template in the Source Editor. lN`_0
*/ ,B/p1^;.
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package com.tot.count; Pk?%PB?Z
import tot.db.DBUtils; >a`zkl
import java.sql.*; A>1p]#
/** cTIwA:)D
* H*
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* @author oTV8rG
*/ ,IZxlf%
public class CountControl{ r(2'0JQ
private static long lastExecuteTime=0;//上次更新时间 O[(HE8E
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 f/WM}Hpj
/** Creates a new instance of CountThread */ JLV}Fw
public CountControl() {} W<hdb!bE
public synchronized void executeUpdate(){ { )GEgC
Connection conn=null; SUi1*S
PreparedStatement ps=null; C.e|VzQa
try{ D>#v 6XI
conn = DBUtils.getConnection(); %oL&~6l$
conn.setAutoCommit(false); Rc.<0#
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); #vZ]2Ud=2
for(int i=0;i<CountCache.list.size();i++){ {F9Qy0.*u
CountBean cb=(CountBean)CountCache.list.getFirst(); G~hILW^
CountCache.list.removeFirst(); wj5s5dH
ps.setInt(1, cb.getCountId()); 'e)ze^Jq
ps.executeUpdate();⑴ Gv
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//ps.addBatch();⑵ ?9okjLp1n
} HNUR6H&Fta
//int [] counts = ps.executeBatch();⑶ oYm{I ~"
conn.commit(); IV#My9}e
}catch(Exception e){ hA1hE?c`
e.printStackTrace(); 1~u\]Zi=D
} finally{ xr3PO?:
try{ &OR*r7*Z
if(ps!=null) { 4k?JxA)
ps.clearParameters(); WuZn|j'
ps.close(); [)6E)E`_e
ps=null; n~i4yn=
}
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}catch(SQLException e){} R.'Gg
DBUtils.closeConnection(conn); c(g^*8Pb
} n.UM+2G
} [a*>@IR
public long getLast(){
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return lastExecuteTime; (gC^5&11
} ~e~Mx=FT0
public void run(){ ^M5uLm-_s
long now = System.currentTimeMillis(); rL/7wa
if ((now - lastExecuteTime) > executeSep) { I2!HXMrp
//System.out.print("lastExecuteTime:"+lastExecuteTime); E1w XG
//System.out.print(" now:"+now+"\n"); ZGvNEjff
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); >ZsK5v
lastExecuteTime=now; +Z(VWu6
executeUpdate(); Xn'>k[}<k
} ?\VN`8Yb
else{ !7*/lG
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); CPM6T$_qE
} nW*Oo|p~=
} ~mo`
} z{WqICnb
//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 yvwcXNXR@
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类写好了,下面是在JSP中如下调用。 Fa^]\:
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<% Vo8"/]_h
CountBean cb=new CountBean(); VO?NrKyeW
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); "evV/Fg(
CountCache.add(cb); >9|+F[Fc
out.print(CountCache.list.size()+"<br>"); 7Wn]l!
CountControl c=new CountControl(); UeQ%(f
c.run(); W4a20KM2
out.print(CountCache.list.size()+"<br>"); {Vu:yh\<
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