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: U^Hymgb%
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CountBean.java qk<tLvD_'
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/* 0Wk}d(f
* CountData.java >6(nW:I0y
* t7n*kiN<q
* Created on 2007年1月1日, 下午4:44 Lw-)ijBW
* AEEy49e
* To change this template, choose Tools | Options and locate the template under 3WaYeol`
* the Source Creation and Management node. Right-click the template and choose -6Cxz./#yS
* Open. You can then make changes to the template in the Source Editor. lQ)ZsFs=
*/ [NJ!
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package com.tot.count; $] w&`F-
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/** *bwLih!}H
* U4M!RdG
* @author ~)WE
*/ AnI ENJ
public class CountBean { 6\'v_A
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private String countType; =q>eoXp
int countId; u:fiil$
/** Creates a new instance of CountData */ ~vG~Z*F
public CountBean() {} Le#bitp
public void setCountType(String countTypes){ MNkysB(
this.countType=countTypes; ^D/*Hp _
} sL[,J[AN;
public void setCountId(int countIds){ 0
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this.countId=countIds; ;J2=6np
} jG8ihi
public String getCountType(){ M="%NxuS
return countType; Mx[tE?!2
} TQYud'u/
public int getCountId(){ a\^DthZ!;|
return countId; oZP:}= F
} =suj3.
} NCX!ss
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CountCache.java wGAN"K:e
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/* 4*d_2:|u
* CountCache.java ;k!bv|>n
* ,SS@]9A&
* Created on 2007年1月1日, 下午5:01 c\"oj&>A
* j{S\X'?
* To change this template, choose Tools | Options and locate the template under ~ia#=|1}
* the Source Creation and Management node. Right-click the template and choose @(&ki~+
* Open. You can then make changes to the template in the Source Editor. lvcX}{>\
*/ 0 UjT<t^F
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package com.tot.count; ?OlYJ/!z3
import java.util.*; # 1I<qK
/**
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* *>zr'Tt,W
* @author $OmcEd
*/ +X"TiA7{j
public class CountCache { cfa#a!Y4
public static LinkedList list=new LinkedList(); F(}d|z@@
/** Creates a new instance of CountCache */ 2}'&38wMT
public CountCache() {} >"N \ZC^
public static void add(CountBean cb){ !#g`R?:g
if(cb!=null){ lg;`I tX]
list.add(cb); 5|&Sg}_
} s
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} @ U:WWTzf
} hjaI&?w
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CountControl.java jpT!di
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/* 2mVH*\D
* CountThread.java dV.)+X7<
* h$4V5V
* Created on 2007年1月1日, 下午4:57 |4x&f!%m
* ,1RW}1n
* To change this template, choose Tools | Options and locate the template under 9F ).i
* the Source Creation and Management node. Right-click the template and choose ~iydp
* Open. You can then make changes to the template in the Source Editor. *
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*/ Dbz\8gmY
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package com.tot.count; ^ D?;K8a-l
import tot.db.DBUtils; ;(TBg-LEK
import java.sql.*; {b7P1}>-*
/** .@ /5Ln
* GcHWalm
* @author a}El!7RO0
*/ ;{j:5+'
public class CountControl{ %[Ia#0'Y@
private static long lastExecuteTime=0;//上次更新时间 MoO
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private static long executeSep=60000;//定义更新间隔时间,单位毫秒 VDCrFZ!]
/** Creates a new instance of CountThread */ ezC55nm
public CountControl() {} >{ne!
public synchronized void executeUpdate(){ 0'c<EJ
Connection conn=null; I^0bEwqZ~
PreparedStatement ps=null; rQ@,Y"
try{ f+-w~cN
conn = DBUtils.getConnection(); FzFY2h;n]B
conn.setAutoCommit(false); 'R,1Jmx
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); v=iz*2+X
for(int i=0;i<CountCache.list.size();i++){ #oJ9BgDry
CountBean cb=(CountBean)CountCache.list.getFirst(); \Vr(P>
CountCache.list.removeFirst(); 1!0BE8s"@
ps.setInt(1, cb.getCountId()); >=r094<
ps.executeUpdate();⑴ kG@1jMPtQ
//ps.addBatch();⑵ e
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} 5 S7\m5
//int [] counts = ps.executeBatch();⑶ NrhU70y
conn.commit(); SN\;&(?G
}catch(Exception e){ [ wr0TbtV
e.printStackTrace(); /'!F \ kz
} finally{ /$/\$f$
try{ htkn#s~=
if(ps!=null) { :
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ps.clearParameters(); y=G
ps.close(); '~<D[](/F
ps=null; q}1AV7$Ai
} & i)p^AmM
}catch(SQLException e){} pU<->d;->
DBUtils.closeConnection(conn); 0Eo*C9FP~
} y~]>J^
} 7f~.Qus
public long getLast(){ <+
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return lastExecuteTime; ERCW5b[RT
} `?2S4lN/
public void run(){ Mpb|qGi!
long now = System.currentTimeMillis(); W5HC7o\4
if ((now - lastExecuteTime) > executeSep) { .
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//System.out.print("lastExecuteTime:"+lastExecuteTime); !E4YUEY6
//System.out.print(" now:"+now+"\n"); Ym2![FC1
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); l2X'4_d
lastExecuteTime=now; <Mxy&9}ic
executeUpdate(); %dhnp9'
} ,K,n{3]
else{ G %Wjtrpj
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 6psK2d0
} _LCK|H%v'
} f0O"Hm$Z
} vqJiMa j@Z
//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 D}&U3?g=
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类写好了,下面是在JSP中如下调用。 e#<%`\qH
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CountBean cb=new CountBean(); B14z<x}Q
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 65)/|j+
CountCache.add(cb); qI5_@[S*
out.print(CountCache.list.size()+"<br>"); o/)]z
CountControl c=new CountControl(); PL%U
c.run(); >
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out.print(CountCache.list.size()+"<br>"); >E^sZmY[f-
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