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: gNt(,_]ZR
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CountBean.java Ii G6<|d8H
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/* 6i1LjLB
* CountData.java 6Vz9?puD
* 6I%5Q4Ll
* Created on 2007年1月1日, 下午4:44 AvfNwE
* j KoG7HH
* To change this template, choose Tools | Options and locate the template under .ev?"!Vpp9
* the Source Creation and Management node. Right-click the template and choose gP;&e:/3
* Open. You can then make changes to the template in the Source Editor. K*~0"F>"0
*/ YJ\Xj56gv
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package com.tot.count; m6w].-D8
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/** [Al&
* b45-:mi!
* @author ,^2>k3=
*/ ev*k*0
public class CountBean { sVOyT*GY
private String countType;
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int countId; nCdR EXw
/** Creates a new instance of CountData */ `Tv[DIVW
public CountBean() {} c}2jmwq
public void setCountType(String countTypes){ >s<^M|S07
this.countType=countTypes; Zcx`SC-0
} wY[+ZT
public void setCountId(int countIds){ .oeX"6K
this.countId=countIds; iMDM1}b
} Q o{/@
public String getCountType(){ 1=d6NX)B
return countType; U_I5fK=
} ^LoUi1j
public int getCountId(){ <+?7H\b
return countId; 8|l\EVV6
} b?tB(if!I
} Ng~FEl
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CountCache.java /rnu<Q#iH
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/* s@K4u^$A
* CountCache.java .$+#1-
* 61k"p2?+
* Created on 2007年1月1日, 下午5:01 0=2@
* b*c*r dTx
* To change this template, choose Tools | Options and locate the template under TJ6*t!'*X
* the Source Creation and Management node. Right-click the template and choose A>o*t=5
* Open. You can then make changes to the template in the Source Editor. uxvqMgR
*/ +0nJ
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package com.tot.count; EyJJ0
import java.util.*; (X\@t-8
/** \fz<.l]
* A$Hfr8w1u
* @author dx MOn
*/ jCOIuw
public class CountCache {
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public static LinkedList list=new LinkedList(); 5YE'L.
/** Creates a new instance of CountCache */ -*X a3/kQ
public CountCache() {} `yrB->|vG
public static void add(CountBean cb){ S"NqM[W
if(cb!=null){ EE&K0<?T|:
list.add(cb); !Xf5e*1IS
} x<tb
} `VA"vwz
} naG=Pq<
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CountControl.java } gyj0
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/* j4gF;-m<
* CountThread.java FH?U(-
* +~m46eI
* Created on 2007年1月1日, 下午4:57 +rd|A|hRq
* 36}?dRw#p
* To change this template, choose Tools | Options and locate the template under i1ixi\P{0
* the Source Creation and Management node. Right-click the template and choose LO9=xGj.
* Open. You can then make changes to the template in the Source Editor. Z]>O+
*/ ,1~"eGl!
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package com.tot.count; ]
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import tot.db.DBUtils; !"?#6-,Xn
import java.sql.*; :3v}kLO7|
/** .F98G/s
* @K &GJ
* @author Si2k"<5U
*/ 7OcWC-<
public class CountControl{ fiK6@,
private static long lastExecuteTime=0;//上次更新时间 l:
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private static long executeSep=60000;//定义更新间隔时间,单位毫秒 $O&b``
/** Creates a new instance of CountThread */ ~Z\8UsVN
public CountControl() {} c,np2myd
public synchronized void executeUpdate(){ u@Ih GME
Connection conn=null; \pa"%c)
PreparedStatement ps=null; ]R+mKUZ9
try{ {2O1"|s ,
conn = DBUtils.getConnection(); gh/EU/~d
conn.setAutoCommit(false); a@_4PWzF:
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ~8'sBT
for(int i=0;i<CountCache.list.size();i++){ -^&<Z
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CountBean cb=(CountBean)CountCache.list.getFirst(); Zi *2nv'
CountCache.list.removeFirst(); kvL=>
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ps.setInt(1, cb.getCountId()); !j9t*2m[
ps.executeUpdate();⑴ epA:v|S
//ps.addBatch();⑵ l5S aT,%
} 5Yg'BkEr
//int [] counts = ps.executeBatch();⑶ 9'fQHwsJ
conn.commit(); Bd!bg|uO*
}catch(Exception e){ Z^bQ^zk-
e.printStackTrace(); ,;EIh}
} finally{
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try{ v,FU^f-'
if(ps!=null) { 0M_ DB=
ps.clearParameters(); h{)kQLuzT
ps.close(); ep!Rf:
ps=null; &PR5q7
} rN<0
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}catch(SQLException e){} R3
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DBUtils.closeConnection(conn); lUOF4U&r
} [T8WThs
} F%@A6'c
public long getLast(){ E-T)*`e
return lastExecuteTime; u4t7Ie*Q
} kYzIp
public void run(){ T:27r8"Rh
long now = System.currentTimeMillis(); cXA
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if ((now - lastExecuteTime) > executeSep) { Eq% }
//System.out.print("lastExecuteTime:"+lastExecuteTime); \{Y 7FC~
//System.out.print(" now:"+now+"\n"); ;"a=gr
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); p)KheLiZ
lastExecuteTime=now; QE^$=\l0
executeUpdate(); 3lf=b~Zi)
} n<Z({\9&H
else{ 2Z+Wu3#
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); |6.l7u?d
} p2hB8zL
} =mO vs
} GA$V0YQX
//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 `LrHKb
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类写好了,下面是在JSP中如下调用。 P}Gj%4/G
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<% aZH:#lUlj
CountBean cb=new CountBean(); bZ dNibN
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); @3>u@
CountCache.add(cb); f/ U`
out.print(CountCache.list.size()+"<br>"); rlML W
CountControl c=new CountControl(); j
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c.run(); mUNn%E:7@{
out.print(CountCache.list.size()+"<br>"); q_MPju&*
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