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: mBhG"0:
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CountBean.java cx&jnF#$
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/* `QC{}Oo^
* CountData.java n1a;vE{!
* ~*ZB2
* Created on 2007年1月1日, 下午4:44 kb Fr
* $oHlfV/!
* To change this template, choose Tools | Options and locate the template under L/1?PM
* the Source Creation and Management node. Right-click the template and choose 89Svx5S
* Open. You can then make changes to the template in the Source Editor. k
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*/ S92'\2
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package com.tot.count; 8G?'F${`
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/** &^8>Kd8
* #%il+3J
* @author ]m{;yOQdsC
*/ r3mB"("Z'
public class CountBean { tV9BVsN
private String countType; $Ud-aRlD
int countId; @ZK#Y){
/** Creates a new instance of CountData */ $M@SZknm
public CountBean() {} fJtJ2x i
public void setCountType(String countTypes){ }"06'
this.countType=countTypes; ZsirX~W<
} j/5>zS
public void setCountId(int countIds){ ,]w-!I
this.countId=countIds; :(c2YZ
} aBj~370g
public String getCountType(){ JR<#el
return countType; ;<1O86!
} R|Z $aHQ
public int getCountId(){ E<1^i;F
return countId; !:,d^L!bh
} kZs
} ?g&6l0n`
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CountCache.java y/K% F,WMf
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/* t48(,
* CountCache.java i,NN"
* N'+d1
* Created on 2007年1月1日, 下午5:01 L[)+J2_<
* 2T<QG>;)j
* To change this template, choose Tools | Options and locate the template under URck#5
* the Source Creation and Management node. Right-click the template and choose ps[TiW{q;
* Open. You can then make changes to the template in the Source Editor. g2l|NI#c^
*/ mHE4Es0
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package com.tot.count; s03DL
import java.util.*; .^N+'g
/** KW+ps16~
* S3PW [R@=
* @author W1f]A#t<
*/ S ])YU?e
public class CountCache { .J#xlOa-
public static LinkedList list=new LinkedList(); AMA:hQ
/** Creates a new instance of CountCache */ 1!/cd;{B
public CountCache() {} ;LELC5[*s
public static void add(CountBean cb){ yHLclv
if(cb!=null){ >P/kb fPA
list.add(cb); A0# K@
} eC%.xu^
} 9aD6mp
} ZalG/PFy
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CountControl.java j9XY%4.
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/* ,miU'<8tQ|
* CountThread.java ~O?Gi 4^Yg
*
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* Created on 2007年1月1日, 下午4:57 )fP,F(
* cBb!7?6(
* To change this template, choose Tools | Options and locate the template under fz31di9$
* the Source Creation and Management node. Right-click the template and choose 8)&yjY
* Open. You can then make changes to the template in the Source Editor.
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*/ #M&rmKv)g
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package com.tot.count; 7=0uG
import tot.db.DBUtils; .!RBhLH_g
import java.sql.*; PA5ET@mD
/** MI0'ou8l
* s<5q%5ix3
* @author SE)_5|k*
*/ =H.l/'/Z
public class CountControl{ z11;r]VI
private static long lastExecuteTime=0;//上次更新时间 S,fMGKcq
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 Za}*6N=?*
/** Creates a new instance of CountThread */ .+]e9mV
public CountControl() {} *E+2E^B
public synchronized void executeUpdate(){ }OJ*o
Connection conn=null; @=h%;"
PreparedStatement ps=null; @4^5C-
try{ >~_y\
conn = DBUtils.getConnection(); 9G` 2t~%
conn.setAutoCommit(false); h']RP
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); YN_#x
for(int i=0;i<CountCache.list.size();i++){ RQWVjF#
CountBean cb=(CountBean)CountCache.list.getFirst(); t }7hD
CountCache.list.removeFirst(); PwQW5,,h0
ps.setInt(1, cb.getCountId()); q<o*rcwf^
ps.executeUpdate();⑴ 7)O?jc
//ps.addBatch();⑵ vnMt>]w-}
} 3hab51J
//int [] counts = ps.executeBatch();⑶ k:4 Zc3
conn.commit(); >};,Byv!%
}catch(Exception e){ ~`
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e.printStackTrace(); e'[T5HI
} finally{ *#;8mM
try{ )|@b
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if(ps!=null) { A@bWlwfl
ps.clearParameters(); x9xb4ZW
ps.close(); &{9'ylv-B)
ps=null; NoO>CjeFb
} l
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}catch(SQLException e){} vP^]Y.6
DBUtils.closeConnection(conn); d#Sc4xuf
} DalQ.
} yA?>v'K
public long getLast(){ xr&wV0O'
return lastExecuteTime; fO[X<|9
} `J[(Dx'y=t
public void run(){ G]E$U]=9r:
long now = System.currentTimeMillis(); V.)y7B
if ((now - lastExecuteTime) > executeSep) { @;qC% +^
//System.out.print("lastExecuteTime:"+lastExecuteTime); {S%)GvrT
//System.out.print(" now:"+now+"\n"); yT`[9u,
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 0aQtJ0e16
lastExecuteTime=now; kFgN^v^t
executeUpdate(); 6[$kEKOY=
} wYSvI
else{ 4q/E7n
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); Fkuq'C<|Y
} D;Fvd:
} >9a%"<(2#
} V]L$`7G
//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 2FD[D`n]f
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类写好了,下面是在JSP中如下调用。 s=(~/p#M
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<% kQC>8"
CountBean cb=new CountBean(); B}X
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); N?Mmv|
CountCache.add(cb); 7U:,:=
out.print(CountCache.list.size()+"<br>");
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CountControl c=new CountControl(); (9';zw
c.run(); LeO
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out.print(CountCache.list.size()+"<br>"); Qc;`nck
%>