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: "B__a(
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CountBean.java j7g>r/1eE
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/* /!Ag/SmS!9
* CountData.java Z:h'kgG &
* sqhIKw@
* Created on 2007年1月1日, 下午4:44 63\
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* j-J/yhWO&
* To change this template, choose Tools | Options and locate the template under [g"nu0sOK
* the Source Creation and Management node. Right-click the template and choose NKFeND
* Open. You can then make changes to the template in the Source Editor. U+B{\38
*/ ] rqx><!
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package com.tot.count; g ;
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/** Xbx=h^S
* mvpcRe
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* @author Fg
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*/ u{uqK7]+
public class CountBean { 90abA,U@
private String countType; <nk/w5nKL
int countId; #o~C0`8!B=
/** Creates a new instance of CountData */ %?V~7tHm>
public CountBean() {} _M8'~$Sg
public void setCountType(String countTypes){ DQu)?Rsk
this.countType=countTypes; s^PsA9EAn
} 9UteD@*
public void setCountId(int countIds){ <6.`(isph
this.countId=countIds; %=K [C
} "+O/OKfR0
public String getCountType(){ _Ad63.Uq))
return countType; h]i vXF*
} XkUwO ]
public int getCountId(){ yZ=O+H
return countId; &QQ6F>'T
} %b_0l<+
} 6j1C=O@S
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CountCache.java H0B=X l[
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/* *@@dO_%6
* CountCache.java "-:g.x*d
* j)ln"u0R^B
* Created on 2007年1月1日, 下午5:01 "tJ[M
* vY4}vHH2
* To change this template, choose Tools | Options and locate the template under WyB^b-QmDh
* the Source Creation and Management node. Right-click the template and choose mcQ
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* Open. You can then make changes to the template in the Source Editor. <ir]bQT
*/ By[M|4a
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package com.tot.count; :>ca).cjac
import java.util.*; b O}&i3.L;
/** k]-Q3V
* ;c|_z 9+
* @author ^XYK
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*/ +>yh`Zb
public class CountCache { yoieWnL}
public static LinkedList list=new LinkedList(); <7Yh<(R e^
/** Creates a new instance of CountCache */ keQRS+9
public CountCache() {} t<}N>%ZO
public static void add(CountBean cb){ k=p[Mlic/
if(cb!=null){ t5 ^hZZ
list.add(cb); rR{KnM
} CO,{/
} B )\;Ja
} q TWQ!
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CountControl.java f#I#24)RH
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/* G"L`9E<0V
* CountThread.java 3,hu3"@k
* ]M "U 'Z
* Created on 2007年1月1日, 下午4:57 ^HuB40
* 4kV$JV.l
* To change this template, choose Tools | Options and locate the template under
(t@!0_5
* the Source Creation and Management node. Right-click the template and choose N?,
* Open. You can then make changes to the template in the Source Editor. BVus3Y5IJQ
*/ BSr#;;\
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package com.tot.count; H<nA*Zf2@R
import tot.db.DBUtils; XN\rq=
import java.sql.*; # Rs5W
/** .*+jD^Gr
* T~XKV`LQ
* @author 3)e{{]6
*/ kQ2WdpZ/
public class CountControl{ <dXeP/1w`
private static long lastExecuteTime=0;//上次更新时间 I+3=|Vef
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 fX\y/C
/** Creates a new instance of CountThread */ qv:DpK
public CountControl() {} |RXXj [z
public synchronized void executeUpdate(){ o1{3[=G
Connection conn=null; 2zv:j7
PreparedStatement ps=null; |h/{qpsu
try{ K0I.3|6C
conn = DBUtils.getConnection(); >s.y1Vg~C
conn.setAutoCommit(false); CZy3]O"qW
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); g{>0Pa1?C
for(int i=0;i<CountCache.list.size();i++){ .Tw:Y,G
CountBean cb=(CountBean)CountCache.list.getFirst(); V`c,U7[/
CountCache.list.removeFirst(); Ut/%+r"s
ps.setInt(1, cb.getCountId()); .>}Z3jUrf
ps.executeUpdate();⑴ 8y[Rwa
//ps.addBatch();⑵ #l9sQ-1Q
} &(p5z4Df
//int [] counts = ps.executeBatch();⑶ pnL[FMc
conn.commit(); Ll#W:~
}catch(Exception e){ r AqS;@]0
e.printStackTrace(); QaA?UzB
} finally{ 5xj8^W^G9
try{ "So"oT1
if(ps!=null) { (?GW/pLK]
ps.clearParameters(); /Q89 y[
ps.close(); z7P~SM
ps=null; OP=-fX|*Q
} dd
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}catch(SQLException e){} +T,A^(&t
DBUtils.closeConnection(conn); w7q6v>
} #IDLfQ5g
} Oi@|4mo
public long getLast(){ g2M1zRm;
return lastExecuteTime; 2BT+[
} NweGK
public void run(){ :>H{?
long now = System.currentTimeMillis(); 'w<^4/L Q
if ((now - lastExecuteTime) > executeSep) { V_ntS&2o
//System.out.print("lastExecuteTime:"+lastExecuteTime); )
jM-5}"
//System.out.print(" now:"+now+"\n"); Be^"sC
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); Cy5iEI#
lastExecuteTime=now; 0pH$MkQ
executeUpdate(); Y;E'gP-J
} 7A$mZPKh
else{ Z0XQ|gkH
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); /L|x3RHs
} YV>&v.x0;
} 497 l2}0
} V pY,@qh
//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 }w>UNGUMh
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类写好了,下面是在JSP中如下调用。 gv(MX
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<% &
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CountBean cb=new CountBean(); Es\J%*\u
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); c]$$ap
CountCache.add(cb); \TDn q!)?
out.print(CountCache.list.size()+"<br>"); :C0)[L
CountControl c=new CountControl(); )U]q{0`
c.run(); ,KPrUM}
out.print(CountCache.list.size()+"<br>"); m?8o\|i,
%>