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: 5W@jfh)
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CountBean.java wL^%w9q-
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/* 4r0b)Y&I
* CountData.java Yl$SW;@
* {E0z@D)U-
* Created on 2007年1月1日, 下午4:44 b(I2m
* PeE/iZ.
* To change this template, choose Tools | Options and locate the template under .*JA!B
* the Source Creation and Management node. Right-click the template and choose F5qFYL;
* Open. You can then make changes to the template in the Source Editor. @b3#X@e}
*/ }Lw>I94e
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package com.tot.count; T'aec]u
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/** {?}*1,I
* *8tI*Pus
* @author cFF*Z=L_
*/ 9A7@
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public class CountBean { "h7tnMS
private String countType; )
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int countId; *cg(
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/** Creates a new instance of CountData */ S"hTE7`
public CountBean() {} S$^RbI
public void setCountType(String countTypes){ GzTq5uU&
this.countType=countTypes; X*7\lf2
} @AYo-gf
public void setCountId(int countIds){ )CS.F=
this.countId=countIds; `K
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} oo$MWN8a>r
public String getCountType(){ o(Cey7
return countType; 02k4N%
} xlR2|4|8
public int getCountId(){ 35x 0T/8
return countId; hwDbs[:
} X5*C+ I=2
} ow' lRHZ
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CountCache.java ]k8/#@19
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/* Kw`VrcwjT
* CountCache.java eb8w~
* s$*'^:
* Created on 2007年1月1日, 下午5:01 x)_@9ldYv
* m%8qZzqk
* To change this template, choose Tools | Options and locate the template under DBs*Fx[
* the Source Creation and Management node. Right-click the template and choose 1]T`n /d V
* Open. You can then make changes to the template in the Source Editor. 2qO3XI
*/ {3Vk p5%l
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package com.tot.count; w_iam qe,
import java.util.*; CC3v%^81l^
/** l#wdpD a{
* h
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* @author zK+52jhi
*/ OW(&s,|6x
public class CountCache { Ih[+K#t+E
public static LinkedList list=new LinkedList(); Zzl,gy70
/** Creates a new instance of CountCache */ -)y%~Zn
public CountCache() {} ib0g3p-Lc
public static void add(CountBean cb){ W];EKj,3W
if(cb!=null){ &wetzC)
list.add(cb); BD#.-xWV
} e|r0zw S
} ARfRsPxr
} k 2%S`/:
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CountControl.java cxYfZ4++m
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/* L {ymI)Y^
* CountThread.java XO
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* #m8sK(#lo
* Created on 2007年1月1日, 下午4:57 p'{xoV
* })IO#,
* To change this template, choose Tools | Options and locate the template under W:QwHZ2O
* the Source Creation and Management node. Right-click the template and choose C+MSVc
* Open. You can then make changes to the template in the Source Editor. XDD<oo
*/ wp.TfKxw
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package com.tot.count; <Jp1A#
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import tot.db.DBUtils; e^$j5jV
import java.sql.*; IGAzE(
/** 4o9$bv
* I2HT2c$
* @author Cj;/Uhs
*/ rFL$QC2
public class CountControl{ 396R$\q
private static long lastExecuteTime=0;//上次更新时间 5GAy "Xd
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 emA!Ew(g
/** Creates a new instance of CountThread */ (5uJZ!m
public CountControl() {} :a<hQ|p
public synchronized void executeUpdate(){ } IlP:
Connection conn=null; ]5v:5:H
PreparedStatement ps=null; hQgN9S5P
try{ q?~Rnv
conn = DBUtils.getConnection(); ZcryAm:I
conn.setAutoCommit(false); /axTh
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); QlW=_Ymv{
for(int i=0;i<CountCache.list.size();i++){ <kD#SV%"
CountBean cb=(CountBean)CountCache.list.getFirst(); y?N Nz0
CountCache.list.removeFirst(); LN!W(n(
ps.setInt(1, cb.getCountId()); `!w^0kZ
ps.executeUpdate();⑴ 8t.dPy<
//ps.addBatch();⑵ N)43};e
} LI:Tc7t
//int [] counts = ps.executeBatch();⑶ ur2!#bU9
conn.commit(); xKJ>gr"w#
}catch(Exception e){ @5}gsC
e.printStackTrace(); En9R>A;`
} finally{ %3a|<6
try{ (clU$m+oXX
if(ps!=null) { [l[{6ZXt
ps.clearParameters(); "'eWn6O(
ps.close(); pX<a2FP
ps=null; S>ugRasZ$
} X_70]^XL
}catch(SQLException e){} mPmB6q%)]
DBUtils.closeConnection(conn); R.7#zhC`4
} a%~yol0wO7
} \OHv|8!EI@
public long getLast(){ $+:(f{Va*
return lastExecuteTime; =%h~/,
} nN ~GP"}
public void run(){ #Mi|IwL
long now = System.currentTimeMillis(); ^&:'NR
if ((now - lastExecuteTime) > executeSep) { }#b
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//System.out.print("lastExecuteTime:"+lastExecuteTime); b4~H3|
//System.out.print(" now:"+now+"\n"); H,>#|F
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 'H=weH
lastExecuteTime=now; Gm&2R4 )EP
executeUpdate(); !.+"4TF
} J`Oy .Qu)
else{ cztS]dcf>~
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 6f}e+ 80
} |R'i:=
} ]M4NpUM
} Tj,2r]g`<
//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 v'nHFC+p
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类写好了,下面是在JSP中如下调用。 iUNnPJh
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<% PqhlXqX9
CountBean cb=new CountBean(); VBx,iuaw
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); s -Y +x
CountCache.add(cb); A!;meVUs
out.print(CountCache.list.size()+"<br>"); MCAXt1sL&E
CountControl c=new CountControl(); Wg1tip8s
c.run(); ${e&A^h
out.print(CountCache.list.size()+"<br>"); q$^<zY
%>