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: [|O6n"'
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CountBean.java q x }fn/:
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/* -t#a*?"$w
* CountData.java o5@P>\u>
* Y]0y
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* Created on 2007年1月1日, 下午4:44 ghR]$SG
* g' U^fN
* To change this template, choose Tools | Options and locate the template under T>o# *{qn
* the Source Creation and Management node. Right-click the template and choose W/X;|m`
* Open. You can then make changes to the template in the Source Editor. 717m.t,x
*/ ,qqV11P]
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package com.tot.count; fT~<C
{
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/** 9+|,aG s
* Io X9yGq
* @author -T6%3>h
*/ >{=RQgGy
public class CountBean { YAG3PWmD
private String countType; Z6ex<[`I
int countId; ?kefRev<#h
/** Creates a new instance of CountData */ R6.#gb8^oS
public CountBean() {} Q'M Ez
public void setCountType(String countTypes){ 3!UP>,!
this.countType=countTypes; 3goJ(XI
} _j
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public void setCountId(int countIds){ &y+*3,!n8
this.countId=countIds; yKhzymS}T
} $X]v;B)J|
public String getCountType(){ N Uml"
return countType; BJrNbo;T
} _(
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public int getCountId(){ oIgj)AY<
return countId; j"=jK^
} e-t`\5b;
} {<BK@U
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CountCache.java
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/* o`Brr:
* CountCache.java #=3]bg
* TC}u[kM
* Created on 2007年1月1日, 下午5:01 xq*yZ5:5Jo
* _/\H3
* To change this template, choose Tools | Options and locate the template under Y>~zt -
* the Source Creation and Management node. Right-click the template and choose !g:UM R
* Open. You can then make changes to the template in the Source Editor. 7!)%%K.z6
*/ :M`BVZ1t
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package com.tot.count; IGQ8-#=
import java.util.*; |th )Q
/** _xsYcw~)
* @>ZjeDG>
* @author e:R[
*/ ,"ZlY}!Gn
public class CountCache { w!M ^p&T7
public static LinkedList list=new LinkedList(); 4(IP
/** Creates a new instance of CountCache */ C" WZsF^3
public CountCache() {} (#`o>G(
public static void add(CountBean cb){ YT8`Vz$+
if(cb!=null){ gC- 0je
list.add(cb); w5\)di
} \}W.RQ^3
} fXj
} {}e IpK,+
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CountControl.java -]%@,L^@
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/* #YdU,y=B
* CountThread.java ?sE21m?b-
* gV BV@v!W
* Created on 2007年1月1日, 下午4:57 5Bk
* ;wZ.p"T9^
* To change this template, choose Tools | Options and locate the template under fOAb?:D
* the Source Creation and Management node. Right-click the template and choose ny}utO
* Open. You can then make changes to the template in the Source Editor. GK+w1%6)
*/
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package com.tot.count; G=e[TR)i
import tot.db.DBUtils; ,Nh X%
import java.sql.*; RPwSo.c4
/** k=}hY+/=
* $_kU)<e3
* @author 4+"SG@i`W
*/ LLiX%XOh
public class CountControl{ |n8^Xsx4w
private static long lastExecuteTime=0;//上次更新时间 M`'2
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private static long executeSep=60000;//定义更新间隔时间,单位毫秒 !hUyX}{`j
/** Creates a new instance of CountThread */ f5Oh#
public CountControl() {} ,fRb6s-
public synchronized void executeUpdate(){ g^FH[(P[G
Connection conn=null; 2t<CAKBB
PreparedStatement ps=null; )1le- SC
try{ C/G[B?:h
conn = DBUtils.getConnection(); "H8N,eb2
conn.setAutoCommit(false); 7dZ!GX?\y
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); Jjv&@a}
for(int i=0;i<CountCache.list.size();i++){ H#K|SSqY?
CountBean cb=(CountBean)CountCache.list.getFirst(); ,H8Pmn?
CountCache.list.removeFirst(); 7
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ps.setInt(1, cb.getCountId()); uDR(^T{g#
ps.executeUpdate();⑴ X,~C
//ps.addBatch();⑵ ~MF. M8
} _nUuiB>
//int [] counts = ps.executeBatch();⑶ ,*US) &x
conn.commit(); "^`AS"z'
}catch(Exception e){ m{|n.b
e.printStackTrace(); !v=ha%w{
} finally{ &/p9+gd
try{ l"/O s_4O
if(ps!=null) { gC.T5,tn
ps.clearParameters(); qI9 BAs1~}
ps.close(); KV2X[1
ps=null; &CgD smJo#
} NT0q!r/!
}catch(SQLException e){} 3;AAC (X
DBUtils.closeConnection(conn); e!#:h4I
} wuCODz@~
} "\
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public long getLast(){ '4EJ_Vhztc
return lastExecuteTime; $1YnQgpT
} nM#\4Q[}Jh
public void run(){ 3c)xNXq m
long now = System.currentTimeMillis(); } 2KuY\5\i
if ((now - lastExecuteTime) > executeSep) { qW*)]s)z
//System.out.print("lastExecuteTime:"+lastExecuteTime); G8VWx&RE
//System.out.print(" now:"+now+"\n"); ! WNr09`
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); \oyr[so(i
lastExecuteTime=now; Zr3KzY9
executeUpdate(); <>cajQ@
} G6FknYj
else{ DwPl,@T_i\
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); e8Jd*AKjb
} I~,*Rgv/Z
} WD<M
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} ET4YoH>
//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 3~ylBJJ
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类写好了,下面是在JSP中如下调用。 6Y=)12T
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<% HzV3O-Qz]
CountBean cb=new CountBean(); 7y!{lr=n
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); WukD|BCC
CountCache.add(cb); gU:jx
out.print(CountCache.list.size()+"<br>"); YRFM1?*
CountControl c=new CountControl(); Dcq^C LPY
c.run(); 6B=J*8
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out.print(CountCache.list.size()+"<br>"); sHNt>5p
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