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: +~Cy$MCX
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CountBean.java ^W83ByP
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/* TTNkr`
* CountData.java !v#xb3"/
* fg%&N2/(.B
* Created on 2007年1月1日, 下午4:44 VU|dV\>
* }$su4A@0
* To change this template, choose Tools | Options and locate the template under }`_@'4:t
* the Source Creation and Management node. Right-click the template and choose 0O!cN_l|
* Open. You can then make changes to the template in the Source Editor. iyx>q!P
*/ o(A|)c4k
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package com.tot.count; T0HuqJty
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/** sE(HZR1
* 8Ad606
* @author A!W0S
*/ d?idTcgs
public class CountBean { m"tOe?
private String countType; zQy"m-Q
int countId; 3ucP(Ex@tg
/** Creates a new instance of CountData */ CCijf]+
public CountBean() {} 6w3R'\9
public void setCountType(String countTypes){ pz^<\
this.countType=countTypes; XP[uF ;w
} K5Wg"^AHY/
public void setCountId(int countIds){ I lR\
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this.countId=countIds; ?gGt2O1J
} <M?:
public String getCountType(){ EER`?Sa(
return countType; M
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} wVs.Vcwr
public int getCountId(){ igf)Hb;5
return countId; Ha>*?`?yI
} gv15t'y9
} UK#&lim
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CountCache.java _Yb_D/
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/* N8cAqr
* CountCache.java 5}ie]/[|
* = iB,["s
* Created on 2007年1月1日, 下午5:01 9D\4n
* Uh}seB#mJj
* To change this template, choose Tools | Options and locate the template under d87vl13
* the Source Creation and Management node. Right-click the template and choose PrQ?PvA<L
* Open. You can then make changes to the template in the Source Editor. vEM(bT=H
*/ Zx }&c |Q
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package com.tot.count; vQV K$n`
import java.util.*; $>M<j
/** f}c\_}(
* txql 2
* @author HY;o^drd
*/ cNpe_LvW
public class CountCache { 4o:hyh
public static LinkedList list=new LinkedList(); R$kpiqK
/** Creates a new instance of CountCache */ =tTqN+4
public CountCache() {} ^(}585b
public static void add(CountBean cb){ @*N)i?>
if(cb!=null){ ]Hj<IvG
list.add(cb); 9ch#}/7B
} Z[!d*O%R_
} Ey{%XR+*;
} 1iT\df
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CountControl.java 73A)lU.
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/* {Ee>n^1
* CountThread.java B-.v0R`5
* X#a`K]!B
* Created on 2007年1月1日, 下午4:57 57{oh")
* {)f~#37
* To change this template, choose Tools | Options and locate the template under ExSe=4q#
* the Source Creation and Management node. Right-click the template and choose G}@#u9
* Open. You can then make changes to the template in the Source Editor. /(I*,.d
*/ 8qi+IGRg
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package com.tot.count; !%<^K.wG
import tot.db.DBUtils; kU5.iK'
import java.sql.*; 4Q=ftY<
/** 3Rg}+[b
* fyz
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* @author /NT[ETMk+
*/ @(``:)Z<b
public class CountControl{ 3XiO@jzre
private static long lastExecuteTime=0;//上次更新时间 =!Vf
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 g o5]<4`r
/** Creates a new instance of CountThread */ F-(dRSDNM
public CountControl() {} T`/IO.2
public synchronized void executeUpdate(){ M/D)".;
Connection conn=null; B
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PreparedStatement ps=null; kpwt]]e*
try{ hli|B+:m"
conn = DBUtils.getConnection(); Oh.ZPG=
conn.setAutoCommit(false); *x~xWg9^
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 1RLY $M
for(int i=0;i<CountCache.list.size();i++){ WlB'YL-`g
CountBean cb=(CountBean)CountCache.list.getFirst(); ;P &y,:<m:
CountCache.list.removeFirst(); ;T]d MfO
ps.setInt(1, cb.getCountId()); 5 v^yQ<70
ps.executeUpdate();⑴ $!vxVs9n
//ps.addBatch();⑵ h)lPi
} 31^cz*V
//int [] counts = ps.executeBatch();⑶ <q)4la
conn.commit(); 6Q4X6U:WB
}catch(Exception e){ IJOvnZ("A
e.printStackTrace(); rn@`yTw^
} finally{ U;_[b"SW%
try{ 4Ph0:^i_
if(ps!=null) { vP%tk s+.
ps.clearParameters(); ~jU/<~s
ps.close();
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ps=null; Mj>}zbpk/
} js^ ,(CS
}catch(SQLException e){} ~Vh(6q.oT
DBUtils.closeConnection(conn); .Hhh i
} pN6%&@) =
} W^,S6!
public long getLast(){ }*]B-\>
return lastExecuteTime; v1U?&C
} )/ Ud^wi
public void run(){ rr`;W}3
long now = System.currentTimeMillis(); d|9b~_::V
if ((now - lastExecuteTime) > executeSep) { PW(\4Q\
//System.out.print("lastExecuteTime:"+lastExecuteTime); 0oA{Jix
//System.out.print(" now:"+now+"\n"); qM4c]YIaSl
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); S|V4[ssB
lastExecuteTime=now; [./6At&|
executeUpdate(); }/dRU${!
} ubsSa}$q
else{ #BVtL :x@
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); $aCd/&
} 3H\w2V
} 3FSqd<t;D
} g3n'aD@'x
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 iq#b#PYA
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类写好了,下面是在JSP中如下调用。 dhg~$CVO
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<% BC>=B@H0
CountBean cb=new CountBean(); i=a-<A5x
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 2'jOP"G
CountCache.add(cb); #qU-j/Qf
out.print(CountCache.list.size()+"<br>"); gbOpj3
CountControl c=new CountControl(); DF]9@{
c.run(); E"iUq
out.print(CountCache.list.size()+"<br>"); SEwku}
%>