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: c1)BGy li
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CountBean.java $,z[XM&9)
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/* ,\m;DR1
* CountData.java [+:mt</HN
* 3;t@KuQ66
* Created on 2007年1月1日, 下午4:44 laD.or
* &8:iB {n
* To change this template, choose Tools | Options and locate the template under [`Qp;_K?t
* the Source Creation and Management node. Right-click the template and choose Gct&}]3pm
* Open. You can then make changes to the template in the Source Editor. ;*j6d3E
*/ ^Q43)H0
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package com.tot.count; 8IT_mjj
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/** @y;tk$e
* @=MZ6q
* @author oC@"^>4
*/
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public class CountBean { "x=@,*Bk
private String countType; &Gy'AUz-
int countId; kERaY9L\
/** Creates a new instance of CountData */ Rrs`h `'-
public CountBean() {} r=P$iG'&
public void setCountType(String countTypes){ 9`gGsC
this.countType=countTypes; om*tdG
} $Kw"5cm
public void setCountId(int countIds){ tx|"v|&e2
this.countId=countIds; mAYr<=
} X"qbB4(I
public String getCountType(){ !5'
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return countType; I")"s
} gqHH Hh
public int getCountId(){ &]"_pc/>m
return countId; Bgo"JNM
} 79c 9+
} <'4!G"_EP
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CountCache.java ?:;hTY
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/* pRk'GR]`
* CountCache.java r/s&ee
* |V~(mS747:
* Created on 2007年1月1日, 下午5:01 7,&]1+n
* Lct+cKKU
* To change this template, choose Tools | Options and locate the template under 6_`eTL=G
* the Source Creation and Management node. Right-click the template and choose \.{pZMM
* Open. You can then make changes to the template in the Source Editor. ?+} E
*/ 9>$%F;JP44
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package com.tot.count; w4<u@L
import java.util.*; qdkTg: QJ,
/** 6!}m$Dvt~
* ETH#IM8J
* @author ~_ l:b
*/ BGh8 \2
public class CountCache { dC;d>j,
public static LinkedList list=new LinkedList(); >`,#%MH#
/** Creates a new instance of CountCache */ EK- bvZ
public CountCache() {} pg}DC0a
public static void add(CountBean cb){ MS*Mem,
if(cb!=null){ enD C#
list.add(cb); DRBYH(
} k}Clq;G
} <4A(Z$ZX)
} gQ+_&'C
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CountControl.java BUy}Rn
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/* 5-QvQ&eH.
* CountThread.java WG[0$j
* C>K"ZJ
* Created on 2007年1月1日, 下午4:57 $Ln2O#
* Z5^,!6
* To change this template, choose Tools | Options and locate the template under lj}1'K@M
* the Source Creation and Management node. Right-click the template and choose bM3'm$34
* Open. You can then make changes to the template in the Source Editor. 2Nt]Nj`
*/ *}WqYqOow
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package com.tot.count; K?9H.#(
import tot.db.DBUtils; aid)q&AcQ
import java.sql.*; G}hkr
/** B8#f^}8
* "F.J>QBd
* @author v'Py[[R
*/ ^MWW,`
public class CountControl{ ;uo|4?E:\(
private static long lastExecuteTime=0;//上次更新时间 $}h_EI6hS
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 Y8CYkJTAD-
/** Creates a new instance of CountThread */ O6/=/-?N=c
public CountControl() {} 8'_
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public synchronized void executeUpdate(){ VTX'f2\
Connection conn=null; PQ!?gj
PreparedStatement ps=null; B xN#Nk~
try{ ABYW1K=
conn = DBUtils.getConnection(); T6?d`i i1
conn.setAutoCommit(false);
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ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); RkXLE"G'
for(int i=0;i<CountCache.list.size();i++){ !\|@{UJk/
CountBean cb=(CountBean)CountCache.list.getFirst(); apWrcaj
CountCache.list.removeFirst(); @Oc}\Rg
ps.setInt(1, cb.getCountId()); j~j
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ps.executeUpdate();⑴ ne~#{q
//ps.addBatch();⑵ By"ul:.D
} %$-3fj7
//int [] counts = ps.executeBatch();⑶ HvfTC<+H
conn.commit(); f*H}eu3/j
}catch(Exception e){ [~r$US
e.printStackTrace(); nv|y@!(
} finally{ 6nk|*HPz
try{ JC?V].) y5
if(ps!=null) { i~PZvxt
ps.clearParameters(); g8@i_
ps.close(); BOcEL%+
ps=null; )UU6\2^
} &(U=O?r7
}catch(SQLException e){} Ita!07
DBUtils.closeConnection(conn); M(f*hOG{Y
} ha'm`LiX
} tp3N5I
public long getLast(){ ea;c\84_N
return lastExecuteTime; Tf]VcEF
} X/D9%[{&
public void run(){ HE.Dl7{
long now = System.currentTimeMillis(); p.7p,CyB
if ((now - lastExecuteTime) > executeSep) { RPqn#B
//System.out.print("lastExecuteTime:"+lastExecuteTime);
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//System.out.print(" now:"+now+"\n"); g<jK^\eW
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); -Y,Ibq
lastExecuteTime=now; 8i
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executeUpdate(); leqSS}KU+
} /|^^v DL
else{ Jx[e{o)o
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 46JP1
} \}&w/.T
} dufHd
} hzVr3;3Zn
//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 VTkT4C@I;Y
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类写好了,下面是在JSP中如下调用。 BP><G^
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<% TgG)btQ
CountBean cb=new CountBean(); ^O9m11
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ep1Ajz.l
CountCache.add(cb); g(/O)G.
out.print(CountCache.list.size()+"<br>"); Z19y5?uR
CountControl c=new CountControl();
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c.run(); Tfs9<k>G#
out.print(CountCache.list.size()+"<br>"); j[
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