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: AI^AK0.L
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CountBean.java
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/* _9Dn\=g
* CountData.java .x)>f
*
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* Created on 2007年1月1日, 下午4:44 &K9VEMCEX
* ".~MmF
* To change this template, choose Tools | Options and locate the template under 5z9r S<
* the Source Creation and Management node. Right-click the template and choose T!m42EvIvE
* Open. You can then make changes to the template in the Source Editor. '`M#UuU
*/ jHkyF`<+
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package com.tot.count; 9l]UE0yTL/
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/** i>ESEmb-
* >VRo|o<D
* @author g)=V#Bglv
*/ 4'+d"Ok
public class CountBean { T4V[RN
private String countType; 96.IuwL*.s
int countId; SjZd0H0
/** Creates a new instance of CountData */ 3gxf~$)?
public CountBean() {} U-Af7qO
public void setCountType(String countTypes){ #t"9TP
this.countType=countTypes; vqrBRlZ
} M*g2VyZ
public void setCountId(int countIds){ $x;tSJ)m~
this.countId=countIds; Nf=C?`L
} )x$!K[=
public String getCountType(){ ,3w I~j=
return countType; #rhVzN-?)W
} 2LCc
public int getCountId(){ &M0o&C-1/
return countId; pd=7^"[};
} N; rXl8
} b*lKT]D,
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CountCache.java c_~XL^B@
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/* ::4"wU3t
* CountCache.java pWMiCXnW
* MB}:GY?
* Created on 2007年1月1日, 下午5:01 -6uH.
* 1t0bUf;(M
* To change this template, choose Tools | Options and locate the template under i{<8
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* the Source Creation and Management node. Right-click the template and choose ! a86iHU
* Open. You can then make changes to the template in the Source Editor. =L:[cIRrT;
*/ <2n'}&F
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package com.tot.count; I'x$,s
import java.util.*; Q<z)q<e
/** *
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* \z2vV+f
* @author MNkKy(Za
*/ '"Bex`
public class CountCache { V%i<;C
public static LinkedList list=new LinkedList(); Zkw J.SuU
/** Creates a new instance of CountCache */ PqTYAN&F
public CountCache() {} b OW}"
public static void add(CountBean cb){ uEBQoP2
if(cb!=null){ YavfjS:2
list.add(cb); ri_P;#lz
} 8&i;hZm
} gs$3)t
} _Mlhumt
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CountControl.java jeY4yM
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/* RwUW;hU
* CountThread.java Vz%"9`r
* S*;#'j)4+
* Created on 2007年1月1日, 下午4:57 ERk kSTp
* J =b*
* To change this template, choose Tools | Options and locate the template under rU],J!LF
* the Source Creation and Management node. Right-click the template and choose CP}0Ri)
* Open. You can then make changes to the template in the Source Editor. )m|C8[ u
*/ A3xbT\xdg
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package com.tot.count; bSQ_"
import tot.db.DBUtils; X )I/%{
import java.sql.*; 3QH(4N
/** 3 Q@9S
* n1_ %Td
* @author @v"T~6M
*/ H1Q''$}Z.
public class CountControl{ Mk<m6E$L
private static long lastExecuteTime=0;//上次更新时间 IT,"8s
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 QDP-E[
/** Creates a new instance of CountThread */ SzRL}}I
public CountControl() {} 2%bhW,?I
public synchronized void executeUpdate(){ :g&>D#{
Connection conn=null; GX7VlI[
PreparedStatement ps=null; m{VL\ g)
try{ SF0Jb"kS
conn = DBUtils.getConnection(); m^z,,t9
conn.setAutoCommit(false); /;+oz
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 5Lw{0uLr
for(int i=0;i<CountCache.list.size();i++){ 2ed@HJu
CountBean cb=(CountBean)CountCache.list.getFirst(); d"Bo8`_
CountCache.list.removeFirst(); .Xi2G@D
ps.setInt(1, cb.getCountId()); T)`gm{T
ps.executeUpdate();⑴ #uB[&GG}W
//ps.addBatch();⑵ Yi[4DfA
} .a {QA
//int [] counts = ps.executeBatch();⑶ H%FM
conn.commit(); ^Wf
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}catch(Exception e){ g/x_m.
e.printStackTrace(); B.El a
} finally{ FZeP<Ban
try{ U8E0~[y'
if(ps!=null) { *jGPGnSo
ps.clearParameters(); (yfXMp,x
ps.close(); ]XY0c6
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ps=null; fa"\=V2S
} ZH% we
}catch(SQLException e){} v< Ty|(gd
DBUtils.closeConnection(conn); K@HLIuz4t
} W.IH#`-9E
} cFw3Iw"JJ
public long getLast(){ B+|IZoR
return lastExecuteTime; 2f `&WUe
} -W9gH
public void run(){ 9g96 d-
long now = System.currentTimeMillis(); ci;&CHa
if ((now - lastExecuteTime) > executeSep) { -7&?@M,u
//System.out.print("lastExecuteTime:"+lastExecuteTime); j+nv=p
//System.out.print(" now:"+now+"\n"); (p^S~Ax
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); FbmsN)mv!%
lastExecuteTime=now; u9BjgK(M
executeUpdate(); f0OgK<.>T
} 'w:bs!
else{ CNq[4T'~A
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); f7ZA837Un
} R#D#{cC(
} Y!F!@`%G
} 'bl%Y).9w
//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 lz-
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类写好了,下面是在JSP中如下调用。 2g0K76=Co:
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<% <vL}l: r
CountBean cb=new CountBean(); f*v1J<1#
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ve6x/ PD
CountCache.add(cb); =Aj"j-r&{
out.print(CountCache.list.size()+"<br>"); p x0Sy|
CountControl c=new CountControl(); Nvhy3
c.run(); =88t*dH(,"
out.print(CountCache.list.size()+"<br>"); 3Mur*tj#
%>