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: _@_EQ!=
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CountBean.java vnlHUQLO
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/* ow'CwOj$
* CountData.java '_91(~P
* b<E78B+Aax
* Created on 2007年1月1日, 下午4:44 u})8)
* |2jA4C2L}
* To change this template, choose Tools | Options and locate the template under nHLMF7\
* the Source Creation and Management node. Right-click the template and choose xd4~[n\hm
* Open. You can then make changes to the template in the Source Editor. P_.AqEH
*/ emT/H95|,
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package com.tot.count; }YU\}T-P
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/** fM(~>(q&
* "|E'E"_1
* @author @F|pKf:M+
*/ {!1RlW
public class CountBean { ''p<C)Q
private String countType; 2=VFUR 8
int countId; Fc^!="H
/** Creates a new instance of CountData */ (L W2S;-
public CountBean() {} 4S* X=1
public void setCountType(String countTypes){ ~L_1&q^4!i
this.countType=countTypes; @"aqnj>+
} ( De>k8
public void setCountId(int countIds){ PJ<9T3Fa
this.countId=countIds; Y/L*0M.<
} c?Mbyay
public String getCountType(){ bUuQ"!>ppu
return countType; Jpn= ^f[rm
} ?YF2Uc8z%2
public int getCountId(){ zu,Yuq
return countId; Y3H5}4QD
} \
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} 34J*<B[Njo
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CountCache.java UC.kI&A
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/* -'^:+FU
* CountCache.java KppYe9?
* *rYPjk6g[
* Created on 2007年1月1日, 下午5:01 /^WOrMR
* 5eM{>qr}
* To change this template, choose Tools | Options and locate the template under nL]eGC
* the Source Creation and Management node. Right-click the template and choose 6$H`wDh#(&
* Open. You can then make changes to the template in the Source Editor. ~1nKL0C6u
*/ FyNm1QNy^
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package com.tot.count; w,OPM}) il
import java.util.*; 1'1>B
/** #@E:|^$1y
* FRsp?i
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* @author 6A ptq
*/ #wsi><7
public class CountCache { mA^3?yj
public static LinkedList list=new LinkedList(); D/wJF[_
/** Creates a new instance of CountCache */ y=AF
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public CountCache() {} Th$xk9TK^@
public static void add(CountBean cb){ .S]*A b
if(cb!=null){ vTC{
list.add(cb); 4,BJK`{
} 6;(b-Dhi
} #JN4K>_4
} t~":'le`zr
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CountControl.java p ^9o*k`u
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/* Ydyz-
* CountThread.java $v5 >6+-n
* ~JP3C5q
* Created on 2007年1月1日, 下午4:57 *]!rT&E
* {4)d
* To change this template, choose Tools | Options and locate the template under 9ZuKED
* the Source Creation and Management node. Right-click the template and choose !=u=P9I
* Open. You can then make changes to the template in the Source Editor. R^"mGe\LL
*/ $Z8riVJ7j-
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package com.tot.count; Emw]`
import tot.db.DBUtils; v4Kf{9q#
import java.sql.*; ]2A2<Q_,
/** ?6h~P:n.
* 3Z7gPU!H=
* @author >4os%T
*/ ,V{Bpr
public class CountControl{ -C* 6>$A
private static long lastExecuteTime=0;//上次更新时间 uavyms^
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 {`(MK6D8 c
/** Creates a new instance of CountThread */ s|X_:3\x
public CountControl() {} ant2];0p
public synchronized void executeUpdate(){ #c~-8=
Connection conn=null; R83PHM
PreparedStatement ps=null; ";DozPU
try{ K>n@8<7
conn = DBUtils.getConnection(); &kT!GU^n
conn.setAutoCommit(false); f+\ UVq?
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?");
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for(int i=0;i<CountCache.list.size();i++){ lwIxn1n
CountBean cb=(CountBean)CountCache.list.getFirst(); G2b"R{i/,
CountCache.list.removeFirst(); Bm<tCN-4
ps.setInt(1, cb.getCountId()); !/X>k{
ps.executeUpdate();⑴ \S{ihS@J
//ps.addBatch();⑵ at1oxmy
} uuL(BUGt-
//int [] counts = ps.executeBatch();⑶ +RnWeBXAT
conn.commit(); XJk~bgO*
}catch(Exception e){ <;cch6Z
e.printStackTrace(); ,$RXN8x1
} finally{ q Ll4t/p
try{ 3sDyB-\&
if(ps!=null) { C'S_M@I=
ps.clearParameters(); AoK;6je`K^
ps.close(); P,rLyx
ps=null; MM( ,D&
Z
} G&4D0f
}catch(SQLException e){} 5xU}}[|~-
DBUtils.closeConnection(conn); wNUcL*n
} d@zxgn7o
} Yu9VtC1
public long getLast(){ qOa*JA`
return lastExecuteTime; a>+m_]*JZ
} 'pF$6n;
public void run(){ w4zp%`?D'
long now = System.currentTimeMillis(); L=P8; Gj)
if ((now - lastExecuteTime) > executeSep) { 'R99m?"
//System.out.print("lastExecuteTime:"+lastExecuteTime); %/ :&L+q
//System.out.print(" now:"+now+"\n"); Ds{bYK_y
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ?v'CuWS
lastExecuteTime=now; 735l&(3A\
executeUpdate(); %4BQY>O)@
} 3Q2NiYg3
else{ @moaa} 1
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); Ak$9\Sl
} 4ywtE}mp
} dP#7ev]'
} K<WowU
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释
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类写好了,下面是在JSP中如下调用。 9NZq
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$_e{Zv[
<% ]/AU_&
CountBean cb=new CountBean(); ?}EWfsA
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); S&;)F|-q
CountCache.add(cb); X7gB.=\X
out.print(CountCache.list.size()+"<br>"); Yk*_u}?#
CountControl c=new CountControl(); ::3[H$
c.run(); +aqQa~}r
out.print(CountCache.list.size()+"<br>"); ?zVcP=p@
%>