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: _}VloiY
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CountBean.java |{ PI102
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/* 2hQ>:
* CountData.java B0!"A
* jDN ]3Y`
* Created on 2007年1月1日, 下午4:44 `z )N,fF
* 1YJC{bO
* To change this template, choose Tools | Options and locate the template under FH%GIi
* the Source Creation and Management node. Right-click the template and choose !o+_T?
* Open. You can then make changes to the template in the Source Editor. ]mXLg:3B
*/ |7pR)KH3
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package com.tot.count; ]&{ ci
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/** Kmv+1T0,
* 9Xo[(h)5d
* @author zC:wNz@zK
*/ ^e>Wo7r
public class CountBean { 4bEf
private String countType; Z)xaJGbw
int countId;
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/** Creates a new instance of CountData */ >ap1"n9k
public CountBean() {} J@ktyd(P
public void setCountType(String countTypes){ Ze3X$%kWi
this.countType=countTypes; 8Bq!4uq\5|
} .rJiyED?!
public void setCountId(int countIds){ MqA`yvQm
this.countId=countIds; &0 BdUU+:<
} y&= ALx@
public String getCountType(){ (V% `k'N7f
return countType; FSbHn{@
} NwR}yb6
public int getCountId(){ Z@%HvB7
return countId; ;kJA'|GX
} i^!ez5z
} b(I2m
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CountCache.java 2kUxD8BcN
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/* AkT<2H|4
* CountCache.java A
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* rzI|?QaPi
* Created on 2007年1月1日, 下午5:01 5rV((
* = }:)y0L
* To change this template, choose Tools | Options and locate the template under e<#DdpX!H~
* the Source Creation and Management node. Right-click the template and choose nbTVU+
* Open. You can then make changes to the template in the Source Editor. h}Wdh1.M3
*/ 1uk0d`JL
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package com.tot.count; ?}Lg)EFH
import java.util.*; `3'0I /d"z
/** ~b|`'kU
* 1I}b|6
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* @author $CE[MZ&S
*/ C}*cx$.
public class CountCache { ^Mk%z9
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public static LinkedList list=new LinkedList(); %D`,k*X
/** Creates a new instance of CountCache */ \rV
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public CountCache() {} D*Q.G8(
public static void add(CountBean cb){ ')$NfarQ.
if(cb!=null){ lw(e3j
list.add(cb); U70]!EaT
} F("#^$
} [|3>MZ2/
} 56Z\-=KAU
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CountControl.java GBC*>Y
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/* Q9`QL3LQD
* CountThread.java a%Jx
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* 35*\_9/#
* Created on 2007年1月1日, 下午4:57 LN_OD5gZ
* tB'V
* To change this template, choose Tools | Options and locate the template under VNtPKtx\
* the Source Creation and Management node. Right-click the template and choose ,[nm_^R*\
* Open. You can then make changes to the template in the Source Editor. T^}
*/ RP`2)/sMT
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package com.tot.count; jUqy8q&
import tot.db.DBUtils; ?QDWuPhN
import java.sql.*; M'1!<a-Mp
/** j,2l8?
* da$BUAqU
* @author t=#Pya
*/ 3v!~ cC~cI
public class CountControl{ VRW]a
private static long lastExecuteTime=0;//上次更新时间 AP\ofLmq
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 v1.q$ f^(
/** Creates a new instance of CountThread */ vG2b:[W
public CountControl() {} <39!G7ny
public synchronized void executeUpdate(){ lKEa)KF[
Connection conn=null; (HN4g;{
PreparedStatement ps=null; k,Zm GllQ]
try{ bO/*2oau
conn = DBUtils.getConnection(); })IO#,
conn.setAutoCommit(false); W:QwHZ2O
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); C+MSVc
for(int i=0;i<CountCache.list.size();i++){ p&K\]l}
CountBean cb=(CountBean)CountCache.list.getFirst(); /MOnNnV
CountCache.list.removeFirst(); mi2o1"Jd$`
ps.setInt(1, cb.getCountId()); 7nHTlI1b
ps.executeUpdate();⑴ ^Dx#7bsDZR
//ps.addBatch();⑵ ]wuy_+$
}
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//int [] counts = ps.executeBatch();⑶ `$z)$VuP
conn.commit(); WO,xMfK
}catch(Exception e){ [ev-^[
e.printStackTrace(); u>Ki$xP1
} finally{ ZZ)G5ji
try{ 9|S` ub'
if(ps!=null) { "L2 m-e6
ps.clearParameters(); ;' e@t8i6
ps.close(); } IlP:
ps=null; g3?U#7i
} #cwCocw
}catch(SQLException e){} Nl8 gK{
DBUtils.closeConnection(conn); q?~Rnv
} ZcryAm:I
} /axTh
public long getLast(){ QlW=_Ymv{
return lastExecuteTime; <kD#SV%"
} y?N Nz0
public void run(){ p#_[
long now = System.currentTimeMillis(); `!w^0kZ
if ((now - lastExecuteTime) > executeSep) { 8t.dPy<
//System.out.print("lastExecuteTime:"+lastExecuteTime); CM~MoV[k7e
//System.out.print(" now:"+now+"\n"); LI:Tc7t
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ur2!#bU9
lastExecuteTime=now; e4qj .b
executeUpdate(); a`Z{
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} -rDz~M+
else{ |tG+iF@4
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); T 0 FZ7
} 9[|4[3K
} N5q725zJ
} ;WI]vn
//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 IF?xnu
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类写好了,下面是在JSP中如下调用。 {:Vf0Mhb
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<% 6d{j0?mM
CountBean cb=new CountBean(); XS0V:<+,
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); {~GR8
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CountCache.add(cb); WaYO1*=
out.print(CountCache.list.size()+"<br>"); FWTx&Ip
CountControl c=new CountControl(); MtG_9-
c.run(); |ft:|/^F&
out.print(CountCache.list.size()+"<br>"); 2;N@aZX
%>