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: \i
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CountBean.java IyTL|W6
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/*
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* CountData.java 2-G he3
* EdQ:8h
* Created on 2007年1月1日, 下午4:44 {d`e9^Z:
* N[$bP)h7
* To change this template, choose Tools | Options and locate the template under eow6{CD8
* the Source Creation and Management node. Right-click the template and choose u nE h
* Open. You can then make changes to the template in the Source Editor. sZ`C
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*/ oK;.|ja
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package com.tot.count; 9f
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/** Rv9oK-S
* sflH{!;p
* @author j{)_&|^{
*/ I@dS/
public class CountBean { fbF *C V
private String countType; <gU^#gsGra
int countId; plL##?<D<
/** Creates a new instance of CountData */ XA`<*QC<
public CountBean() {} ICSi<V[y1
public void setCountType(String countTypes){ sjBP#_lW
this.countType=countTypes; 8v&4eU'S
} S{cy|QD
public void setCountId(int countIds){
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this.countId=countIds; O+vuv,gNi
} n W2[x;
public String getCountType(){ IY$H M3t7
return countType; d!0p^!3
} xL,;(F\^
public int getCountId(){ v=4,kG
return countId; OhT?W[4
} CBC0X}_`
} `TNWLD@Z
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CountCache.java f?O?2g
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/* jOs&E^">&B
* CountCache.java 0)/L+P5
* o"F=3b~:n
* Created on 2007年1月1日, 下午5:01 <ptZY.8N
* 8r@_b
* To change this template, choose Tools | Options and locate the template under _~f&wkc
* the Source Creation and Management node. Right-click the template and choose Gni<@;}
* Open. You can then make changes to the template in the Source Editor. ` <+MR6M
*/ d_CY=DHF%`
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package com.tot.count; OZ2gIK
import java.util.*; ,k}-I65M*t
/** s)HLFdis@
* p<#WueR[
* @author OQt_nb#z`{
*/ \XaKq8uE
public class CountCache { m44Ab6gpsb
public static LinkedList list=new LinkedList(); ~>:uMXyV2t
/** Creates a new instance of CountCache */ ^8p=g-U\
public CountCache() {} Y%AVC9(
public static void add(CountBean cb){ <d".v
if(cb!=null){ wO6
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list.add(cb); tOx)t$ix
} eH.~c3o
} _tJp@\rOz=
} Ke0j8|
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CountControl.java .W[ 9G\
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/* '1|FqQ\.
* CountThread.java X
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* iYwzdW1
* Created on 2007年1月1日, 下午4:57 E1 )7gio
* B}n
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* To change this template, choose Tools | Options and locate the template under 6_`9
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* the Source Creation and Management node. Right-click the template and choose ] B
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* Open. You can then make changes to the template in the Source Editor. 9?8Yf(MC%u
*/ M^f+R'Q3
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package com.tot.count; hfUN~89;
import tot.db.DBUtils; Yyl(<,Yi
import java.sql.*; -:mT8'.F-
/** [wHGt?R
* /G}TPXA
* @author Tf[o'=2
*/ :Fe}.* t
public class CountControl{ tGq0f"}'J
private static long lastExecuteTime=0;//上次更新时间 lOk'stLNa&
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 5,H,OZ}
/** Creates a new instance of CountThread */ yHrYSEM
public CountControl() {} Yz6+
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public synchronized void executeUpdate(){ [FhFeW>
Connection conn=null; EZICH&_
PreparedStatement ps=null; >x/;'Y.
try{ a#Yo^"*1
conn = DBUtils.getConnection(); puE!7:X7
conn.setAutoCommit(false); ",9QqgY+
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); o*\Fj}l-
for(int i=0;i<CountCache.list.size();i++){ ~yrEB:w`_
CountBean cb=(CountBean)CountCache.list.getFirst(); G)|s(C!
CountCache.list.removeFirst(); )?L
ps.setInt(1, cb.getCountId()); ~hx__^]d
ps.executeUpdate();⑴ |2ttdc.
//ps.addBatch();⑵ rV
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} ()Cw;N{E
//int [] counts = ps.executeBatch();⑶ vz{Z
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conn.commit(); S.iCkX
}catch(Exception e){ c-?2>%;(V
e.printStackTrace(); Y/|wOm;|
} finally{ $0(~ID
try{ VB(S]N)F^
if(ps!=null) { ^seb8o7
ps.clearParameters(); a,>`ab%>
ps.close(); 2|n)ZP2cp
ps=null; /*$B
} R:[IH2F s
}catch(SQLException e){} #KFpT__F
DBUtils.closeConnection(conn); T/9`VB%N
} "}91wfG9
} J.t tJOP
public long getLast(){ 948 lL&
return lastExecuteTime; # Vq"Cf
} N51g<K
public void run(){ cz{5-;$9Z
long now = System.currentTimeMillis(); Ei$@)qS/
if ((now - lastExecuteTime) > executeSep) { bOvMXj/HV=
//System.out.print("lastExecuteTime:"+lastExecuteTime); >I*Qc<X91
//System.out.print(" now:"+now+"\n"); q8Z,XfF^S
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); :<"b"{X"
lastExecuteTime=now; =W*Js %4
executeUpdate(); X{-@3tG<r
} et-<ib<lY
else{ e
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//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); i
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} z]\CI:
} 4Iq-4IG(
} QP%*`t?
//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 3Mlwq'pzD
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类写好了,下面是在JSP中如下调用。 Q+r8qnL'
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<% :t'*fHi~
CountBean cb=new CountBean(); sy
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); q|EE
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CountCache.add(cb); i^O(JC
out.print(CountCache.list.size()+"<br>"); Y*KHr`\C4
CountControl c=new CountControl(); R,
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c.run(); c!2j+ORz
out.print(CountCache.list.size()+"<br>"); fNh0?/3)
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