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: s{NEP/QQJ
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CountBean.java fPiq
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/* sRE$*^i
* CountData.java Un]`Gd]:
* kWF4k
* Created on 2007年1月1日, 下午4:44 Hig=PG5I
* ;*:d)'A
* To change this template, choose Tools | Options and locate the template under HW|c -\tS
* the Source Creation and Management node. Right-click the template and choose !aeL*`;
* Open. You can then make changes to the template in the Source Editor. ;wbQTp2
*/ z tHGY
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package com.tot.count; :@wO'
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/** $N5VoK
* k)'hNk"x
* @author iv?'&IUfK
*/ i6kW"5t
public class CountBean { iVd*62$@$
private String countType; MnO,Cd6{%d
int countId; ^8o'\V"m^
/** Creates a new instance of CountData */ /1h`O@VA
public CountBean() {}
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public void setCountType(String countTypes){ R I:x`do
this.countType=countTypes; 6]\F_Z41
} nR6~oB{-
public void setCountId(int countIds){ .i"v([eQ
this.countId=countIds; % rdW:
} ^OI
public String getCountType(){ -fj;9('YJ
return countType; vYL{5,t {1
} @~ N:F~
public int getCountId(){ 4(R O1VWsb
return countId; a)(j68c
} +N5G4t#.
}
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CountCache.java :)c >5
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/* j^1T3 +
* CountCache.java [NFg9y;{h
* Ve2z= 6(
* Created on 2007年1月1日, 下午5:01 ,YSQog
* 'P)xY-15
* To change this template, choose Tools | Options and locate the template under lT@5=ou[
* the Source Creation and Management node. Right-click the template and choose @?aNvWeavH
* Open. You can then make changes to the template in the Source Editor. x]euNa
*/ Eof1sTpA
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package com.tot.count; kNI m90,g
import java.util.*; 7t\kof
/** V{HZ/p_Y
* .Ap[C? mV
* @author c?}C{
*/ 3! dD!'
public class CountCache { *na7/ysT<
public static LinkedList list=new LinkedList(); FMwT4]y
/** Creates a new instance of CountCache */ CHdw>/5
public CountCache() {} NRcg~Nu
public static void add(CountBean cb){ 6vX+-f
if(cb!=null){ zf$OC}|\w
list.add(cb); b]g}h
} %pc0a^iB
} F@ZG| &
} 69cOdIt^D
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CountControl.java BC(f1
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/* ,ZD!Qb
* CountThread.java YM 7P!8Gc
* U@|{RP
* Created on 2007年1月1日, 下午4:57 8hQ"rrj+
* #Q^mdv?
* To change this template, choose Tools | Options and locate the template under Cs^o- g!L
* the Source Creation and Management node. Right-click the template and choose HNY{%D
* Open. You can then make changes to the template in the Source Editor. '$
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*/ (dpBGt@
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package com.tot.count; N?kXATB
import tot.db.DBUtils; c[sC 2
import java.sql.*; b[uTt'p}
/** ZB`!@/3X
* Kw(/#C:$
* @author S? r:=GS
*/ plsf` a
public class CountControl{ l2gI2Cioa
private static long lastExecuteTime=0;//上次更新时间 L^RyJ;^c
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 `*KS`
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/** Creates a new instance of CountThread */ >6:slNM#
public CountControl() {} bLCr h(<
public synchronized void executeUpdate(){ &VR<'^>
Connection conn=null; J0@m
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PreparedStatement ps=null; +O j28vR
try{ xO/44D
conn = DBUtils.getConnection(); 5iG|C ~
conn.setAutoCommit(false); k/H<UW?Z]
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++){ ;r49H<z
CountBean cb=(CountBean)CountCache.list.getFirst(); d;D^<-[i
CountCache.list.removeFirst(); q1r\60M
ps.setInt(1, cb.getCountId()); tK g%5;v
ps.executeUpdate();⑴ xW/JItF
//ps.addBatch();⑵ 5c{=/}Y
} XwX1i!'54
//int [] counts = ps.executeBatch();⑶ "y
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conn.commit(); hYi-F.Qtq
}catch(Exception e){ Z6K9E=%)c
e.printStackTrace(); >8t(qM-~:
} finally{ O5_E"um
try{ ovm*,La)g
if(ps!=null) { |1J "r.K
ps.clearParameters(); d>@{!c-
ps.close(); m1\>v?=K
ps=null; T1n GBl\(
} 0Yfk/}5
}catch(SQLException e){} wLkHU"'
DBUtils.closeConnection(conn); m$QFtrvy
} -W! g>^.
} "
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public long getLast(){ /Klwh1E
return lastExecuteTime; p"q-sMYl
} LFen!FnM
public void run(){ 8'^eH1d'
long now = System.currentTimeMillis(); ~+l%}4RZ
if ((now - lastExecuteTime) > executeSep) { _[0Ugfz(
//System.out.print("lastExecuteTime:"+lastExecuteTime); 9nM {x?
//System.out.print(" now:"+now+"\n"); "D3JdyO_S
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); S_ nTp)
lastExecuteTime=now; !RiPr(m@y
executeUpdate(); MAJvjgd..
} Qksw+ZjY#{
else{ @VxBURZ?
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); g=i|D(".
} {[r'+=}l\S
} 7T4rx53
} i;/qJKr
//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 &+&^Hc
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类写好了,下面是在JSP中如下调用。 BOt\"N
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<% =%2 E|/
CountBean cb=new CountBean(); [jAhw>
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); cv#H
CountCache.add(cb); <6v7_
out.print(CountCache.list.size()+"<br>"); g](m& O
CountControl c=new CountControl(); '\_ic=&u
c.run(); 2"BlV*\lS
out.print(CountCache.list.size()+"<br>");
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%>