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: >]C<j4
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CountBean.java w0\4Wa
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/* Hq79/wKj
* CountData.java QZ:v
* ;7)OSGR
* Created on 2007年1月1日, 下午4:44 AV9:O{
* P)4x
* To change this template, choose Tools | Options and locate the template under 89ZDOji?O
* the Source Creation and Management node. Right-click the template and choose i"KL;t[1
* Open. You can then make changes to the template in the Source Editor. AwA1&mh
*/ )m)h/_
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package com.tot.count; W3aXW,P. V
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/** Kl!DKeF
* w# xncH:1
* @author rg"TJ"Q-
*/ J~fuW?a]r
public class CountBean { 5=Zp%[#
private String countType; L>i<dD{
int countId; 0>8ZN!@K
/** Creates a new instance of CountData */ :R{x]sv
public CountBean() {} u;QH8LK
public void setCountType(String countTypes){ 4$qNcMdz
this.countType=countTypes; [Aa[&RX+9
} +q$xw}+PK
public void setCountId(int countIds){ _Eszr(zJ
this.countId=countIds; j#4+-
} ,K`E&hS
public String getCountType(){ <tGI]@Nwk
return countType; #IbS
} Ixyvn#ux)
public int getCountId(){ Bd/}
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return countId; N,h1$)\B#
} ?hP<@L6K
} \IO$+Guh
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CountCache.java 5F% h>tqh
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/* ^n6)YX
* CountCache.java d%S=$}o
* [BJ$|[11
* Created on 2007年1月1日, 下午5:01 rDK;6H:u{
* $:T<IU[E
* To change this template, choose Tools | Options and locate the template under *vRNG 3D/
* the Source Creation and Management node. Right-click the template and choose dxk;@Tz
* Open. You can then make changes to the template in the Source Editor. "
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*/ _K*\}un2
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package com.tot.count; )w^GPlh
import java.util.*; NKupOJJq
/** dcV,_
* {d&X/tT
* @author )er?*^9Z
*/ hP ,b-R9\
public class CountCache { jsK|D{m?
public static LinkedList list=new LinkedList(); c,+L +
/** Creates a new instance of CountCache */ 6~:W(E}
public CountCache() {} z"
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public static void add(CountBean cb){ %AzPAWcN
if(cb!=null){ PU,6h}
list.add(cb); V[BY/<z)A
} GlXA-p<
} x*5 Ch~<k
} D!l [3
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CountControl.java e|2vb
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/* !D.= 'V
* CountThread.java i}v}K'`
* $.suu^>^w
* Created on 2007年1月1日, 下午4:57 )nf=eU4|
* [
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* To change this template, choose Tools | Options and locate the template under aYv'H
* the Source Creation and Management node. Right-click the template and choose UE}8Rkt
* Open. You can then make changes to the template in the Source Editor. Jdk3)
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*/ bIvJs9L
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package com.tot.count; yv6Zo0s<J
import tot.db.DBUtils; mq|A8>g
import java.sql.*; BK`Q)[
/** 0~PXa(!^K
* I?^Q084
* @author 3D 4]yR5
*/ _WRR
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public class CountControl{ 4Zv.[V]iOO
private static long lastExecuteTime=0;//上次更新时间 kxr6sO~
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 =8$(i[;6w
/** Creates a new instance of CountThread */ gQ[]
public CountControl() {} 97:t29N
public synchronized void executeUpdate(){ 35]j;8N:
Connection conn=null; X]3l| D
PreparedStatement ps=null; =hZ&66
try{ P;HVL flu
conn = DBUtils.getConnection(); al3BWRq'f
conn.setAutoCommit(false); +SZ%&
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); UY }9
for(int i=0;i<CountCache.list.size();i++){ X\c1q4oB[
CountBean cb=(CountBean)CountCache.list.getFirst(); PsF- 9&_
CountCache.list.removeFirst(); @1J51< x
ps.setInt(1, cb.getCountId()); z$I[kR%I{
ps.executeUpdate();⑴ N+C%Z[gt[
//ps.addBatch();⑵ YYZs#_
} EyKkjEXx_
//int [] counts = ps.executeBatch();⑶ *<|~=*Ddf
conn.commit(); ^cKv JSY
}catch(Exception e){ rC1qGzg\a
e.printStackTrace(); zezofW]a
} finally{ a `[?,W:q
try{ |2t7G9[n
if(ps!=null) { VrAXOUJw6
ps.clearParameters(); 0,"n-5Im
ps.close(); u@:=qd=\
ps=null; c1)BGy li
} OTNZ!U/)j
}catch(SQLException e){} Hz!U_?
DBUtils.closeConnection(conn); qJbhPY8Ak
} [i<$ZP
} 8a":[Q[
public long getLast(){ f2R+5`$
return lastExecuteTime; -Z/6;2Q
} c|R3,<Q]
public void run(){ `/gEKrhL-
long now = System.currentTimeMillis(); u$Pf.#
if ((now - lastExecuteTime) > executeSep) { f<s'prF
//System.out.print("lastExecuteTime:"+lastExecuteTime); iaaH9X
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//System.out.print(" now:"+now+"\n"); UL@5*uiX
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); U:pLnNp`
lastExecuteTime=now; fRv
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executeUpdate(); :)
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} YQB]t=Ha
else{ QJ(e*/
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); YfrTvKX
} 4? /ot;>2
} 0?&aV_:;X
} a\[fC=]r:
//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 mNBpb}
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类写好了,下面是在JSP中如下调用。 +lDGr/
F-reb5pt.=
<% *+,Lc1|\
CountBean cb=new CountBean(); SCI-jf3WN
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 56O<CgJF<
CountCache.add(cb); )z4kP09
out.print(CountCache.list.size()+"<br>"); !5'
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CountControl c=new CountControl(); I")"s
c.run(); @$b+~X)7
out.print(CountCache.list.size()+"<br>"); 2U+z~
%>