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: <.}Ua(
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CountBean.java +tIz[+u
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/* BY$[ g13
* CountData.java 9_GokU P_
* yQ'eu;+]
* Created on 2007年1月1日, 下午4:44 ;@9e\!%
* G)8ChnJa!m
* To change this template, choose Tools | Options and locate the template under vnTq6:f#M
* the Source Creation and Management node. Right-click the template and choose kQIfYtT
* Open. You can then make changes to the template in the Source Editor. Q70bEHLA
*/ .9OFryo
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package com.tot.count; 9qr UM`z$g
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/** )yrAov\z*
* q4k.f_{
* @author {c@G$
*/ @UO}W_0ZD
public class CountBean { }"n7~|
private String countType; qi&D+~Gv!
int countId; Ib6(Bp9.L
/** Creates a new instance of CountData */ d/]|657u
public CountBean() {} N 'i,>
public void setCountType(String countTypes){ -6`;},Yr
this.countType=countTypes; a8zZgIV
} nkRK+~>
public void setCountId(int countIds){ E?cZbn*>`
this.countId=countIds; lVoik*,B
} ETO$9}x[
public String getCountType(){ @(>XOj?+
return countType; c" +zgP
} #]y5zi
public int getCountId(){ w4,]2Ccn.
return countId; m6i%DE
} J(e7{aRJ9
} hg8Be6G<
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CountCache.java %'0&ElQ
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/* O,|\"b1(
* CountCache.java 3cixQzb}u
* ?mU\
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* Created on 2007年1月1日, 下午5:01 3;l "=#5
* M|8
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* To change this template, choose Tools | Options and locate the template under W Y:s
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* the Source Creation and Management node. Right-click the template and choose 6G}c1nWU
* Open. You can then make changes to the template in the Source Editor. h55>{)(E
*/ MwAJ(
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package com.tot.count; .YR8v1Cp
import java.util.*; 'I v_mig
/** 6,+nRiZ
* B |&F%P0:
* @author #tDW!Xv?
*/ Y)Tl<
public class CountCache { 5g>wV
public static LinkedList list=new LinkedList(); c`jDW S
/** Creates a new instance of CountCache */ % O%xpSYr
public CountCache() {} PS@ *qTin
public static void add(CountBean cb){ Ri @`a
if(cb!=null){ 1
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list.add(cb); k':s =IXW
} 6t7fa<
} k>5 O`Y:
} rwgsXS8W6
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CountControl.java opD-vDa h
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/* L/i(KF{
* CountThread.java ]?&FOzN5$P
* D:JS)+]
* Created on 2007年1月1日, 下午4:57 9i%9
* :1;Q(9:v
* To change this template, choose Tools | Options and locate the template under %K1")s
* the Source Creation and Management node. Right-click the template and choose bfdVED
* Open. You can then make changes to the template in the Source Editor. p/*"4-S
*/ _a5(s2wq+
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package com.tot.count; mCdgKr|n
import tot.db.DBUtils; d~Mg
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import java.sql.*; i_ QcC
/** 78]gtJ
* JJnYOau
* @author P^i.La,
*/ E\$C/}T
public class CountControl{ S_\
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private static long lastExecuteTime=0;//上次更新时间 &z@~B&O
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 nIBFk?)6
/** Creates a new instance of CountThread */ h}&b+1{X
public CountControl() {} ]tY:,Mfs
public synchronized void executeUpdate(){ KOSQQf
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Connection conn=null; ;`UecLb#
PreparedStatement ps=null; ~pz FZ7n4
try{ tsv$ r$Se
conn = DBUtils.getConnection(); Lgi[u"Du
conn.setAutoCommit(false); ]db@RbaH
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); kg>>D
for(int i=0;i<CountCache.list.size();i++){ o@k84+tn(
CountBean cb=(CountBean)CountCache.list.getFirst(); h{_*oBa
CountCache.list.removeFirst(); 0m)&YFZ[(
ps.setInt(1, cb.getCountId()); Qf@iU%G
ps.executeUpdate();⑴ f$F*3
//ps.addBatch();⑵
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} sbS~N*{E
//int [] counts = ps.executeBatch();⑶ ROdK8*jL
conn.commit(); ZnfNQl[
}catch(Exception e){ v>mn/a
e.printStackTrace(); NXU`wnVJ
} finally{ aE/D*.0NI
try{ *e/K:k
if(ps!=null) { T3 pdx~66
ps.clearParameters(); |B^G:7c
ps.close(); AGq>=avv
ps=null; 9wh2f7k
} YRcps0Dx9
}catch(SQLException e){} RU&_j*U
DBUtils.closeConnection(conn); _Qd,VE
8u
} o6L9UdT
} !')y&7a~
public long getLast(){ n]N 96oD
return lastExecuteTime; ZjVWxQ
} /:[2'_Xl
public void run(){ e@n!x}t8
long now = System.currentTimeMillis(); 'q{733o
if ((now - lastExecuteTime) > executeSep) { UVEz;<5@\
//System.out.print("lastExecuteTime:"+lastExecuteTime); J4aBPq`
//System.out.print(" now:"+now+"\n"); ^p=L\SJ
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); KQ`=t
lastExecuteTime=now; ||eAE)
executeUpdate(); M+xdHBg
} `G$1n#&
else{ BfmsMW
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); k6**u
} ;[$n=VX`
} -<f;l_(
} `<fh+*
//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 9|WV~
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类写好了,下面是在JSP中如下调用。 Ph,-sR
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<% ,)fkr]`<
CountBean cb=new CountBean(); \2kPq>hu
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ^g>1U5c
CountCache.add(cb); x\@*60o
out.print(CountCache.list.size()+"<br>"); z@VP:au
CountControl c=new CountControl(); L,]=vba'$
c.run(); N "Wqy
out.print(CountCache.list.size()+"<br>"); Hs(D/&6%
%>