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: P~^VLnw
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CountBean.java aJ3.D
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/* ~C31=\$
* CountData.java |1/UC"f
* ;%`oS.69
* Created on 2007年1月1日, 下午4:44 ;_dOYG1
* TO5#iiM)
* To change this template, choose Tools | Options and locate the template under (`cXS5R
* the Source Creation and Management node. Right-click the template and choose PO@b9O
* Open. You can then make changes to the template in the Source Editor. J`d_=C?J
*/ ah2L8jN"
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package com.tot.count; 3vC"Q!J&
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/** /73ANQ"
* C
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* @author hYSzr-)
*/ m3']/}xHO
public class CountBean { ?K!^[aO}=
private String countType; |?\J,h
int countId; aUYq~E tj
/** Creates a new instance of CountData */ '?O_(%3F0
public CountBean() {} AA &>6JB{
public void setCountType(String countTypes){ |)[I$]L
this.countType=countTypes; S(ky:
} I ]HP
public void setCountId(int countIds){ */)O8`}2
this.countId=countIds; T)lkT?
} 4Je[!X@C
public String getCountType(){ 8_=MP[(H
return countType; 4T??8J-J
} LM2S%._cj;
public int getCountId(){ `P
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return countId; N/x]-$fl
} Em]2K:
} 5D6 ,B
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CountCache.java _)XZ;Q
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/* `)TuZP_)
* CountCache.java J>dIEW%u
* EGw;IFj)
* Created on 2007年1月1日, 下午5:01 vT{+Z\LL=
* khQ@DwO*\=
* To change this template, choose Tools | Options and locate the template under h]>7Dl]
* the Source Creation and Management node. Right-click the template and choose Rc2JgV
* Open. You can then make changes to the template in the Source Editor. (TTS-(
*/ iPCDxDLN3V
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package com.tot.count; a\ZNN k
import java.util.*; c1sVdM}|
/** G/N 1[)
* E2i'lO\P
* @author :>K8oE
*/ t->I# t7
public class CountCache { :ZsAWe{%,J
public static LinkedList list=new LinkedList(); sL4j@Lt
/** Creates a new instance of CountCache */ xRbtiFk9H
public CountCache() {} yN{TcX
public static void add(CountBean cb){ Csf!I@}Z
if(cb!=null){ _~.S~;o!b
list.add(cb); ]Ei*I}
} z2U^z*n{
} MRN=-|fV^
} :-tMH02c
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CountControl.java 3,^.
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/* KXT9Wt=
* CountThread.java -LU%z'
* bc]SY =
* Created on 2007年1月1日, 下午4:57 fJD+GvV$x
* ?)O!(=6%'
* To change this template, choose Tools | Options and locate the template under PrhGp
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* the Source Creation and Management node. Right-click the template and choose _^@ >I8ix
* Open. You can then make changes to the template in the Source Editor. ["WWaCcx
*/ U28frRa
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package com.tot.count; T!X`"rI
import tot.db.DBUtils; +!cibTQTT
import java.sql.*; k"F \4M
/** 2#Du5d
* NCivh&HR
* @author dZ|x `bIgs
*/ $&X-ay o
public class CountControl{ qGdoRrp0Ov
private static long lastExecuteTime=0;//上次更新时间 $ww0$
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 8k )i-&R
/** Creates a new instance of CountThread */ +'9E4Lpx
public CountControl() {} agd^ga3
public synchronized void executeUpdate(){ D9JHx+Xf>
Connection conn=null; UIC~%?oIA
PreparedStatement ps=null; yrG=2{I
try{ S*V!t=
conn = DBUtils.getConnection(); q,T4-
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conn.setAutoCommit(false); DCKH^J
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); M
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for(int i=0;i<CountCache.list.size();i++){ o&MOcy D
CountBean cb=(CountBean)CountCache.list.getFirst(); opgNt o6$
CountCache.list.removeFirst(); @tlWyUju
ps.setInt(1, cb.getCountId()); qFXx/FZ
ps.executeUpdate();⑴ 8EY]<#PN
//ps.addBatch();⑵ ihd^P]
} UsgrI>|l
//int [] counts = ps.executeBatch();⑶ TjS&V
conn.commit(); G=PX'dS
}catch(Exception e){ .`jYrW-k
e.printStackTrace(); (*Z:ByA
} finally{ n;LjKE
try{ a FL;E
if(ps!=null) { H,EGB8E2
ps.clearParameters(); PZihC
ps.close(); F^CR$L& K
ps=null; t!\B6!Fo
} &3 *#h
}catch(SQLException e){} k
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DBUtils.closeConnection(conn); /vs79^&
} Ch_eK^ g1
} RMHJI6?LB
public long getLast(){ e2kW,JV/<$
return lastExecuteTime; }H:wgy`
} LZDJ\"a-
public void run(){ INY?@in
long now = System.currentTimeMillis(); rE%HNPO
if ((now - lastExecuteTime) > executeSep) { h_5CWQSi
//System.out.print("lastExecuteTime:"+lastExecuteTime); O!P7Wu
//System.out.print(" now:"+now+"\n"); q!{>Nlk
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); nh+Hwj#(x
lastExecuteTime=now; oSLm?Lu
executeUpdate(); uyvjo)T
} o(yyj'=(
else{ Id=V\'$o
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 0ax;Q[z2
} ?\$6"c<G
} 6w~Cyu4Ov
} 1E=E ?$9sg
//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 x(A8FtG
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类写好了,下面是在JSP中如下调用。 x/ix%!8J
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<% wz>[CXpi_
CountBean cb=new CountBean(); #^{%jlmHxJ
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); /[A#iTe
CountCache.add(cb); K[S)e!\.
out.print(CountCache.list.size()+"<br>"); &WZ&Tt/)/
CountControl c=new CountControl(); z"-oD*ICw
c.run(); PYTwyqS
out.print(CountCache.list.size()+"<br>"); ;;+h4O )
%>