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: ]|@^1we
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CountBean.java + 3gp%`c4
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/* <b.D&
* CountData.java qK+5NF|
* y5r4&~04
* Created on 2007年1月1日, 下午4:44 hPh-+Hb
* VTM/hJmwJ
* To change this template, choose Tools | Options and locate the template under ~u{uZ(~
* the Source Creation and Management node. Right-click the template and choose Qrv<lE1V;
* Open. You can then make changes to the template in the Source Editor. 1 zZlC#V
*/ e.> P8C<&
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package com.tot.count; O1lNAcpeM
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/** \+etCo
* R-:2HRaA
* @author <%d>v-=B
*/ >z03{=sAN
public class CountBean { ;gkM{={`p
private String countType; [
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int countId; QZs!{sZ
/** Creates a new instance of CountData */ dG{A~Z z
public CountBean() {} :h$$J
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public void setCountType(String countTypes){ eRYK3W
this.countType=countTypes; ok[i<zl;'
} j.Hf/vi`z
public void setCountId(int countIds){ hM{bavd
this.countId=countIds; PsYpxNr
} }6#
public String getCountType(){ M+>u/fldV
return countType; Uly ue
} 3<!7>]A
public int getCountId(){ Wri<h:1
return countId; 8Wx=p#_
} x4 yR8n(
} 8r{.jFGv
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CountCache.java f?Lw)hMrA
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/* 2 nCA<&
* CountCache.java JI}'dU>*U:
* Nc`L;CP
* Created on 2007年1月1日, 下午5:01 %Zi} MPx
* UfGkTwoo=
* To change this template, choose Tools | Options and locate the template under nUO0Ce
* the Source Creation and Management node. Right-click the template and choose ]esC[r]PJ
* Open. You can then make changes to the template in the Source Editor. X8|,
*/ aOp\91
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package com.tot.count; t_^4`dW`
import java.util.*; /xhKd]Q
/** &ncvGDGi
* mt
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* @author I,tud!p`
*/ ^c|/*u
public class CountCache { @dKTx#gZ
public static LinkedList list=new LinkedList(); >7|VR:U?B
/** Creates a new instance of CountCache */ hb$Ce'}N
public CountCache() {} x:Y1P:
public static void add(CountBean cb){ R_C)
if(cb!=null){ &yg|t5o
list.add(cb); Nb\4 /;#
} &
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} gdc<ZYcM
} l#o
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CountControl.java 7#XzrT]
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/* fC`&g~yK'
* CountThread.java 0kh6@y3
* i5Ggf"![
* Created on 2007年1月1日, 下午4:57 9{l}bu/u
* G{}VPcrbC
* To change this template, choose Tools | Options and locate the template under RZLq]8pM
* the Source Creation and Management node. Right-click the template and choose P:c w|Q
* Open. You can then make changes to the template in the Source Editor. ^q5#ihM
*/ K?;DMUSY\
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package com.tot.count; +7Gwg
import tot.db.DBUtils; js(pC@<q5
import java.sql.*; t@(HF-4~=
/** U^PgG|0N
* wwqEl(
* @author 6ujWNf
*/ \fOEqe*5SM
public class CountControl{ Rq -ZL{LR7
private static long lastExecuteTime=0;//上次更新时间 j 7B!h|
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 0GwR~Z}Z
/** Creates a new instance of CountThread */ zLQx%Yg!
public CountControl() {} NEs:},)o
public synchronized void executeUpdate(){ g)-te+?6
Connection conn=null; >P(.:_^p
PreparedStatement ps=null; mpyt5#f
try{ :FF=a3/"6
conn = DBUtils.getConnection(); Wwo0%<2y
conn.setAutoCommit(false); 8ag!K*\V<
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); sOY:e/_F
for(int i=0;i<CountCache.list.size();i++){ kZ~~/?B
CountBean cb=(CountBean)CountCache.list.getFirst(); gYj'(jB
CountCache.list.removeFirst(); /
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ps.setInt(1, cb.getCountId()); P?<y%c<
ps.executeUpdate();⑴ SbZ6t$"
//ps.addBatch();⑵ f);FoVa6
} [[ZJ]^n,
//int [] counts = ps.executeBatch();⑶ )oZ dj`
conn.commit(); NK+o1
}catch(Exception e){ 6!o1XQr=Z
e.printStackTrace(); xw%0>K[
} finally{ <@}9Bid!o
try{ XW9!p.*.U
if(ps!=null) { M5B# TAybC
ps.clearParameters(); =N@t'fOr
ps.close(); ?2a $*(
ps=null; *j=%
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} Xj*Wu_
}catch(SQLException e){} U*:!W=XN
DBUtils.closeConnection(conn); YIE<pX4Q7)
} 6*?F @D2&
} 0(Ij%Wi,
public long getLast(){ i4Jc.8^9$
return lastExecuteTime;
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} B!yr!DWv
public void run(){ X]=t>
long now = System.currentTimeMillis(); <i[HbgUlO.
if ((now - lastExecuteTime) > executeSep) { d-m7}2c
//System.out.print("lastExecuteTime:"+lastExecuteTime); K,]=6Rj
//System.out.print(" now:"+now+"\n"); Ru XC(qcq
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 0V]s:S
lastExecuteTime=now; +(*DT9s+
executeUpdate(); 'yth'[
} BY*Q_Et
else{ U.TA^S]`g
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); .543N<w
} ,[Fb[#Qqb
} V]N?6\Op
} JRFtsio*
//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 "L1Zi.)
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类写好了,下面是在JSP中如下调用。 zL it
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<% OTp]Xe/
CountBean cb=new CountBean(); R4@6G&2d>
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); &R siVBA
CountCache.add(cb); V:27)]q
out.print(CountCache.list.size()+"<br>"); w*!aZ,P
CountControl c=new CountControl(); $|@ r!/W
c.run(); Mlq.?-QgIL
out.print(CountCache.list.size()+"<br>"); {U1m.30n
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