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: ySwYV
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CountBean.java $N}/1R^?r
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/* 0^GbpSW{
* CountData.java mVv\bl?<
* J+)'-OFt0
* Created on 2007年1月1日, 下午4:44 MvFM,
* J$#h(D%
* To change this template, choose Tools | Options and locate the template under &jV9*
* the Source Creation and Management node. Right-click the template and choose a>wfhmr
* Open. You can then make changes to the template in the Source Editor. ]UX`=+{
*/ 5q|+p?C
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package com.tot.count; c Ndw9?Z
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/** j>0<#SYBu
* ?w+ QbT
* @author QP6z?j.
*/ DR
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public class CountBean { -A/ds1=;
private String countType; K<@[_W+
int countId; zVM4BT(
/** Creates a new instance of CountData */ le7
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public CountBean() {}
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public void setCountType(String countTypes){ Sao>P[#x
this.countType=countTypes; *:=];1O
} UGhW0X3k
public void setCountId(int countIds){ (;;J,*NP
this.countId=countIds; pOqGAD{D$
} LXHwX*`Y
public String getCountType(){ 7"ylN"syZ
return countType; jW-;4e*H=V
} AIuMX4nb
public int getCountId(){ -"W )|oC_
return countId; 5cD
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} h [nH<m
} n?'d|h
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CountCache.java <,jAk4
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/* cCM
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* CountCache.java UdT&cG
* / Zo~1q
* Created on 2007年1月1日, 下午5:01 P3'2IzNw
* W8f`J2^"M
* To change this template, choose Tools | Options and locate the template under BJ~ivT<
* the Source Creation and Management node. Right-click the template and choose {5T0RL{\N
* Open. You can then make changes to the template in the Source Editor. 9*#$0Y=
*/ G1}~.%J
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package com.tot.count; w[
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import java.util.*; ,LhEshf
/** 8@E8!w&~
* TE3*ktB{N
* @author (# JMB)
*/ rmOQ{2}
public class CountCache { h^}_YaT\
public static LinkedList list=new LinkedList(); BjM+0[HC
/** Creates a new instance of CountCache */ }o-|8P:Y
public CountCache() {} xT W3UY
public static void add(CountBean cb){ N<9w{zIK(
if(cb!=null){ "Dyym<J
list.add(cb); d
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} Tdg6kkJ
} b.QpHrnhtK
} vFTXTbt'h
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CountControl.java i-`,/e~XT
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/* brb[})}
* CountThread.java g^1r0.Sp{8
* j5kA^MTG
* Created on 2007年1月1日, 下午4:57 YU&4yk lE
* Ig<}dM.Z[
* To change this template, choose Tools | Options and locate the template under '<TD6jBs
* the Source Creation and Management node. Right-click the template and choose Q~phGD3!~
* Open. You can then make changes to the template in the Source Editor. ]bIt@GB
*/ brntE:
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package com.tot.count; gW kjUz)
import tot.db.DBUtils; l{8CISO*
import java.sql.*; SaCx)8ul0
/** bZiyapM
* +4Q[N;[+*
* @author qYx!jA]O
*/ B$ui:R/ t
public class CountControl{ pjACFVMFX
private static long lastExecuteTime=0;//上次更新时间 zt?h^zf}
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 0A.PD rM:
/** Creates a new instance of CountThread */ 2xDQ:=ec
public CountControl() {} J==}QEhQ{
public synchronized void executeUpdate(){ ?FN9rhAC
Connection conn=null; Yt{ji
PreparedStatement ps=null; ~P/]:=
try{ Vn'?3Eb<
conn = DBUtils.getConnection(); Vc| NL^
conn.setAutoCommit(false); *%X.ym'
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); =c&62;O
for(int i=0;i<CountCache.list.size();i++){ ^uhxURF
CountBean cb=(CountBean)CountCache.list.getFirst(); S/VA~,KCe;
CountCache.list.removeFirst(); ZW>o5x__b
ps.setInt(1, cb.getCountId()); 4Q;<Q"
ps.executeUpdate();⑴ NEMEY7De2
//ps.addBatch();⑵ \7yJ\I
} M+0x;53nz
//int [] counts = ps.executeBatch();⑶ wazP,9W?
conn.commit(); Wm(:P
}catch(Exception e){ 6+iK!&+=
e.printStackTrace(); Xtkw Z3
} finally{ 8)pB_en3sO
try{ (k8Z=/N~
if(ps!=null) { fWj@e"G
ps.clearParameters(); X@!X6j
ps.close(); G]-%AO{K
ps=null; 7%4.b7Q
} 45)D+
}catch(SQLException e){} };rm3;~ eg
DBUtils.closeConnection(conn); 9\AS@SH{^T
} wlr Ign%
} 7H%_sw5S.
public long getLast(){ uJY.5w
return lastExecuteTime; =5ug\S
} [t{](-
public void run(){ .a,(pq Jg
long now = System.currentTimeMillis(); 088C|
if ((now - lastExecuteTime) > executeSep) { LJWTSf"f?
//System.out.print("lastExecuteTime:"+lastExecuteTime); _dr*`yXi
//System.out.print(" now:"+now+"\n"); 3za`>bUN
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); j7}lF?cJ2
lastExecuteTime=now; MKC$;>i
executeUpdate(); V\AK6U@r^
} 0~]QIdu{AR
else{ 'irGvex
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); E_3r[1l
} /'4Q{8.a
} EjSD4
} yp p 4L|R
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释
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类写好了,下面是在JSP中如下调用。 ;g9% &
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<% J)*8|E9P
CountBean cb=new CountBean(); s`c?:
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); j=W@P-
CountCache.add(cb); C`0%C7
out.print(CountCache.list.size()+"<br>"); |{f~Ks%
CountControl c=new CountControl(); VjB*{,
c.run(); kwlC[G$j7
out.print(CountCache.list.size()+"<br>"); #V[SQ=>x[
%>