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: G{,DoCM5WL
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CountBean.java l{]KA4
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/* m6^#pqSL
* CountData.java _OJfd
* [n&ES\o#(
* Created on 2007年1月1日, 下午4:44 2wPc
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* h-O;5.m-P
* To change this template, choose Tools | Options and locate the template under _iDVd2X"H
* the Source Creation and Management node. Right-click the template and choose R
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* Open. You can then make changes to the template in the Source Editor. oa=TlBk<
*/ *_J{_7pwe
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package com.tot.count; N^wHO<IO1
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/** j+dQI_']x
* ;;
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* @author N(yd<Mw
*/ vf#d
public class CountBean { Sp?e!`|8
private String countType; /:{4,aX2
int countId; L^Q;M,.c;
/** Creates a new instance of CountData */ `:EhYj.
public CountBean() {} G,B4=[Y
public void setCountType(String countTypes){ sSwY!";
this.countType=countTypes; X<$DNRN
} -F*vN'
public void setCountId(int countIds){ Pw +nO
this.countId=countIds; ? EHheZ{
} Qm*ZOz'i
public String getCountType(){ ?*
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return countType; f9<"
} $%M]2_W(
public int getCountId(){ |v :
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return countId; XjP;O,x
} imzPVGCD{
} yH43Yo#Rk
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CountCache.java Ac*J;fI
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/* .m\0<8C
* CountCache.java KZcmNli&A
*
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* Created on 2007年1月1日, 下午5:01 `jr?I {m;
* Ya!%o> J%t
* To change this template, choose Tools | Options and locate the template under RP+)sCh
* the Source Creation and Management node. Right-click the template and choose Wi!"Vcn
* Open. You can then make changes to the template in the Source Editor. TXyiCS3
*/ Px*<-t|R-
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package com.tot.count; |Ox='.oIb
import java.util.*; xYW&Mfka
/** Y.tT#J^=
* zA.0Sm
* @author Q[q`)~|
*/ T*=*$%
public class CountCache { U1lqg?KO
public static LinkedList list=new LinkedList(); &dK!+
/** Creates a new instance of CountCache */ "dDrw ]P;
public CountCache() {} U~"Y8g#qgy
public static void add(CountBean cb){ ,=[%#gS
if(cb!=null){ FY^Nn
list.add(cb); }P{Wk7#Jq
} <Q- m &
} ;y1/b(t
} jf)l; \u
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CountControl.java tk=S4/VWv
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/* ~Fwbi
* CountThread.java <m1v+cnqo
* -MTYtw(
* Created on 2007年1月1日, 下午4:57 Kr|.I2?"
* b.\xPb
* To change this template, choose Tools | Options and locate the template under ).(y#zJ7P
* the Source Creation and Management node. Right-click the template and choose *W^ZXhrZ
* Open. You can then make changes to the template in the Source Editor. r;[ =y<Yf
*/ +DR$ >a
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package com.tot.count; t8xXGWk0
import tot.db.DBUtils; .PR+_a-X
import java.sql.*; J,u-)9yBA<
/** fG$LqzyqlK
* ~gMt
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* @author
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*/ gM=:80
public class CountControl{ m9i/rK_
private static long lastExecuteTime=0;//上次更新时间 qnj'*]ysBC
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 |rZMcl/
/** Creates a new instance of CountThread */ LfFXYX^
public CountControl() {} $YcB=l
public synchronized void executeUpdate(){ w(
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Connection conn=null; SUUN_w~
PreparedStatement ps=null; 4sn\UuKyL
try{ ?7LvJ8
conn = DBUtils.getConnection(); *x;4::'Jn
conn.setAutoCommit(false); : N$-SV
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); CPRVSN0b{4
for(int i=0;i<CountCache.list.size();i++){ {$yju _[
CountBean cb=(CountBean)CountCache.list.getFirst(); /"j3B\`?
CountCache.list.removeFirst(); ;`:YZ+2
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ps.setInt(1, cb.getCountId()); 1,bE[_
ps.executeUpdate();⑴ ,#&7+e!]>P
//ps.addBatch();⑵ 5Lej_uqF
} 51#OlvD
//int [] counts = ps.executeBatch();⑶ +)e|>
conn.commit(); y;8&J{dd
}catch(Exception e){ N1Ag.
e.printStackTrace(); 6b'.WB]-
} finally{ >,]8iMh
try{ *tEqu%N1'
if(ps!=null) { H;=Fq+
ps.clearParameters(); {A:uy
ps.close(); p`c_5!H
ps=null; }AJoF41X
} hp9U
}catch(SQLException e){} A!x &,<
DBUtils.closeConnection(conn); a6e{bAuq
} Q-gVg%'7
} Ihf :k_;
public long getLast(){ y*vSt^
return lastExecuteTime; PMB4]p%o
} ow3.jHsLA
public void run(){ }shxEsq
long now = System.currentTimeMillis(); /kkUEo+
if ((now - lastExecuteTime) > executeSep) { /YF:WKr2
//System.out.print("lastExecuteTime:"+lastExecuteTime); @y`xFPB
//System.out.print(" now:"+now+"\n"); f6`GU$H
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); '= fk;AiQ
lastExecuteTime=now; er)I ".|
executeUpdate(); }>u `8'2v
} \?^2}K/
else{ tMiIlf!>p
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); VoZ{ I{>|
} qVE0[ve
} ~RuX2u-2&u
} f=R+]XPzz
//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 &R_7]f+%)
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类写好了,下面是在JSP中如下调用。 A:r?#7 Ma
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<% &9#m]Mz
CountBean cb=new CountBean(); 6-
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 67&
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CountCache.add(cb); &S*~EM.l8
out.print(CountCache.list.size()+"<br>"); K?!qNK
CountControl c=new CountControl(); IL %]4,
c.run(); DdgiY9a.
out.print(CountCache.list.size()+"<br>"); 6&eXQl
%>