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: <U}25AR
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CountBean.java GPAz#0p
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/* JY9hD;`6y
* CountData.java U\q?tvn'J
* d3 p;[;`
* Created on 2007年1月1日, 下午4:44 D7C%Y^K]>E
* zc1~ q
* To change this template, choose Tools | Options and locate the template under f.RwV+lq
* the Source Creation and Management node. Right-click the template and choose 85](,YYz
* Open. You can then make changes to the template in the Source Editor. { /Gm|*e{
*/ W|6.gN]
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package com.tot.count; bQwiJ`B&
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/** wEEFpn_
* >+S* Wtm5
* @author 84gj%tw'-
*/ Ws[d. El
public class CountBean { _m1WY7
private String countType; X'5+)dj
int countId; u2 U4MV1C
/** Creates a new instance of CountData */ 7T?7KS
public CountBean() {} eD N%p
public void setCountType(String countTypes){ GEAVc9V
this.countType=countTypes; NTSKmCvQG
} {6*{P!H
public void setCountId(int countIds){ u"zQh|
this.countId=countIds; BtP*R,>
} kN*\yH|
public String getCountType(){ mh~n#bah
return countType; cx4'rK.
} 0.!Q4bhD
public int getCountId(){ 5O"wPsl
return countId; q?oJ=]m"
} 7
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} "Oy&6rrr
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CountCache.java G/8G`teAZ
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/* |y2cI,&
* CountCache.java !n5s/"'H
* wq3 V&@.
* Created on 2007年1月1日, 下午5:01 u=6{P(5$j
* :6frx=<
* To change this template, choose Tools | Options and locate the template under z(beT e
* the Source Creation and Management node. Right-click the template and choose Xu\2 2/Co
* Open. You can then make changes to the template in the Source Editor. LWP&Si*j
*/ &?7+8n&+
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package com.tot.count; XcQ'(
import java.util.*; S?m4
/** .:jfNp~jt
* +luW=j0V
* @author "O{:jfq
*/ w5}2$r
public class CountCache { HUY1nb=
public static LinkedList list=new LinkedList(); z/7"!
/** Creates a new instance of CountCache */ Q_n9}LanP
public CountCache() {} R P6R1iN3
public static void add(CountBean cb){ V~qlg1h
if(cb!=null){ cx(b5Z
list.add(cb); 0)3*E)g{
} qbdv
} <S
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} qxglA*/
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CountControl.java rDWqJ<8
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/* `'<&<P
* CountThread.java (6\
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* @y`7csbp
* Created on 2007年1月1日, 下午4:57 `F1 ( v
* xkebel`%
* To change this template, choose Tools | Options and locate the template under g3uI1]QXLg
* the Source Creation and Management node. Right-click the template and choose EYF]&+ 9
* Open. You can then make changes to the template in the Source Editor. kT6EHuB
*/ })}-K7v1+
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package com.tot.count; T Jp0^&Q
import tot.db.DBUtils; :j0r~*z-
import java.sql.*; *S4*FH;8
/** {pNf&'
* 9}6^5f?|
* @author =2[U4<d!R
*/ yasKU6^R'
public class CountControl{ 1(z+*`"WB&
private static long lastExecuteTime=0;//上次更新时间 ocT.2/~d
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 l~Sn`%PgA
/** Creates a new instance of CountThread */ sGD b<
public CountControl() {} Qf]ACN
public synchronized void executeUpdate(){ SpUcrK;1
Connection conn=null; M0zlB{eH
PreparedStatement ps=null; /0H39]y!~
try{ A">A@`}
conn = DBUtils.getConnection(); -!]dU`:(X
conn.setAutoCommit(false); nY<hfqof
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); MM%c
for(int i=0;i<CountCache.list.size();i++){ nfMQ3KP
CountBean cb=(CountBean)CountCache.list.getFirst(); 8"g.Z*
CountCache.list.removeFirst(); e
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ps.setInt(1, cb.getCountId()); )v67wn*1A
ps.executeUpdate();⑴ i;$'haK<
//ps.addBatch();⑵ Lqv5"r7eV
} ]n:)W.|`R
//int [] counts = ps.executeBatch();⑶ r:Xui-
conn.commit(); xd H*[
}catch(Exception e){ ]OOL4=b
e.printStackTrace(); 0oi
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} finally{ \'40u|f
try{ K}U}h>N
if(ps!=null) { bh1WD_
ps.clearParameters(); W@x
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ps.close(); z_p/.kQ'5
ps=null; *tda_B
2
} 43Yav+G(+
}catch(SQLException e){} <j.bG 7
DBUtils.closeConnection(conn); }$ Am;%?p
} 6Hn3
} !%?X% @9
public long getLast(){ WeTs va+
return lastExecuteTime; -)tu$W*
} r='"X#CmV/
public void run(){ dviL5Eaj
long now = System.currentTimeMillis(); pU*dE
if ((now - lastExecuteTime) > executeSep) { ,]'?Gd
//System.out.print("lastExecuteTime:"+lastExecuteTime); ZAPT5
//System.out.print(" now:"+now+"\n"); Hs+VA$$*
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); "oYyeT
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lastExecuteTime=now; [a*m9F\ ,
executeUpdate(); M"]~}*
} mq?5|`
else{ RYaf{i`
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 8 JUUK(&Z
} !RnO{FL
} \gL
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} 3~4e\xL
//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 & ;+u.X
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类写好了,下面是在JSP中如下调用。 wvm`JOP:A
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<% "S43:VH
CountBean cb=new CountBean(); KFd"JtPg
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); d\dt}&S 5
CountCache.add(cb); Eq9TJt'3y
out.print(CountCache.list.size()+"<br>");
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CountControl c=new CountControl(); bO:Ei
c.run(); 78\:{i->ta
out.print(CountCache.list.size()+"<br>"); (@dh"=Lt\
%>