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: /T53"+7:0
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CountBean.java bT^6AtsJ
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/* h/7m.p]
* CountData.java 2m]CmdV^
* +}eGCZra
* Created on 2007年1月1日, 下午4:44 Dp)5u@I
* z@Klj qN
* To change this template, choose Tools | Options and locate the template under tnv @`xBn
* the Source Creation and Management node. Right-click the template and choose sYQ=nL
* Open. You can then make changes to the template in the Source Editor. owz6j:
*/
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package com.tot.count; q97Z .o
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/** jF5Y-CX
* hRU.^Fn#%
* @author Sn(e@|!G
*/ bq mb|mD
public class CountBean { ;7jszs.6%
private String countType; #GTR}|Aga
int countId; :qfP>Ok
/** Creates a new instance of CountData */ qhFWQ1W
public CountBean() {} F/91Es
public void setCountType(String countTypes){ 7r F )fKW
this.countType=countTypes; 5crd.1@^
} N:"S/G>r ;
public void setCountId(int countIds){ ?AMn>v
this.countId=countIds; !fwMkws
} G?p !*7N
public String getCountType(){ avJ%J"j8z
return countType; ?pE)K<+Zkf
} k0@b"y*
public int getCountId(){ C`4m#
return countId; >(>,*zP<9
} _,,w>q6K
} _>b=f
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CountCache.java Bri yy
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/* })v`` +
* CountCache.java zv~dW4'
* v-
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* Created on 2007年1月1日, 下午5:01 ^Z
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* /6K9? /
* To change this template, choose Tools | Options and locate the template under A_:CGtv:
* the Source Creation and Management node. Right-click the template and choose cdBD.sg
* Open. You can then make changes to the template in the Source Editor. h83W;s
*/ 5]-q.A5m
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package com.tot.count; YadG05PDe
import java.util.*; \
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/** VxgP^*
* ,/oqLI\
* @author mz[Q]e~&i
*/ _Se0,Uns
public class CountCache { >cTSX
public static LinkedList list=new LinkedList(); |TQ#[9C0
/** Creates a new instance of CountCache */ -Lo3@:2i
public CountCache() {} sz"N,-<Ig
public static void add(CountBean cb){ d~0k}|>
if(cb!=null){ lG1\41ZxB
list.add(cb); PLb[U(~
} _A>?@3La9
} TJO?BX_9
} }zO>y%eI
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CountControl.java }wIF$v?M
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/* 'PS_|zI
* CountThread.java S/2lK*F
* J4woZ{d
* Created on 2007年1月1日, 下午4:57 _k|k$qxE
* "Dt:
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* To change this template, choose Tools | Options and locate the template under pXhN? joe
* the Source Creation and Management node. Right-click the template and choose A!:R1tTR;S
* Open. You can then make changes to the template in the Source Editor. |uIgZ|7[
*/ o..iT:f;n
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package com.tot.count; JeXA*U#
import tot.db.DBUtils; 1_B;r9x
import java.sql.*; *-vH64e
/** =mp"=%
* r .`&z
* @author v[b|J7k
*/ }~+q S`
public class CountControl{ nw
private static long lastExecuteTime=0;//上次更新时间 1G}\IK1+
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 W%-`
/** Creates a new instance of CountThread */ ;uhpo
public CountControl() {} GQ8A}gwH
public synchronized void executeUpdate(){ u$Wv*;TT%
Connection conn=null; |I2~@RfpO:
PreparedStatement ps=null; cl{kCSZo.z
try{ r @URs;O=
conn = DBUtils.getConnection(); g@Z7f y7
conn.setAutoCommit(false); .P(Ax:g
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); peZ'sZ 6
for(int i=0;i<CountCache.list.size();i++){ r]B`\XWz
CountBean cb=(CountBean)CountCache.list.getFirst(); i$g6C
CountCache.list.removeFirst(); p;<aZ&@O
ps.setInt(1, cb.getCountId()); b^'>XT~1J&
ps.executeUpdate();⑴ =KW~k7TaN
//ps.addBatch();⑵ 6[3>[ej:x
} wu;^fL
//int [] counts = ps.executeBatch();⑶ n48%Uwa,
conn.commit(); w gkY\Q
}catch(Exception e){ El^V[s'3
e.printStackTrace(); p7p6~;P
} finally{ QD;:!$Du
try{ C5^9D
if(ps!=null) { wl0 i3)e:
ps.clearParameters(); {O_`eS
ps.close(); ?hOvY)
ps=null; lbj_if;
} hr?0RPp}
}catch(SQLException e){} jyFKO[s\X
DBUtils.closeConnection(conn); D9r4oRkP*
} k&pV`.Imi
} 3a?dNwM@
public long getLast(){ mc|8t0+1`
return lastExecuteTime; iHk/#a
} T1A/>\Ns
public void run(){ O6b.oS'-
long now = System.currentTimeMillis(); t]XF*fZH
if ((now - lastExecuteTime) > executeSep) { }UWi[UgA
//System.out.print("lastExecuteTime:"+lastExecuteTime); la_FZ
//System.out.print(" now:"+now+"\n"); r}|a*dh'R
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); >8EmfjUoc
lastExecuteTime=now; LYMb)=u]
executeUpdate(); ?Vc/mO2X
} qFwAzW;"
else{ Jzj>=jWX@
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); n=%D}W
} $sb `BS
} #F:\_!2c
} 8M6Qn7{L
//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 qR^i5JH}u
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类写好了,下面是在JSP中如下调用。 :pGgxO% q
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<% S,GM!YZg
CountBean cb=new CountBean(); ^03M~SNCj
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 3bR 6Y[
CountCache.add(cb); 7s2e>6Q[
out.print(CountCache.list.size()+"<br>"); m8z414o
CountControl c=new CountControl(); WbHI>tt
c.run(); Z]k+dJ[-
out.print(CountCache.list.size()+"<br>"); 2-DJ3OL]k
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