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:
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CountBean.java HnY: gu
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/* X,y$!2QI
* CountData.java )$th${pd#v
* Uj!L:u2b
* Created on 2007年1月1日, 下午4:44 4
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* @&EP&
$*
* To change this template, choose Tools | Options and locate the template under $7BD~U
* the Source Creation and Management node. Right-click the template and choose k?S-peyRO
* Open. You can then make changes to the template in the Source Editor. Qz$.t>@V=
*/ G53!wIW2:
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package com.tot.count; K} ;uH,
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/** ?^"S%Vb
* pbgCcO~xm
* @author 5@v!wms
*/ [xE\IqwM
public class CountBean { ~?L. n:wu
private String countType; ol:_2G2xQ
int countId; ;c;;cJc!
/** Creates a new instance of CountData */ wwpvmb
public CountBean() {} oa9T3gQ?
public void setCountType(String countTypes){ -7pZRnv
this.countType=countTypes; 9k*'5(D4S
} Y.}n ,y|J}
public void setCountId(int countIds){ wEkW=
this.countId=countIds; `q5*VqIhs
} QTLOP~^
public String getCountType(){ >G-D& A+
return countType; ?EpY4k8,
} ;XTP^W!6f
public int getCountId(){ !D6@ \
return countId; ml3]CcKn
} ~Aq UT]l
} RWoa'lnu
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CountCache.java 2smLv1w@
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/* CF$^we
* CountCache.java YL{LdM-xM
* w-\GrxlbX
* Created on 2007年1月1日, 下午5:01 Qb SX'mx<
* c5t?S@b
* To change this template, choose Tools | Options and locate the template under "0]i4d1l
* the Source Creation and Management node. Right-click the template and choose U9;AU]A
* Open. You can then make changes to the template in the Source Editor. Uq[NOJC
*/ gGZ$}vX
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package com.tot.count; fo5!d@Nv
import java.util.*; ikofJl]9
/** z}pdcQl#
* ?5+=
* @author J[<:-$E
*/ /O&j1g@
public class CountCache { gN(8T_r
public static LinkedList list=new LinkedList(); K\;b3
/** Creates a new instance of CountCache */ eR;cl$
public CountCache() {} RE*SdazY?
public static void add(CountBean cb){ /gPn2e;
if(cb!=null){ 3
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list.add(cb); jLZ~9FXF2
} \a}%/_M\
} N]5-#
} !rwv~9I
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CountControl.java QRa>W/N
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/* 7
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* CountThread.java WF:i}+g+^
* G-T:7
* Created on 2007年1月1日, 下午4:57 y&SueU=
* \E0Uj>9+[
* To change this template, choose Tools | Options and locate the template under L.erP*
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* the Source Creation and Management node. Right-click the template and choose 'GNT'y_
* Open. You can then make changes to the template in the Source Editor. 2AU_<Hr6
*/ ^S[Mg6J
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package com.tot.count; zQD$+q5h
import tot.db.DBUtils; J;G+6C$:
import java.sql.*; zf6k%
/** (u RAK
* 6R#f 8
* @author `F(KM '
*/ bl:.D~@
public class CountControl{ jYuH
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private static long lastExecuteTime=0;//上次更新时间 NbfV6$jo
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 -4"E]f
/** Creates a new instance of CountThread */ Oi=kL{DG:s
public CountControl() {} up`!r;5-
public synchronized void executeUpdate(){ {6A3?q
Connection conn=null; &s\w:
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PreparedStatement ps=null; :3u>%
try{ Eiwo==M
conn = DBUtils.getConnection(); @Vc*JEW
conn.setAutoCommit(false); H}X3nl\]
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); {bl^O
for(int i=0;i<CountCache.list.size();i++){ q]<cn2
CountBean cb=(CountBean)CountCache.list.getFirst(); gNN{WFHQX:
CountCache.list.removeFirst(); @e+QGd;}
ps.setInt(1, cb.getCountId()); aQw?r
ps.executeUpdate();⑴ mZ*!$P:vy"
//ps.addBatch();⑵ t&0pE(MO/
} mmEr2\L
//int [] counts = ps.executeBatch();⑶ Qnph?t>
conn.commit(); e=TB/W_
}catch(Exception e){ b6Dve]
e.printStackTrace(); X8p-VCkV
} finally{ De\&r~bTW9
try{ h_Q9c
if(ps!=null) { 0I& !a$:
ps.clearParameters(); jj.i W@m
ps.close(); !{"{(h)+@
ps=null; mq su8ti
} 8
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}catch(SQLException e){} ~[ isR|>
DBUtils.closeConnection(conn); kC0F@'D
} )"wWV{k
} -AJe\ J 2
public long getLast(){ 591Syyy
return lastExecuteTime; j8L!miv6
} eDgRYa9\
public void run(){ vG69z&
long now = System.currentTimeMillis(); pjWqI6,
if ((now - lastExecuteTime) > executeSep) { {Jwh .bJ
//System.out.print("lastExecuteTime:"+lastExecuteTime); (
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//System.out.print(" now:"+now+"\n"); f9F@G&&Ugg
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); >2,x#RQs
lastExecuteTime=now; oaM $<
executeUpdate(); -6(C^X%
} vc5g4ud
else{ |fOQm
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); , 0MDkXb
} 8|OsVIe%
} pMKnA.|
} ^ ,d!K2`
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 w:#yu
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类写好了,下面是在JSP中如下调用。 6`+dP"@
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<% V^As@P8,'(
CountBean cb=new CountBean(); k$j>_U? P
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 6DD"Asi+
CountCache.add(cb); nM>oG'm[n
out.print(CountCache.list.size()+"<br>"); :]v%6i.
CountControl c=new CountControl(); sjvlnnO
c.run(); NVAt-u0LB
out.print(CountCache.list.size()+"<br>"); yL7D;<!S&
%>