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&xj(SMj-$
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CountBean.java uNyN[U
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/* EyA
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* CountData.java <}{<FXk[
* )-)rL@s.
* Created on 2007年1月1日, 下午4:44 MOaI~xZ
* ))|d~m
* To change this template, choose Tools | Options and locate the template under T:@6(_Z
* the Source Creation and Management node. Right-click the template and choose yogavCD9b/
* Open. You can then make changes to the template in the Source Editor. W-s 6+DY
*/ N<rq}^qo
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package com.tot.count; HfVHjF)
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/** K'Ywv@
* 2j%=o?me^p
* @author wBXa;.
*/ ay7\Ae]
public class CountBean {
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private String countType; Lxp}o7>K
int countId; zK5&,/
/** Creates a new instance of CountData */ ,6;n[p"h|r
public CountBean() {} 6U*CR=4
public void setCountType(String countTypes){ 6^LXctW.
this.countType=countTypes; zX_F+"]THt
} O3o^%0
public void setCountId(int countIds){ MRt"#CO
this.countId=countIds; metn&
} mxgT}L0i
public String getCountType(){ i#*[,
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return countType; uAA2G\3
} e^O:I
public int getCountId(){ F;ttqL
return countId; r&4Xf#QD6
} =;0-t\w!
} q!:dZES
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CountCache.java R BHDfm'~7
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/* MT~^wI0a
* CountCache.java !YAX.e
* k5Cy/gR
* Created on 2007年1月1日, 下午5:01 -4Hb]#*2
* Q0R05*
* To change this template, choose Tools | Options and locate the template under =l43RawAmu
* the Source Creation and Management node. Right-click the template and choose a
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* Open. You can then make changes to the template in the Source Editor. -13}]Gls7Q
*/ 9-T<gYl
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package com.tot.count; Pb'(Y
import java.util.*; x;7l>uR
/** t,fec>.
* uM`i!7}
* @author dBd7#V:}yV
*/ )ovAG O
public class CountCache { RlL]p`g
public static LinkedList list=new LinkedList(); l'(FM^8jv
/** Creates a new instance of CountCache */ v
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public CountCache() {} ~ZVz
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public static void add(CountBean cb){ |iHMAo
if(cb!=null){ g& e u
list.add(cb); \lQ3j8U
} bIiuna\
} k4V3.i!E
} ?-)!dl%N
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CountControl.java -r sbSt ?_
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/* &K0b3AWc
* CountThread.java */M`KPW
* B%6cgm,
* Created on 2007年1月1日, 下午4:57 {jO+N+Ez9
* F
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* To change this template, choose Tools | Options and locate the template under 1GK.:s6.f
* the Source Creation and Management node. Right-click the template and choose V gMgeja
* Open. You can then make changes to the template in the Source Editor. ]_h3
*/ I%J>~=]n_
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package com.tot.count; cZBXH*-M!
import tot.db.DBUtils; ,kJ7c;:i
import java.sql.*; >O\+ 9T@
/** CK n2ZL
* _dm0*T ?
* @author @KL&vm(F$
*/ F^gTID
public class CountControl{ Bn]=T
private static long lastExecuteTime=0;//上次更新时间 E_=F'sP?
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 jXeE]A"
/** Creates a new instance of CountThread */ T>asH
public CountControl() {} .1[.f}g$J
public synchronized void executeUpdate(){ 4 -tC=>>wc
Connection conn=null; 7zH2dqrj
PreparedStatement ps=null; QZ&(e2z
try{ [cnuK
conn = DBUtils.getConnection(); o>8~rtl
conn.setAutoCommit(false); <Ja&z M
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 1+Gq<]@G
for(int i=0;i<CountCache.list.size();i++){ T]wI)
CountBean cb=(CountBean)CountCache.list.getFirst(); 1M&Lb.J6
CountCache.list.removeFirst(); Ge`7`D>L
ps.setInt(1, cb.getCountId()); jlP*RX
ps.executeUpdate();⑴ Sh!c]r>\Q
//ps.addBatch();⑵ `*vO8v
} l48$8Mgrr
//int [] counts = ps.executeBatch();⑶ *gwaW!=
conn.commit(); 44*#qLN
}catch(Exception e){ @6G)(NGD
e.printStackTrace(); OY{fxBb
} finally{ ;"nO'wN:h
try{ eP]y\S*P
if(ps!=null) { 7.Y;nem:(
ps.clearParameters(); HZAT_
ps.close(); o5s6$\"
ps=null; vm|u~Yd,s
} +H3~Infr4f
}catch(SQLException e){} `;}`>!8j
DBUtils.closeConnection(conn); B`-uZ9k
} Sn*s@RE\s
} "?zWCH
public long getLast(){ zj r($?
return lastExecuteTime; eV*QUjS~
} qI uo8o}
public void run(){ ,<L4tp+y0
long now = System.currentTimeMillis(); r[!~~yu/o
if ((now - lastExecuteTime) > executeSep) { 16/ V5
//System.out.print("lastExecuteTime:"+lastExecuteTime); 06&;GW!-
//System.out.print(" now:"+now+"\n"); W$`v^1M2o
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); `e,}7zGR
lastExecuteTime=now; m
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executeUpdate(); .rk5u4yK
} s-rc0:I
else{ o)5zvnu7
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); twr{jdY9
} v,}C~L3
} n0 l|7:Mk
} +zMhA p
//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 )r46I$]>
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类写好了,下面是在JSP中如下调用。 +
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<% Fl.?*KBz
CountBean cb=new CountBean(); V|
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); c)#7T<>*'
CountCache.add(cb); q.=Q
out.print(CountCache.list.size()+"<br>"); H7+z"^s*
CountControl c=new CountControl(); "~ID.G|<
c.run(); :'bZ:J>f
out.print(CountCache.list.size()+"<br>"); /}@F
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