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: i)\`"&.j>N
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CountBean.java GdR>S('
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/* {J%hTjCw
* CountData.java /Yc!m$uCW
* '@wYr|s4
* Created on 2007年1月1日, 下午4:44 J& +s
* kYz)h
* To change this template, choose Tools | Options and locate the template under X\hD4r"
* the Source Creation and Management node. Right-click the template and choose X^?<, Y)1.
* Open. You can then make changes to the template in the Source Editor. FJv=5L
*/ (zBa2Vmmv
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package com.tot.count; 6
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/** RP7e)?5$s
* XY1NTo.=
* @author ${KDGJ,^
*/ *(s+u~, I
public class CountBean { ?.IT!M}DR
private String countType; y)|Q~8r
int countId; ! k||-Q&
/** Creates a new instance of CountData */ V{$(#r
public CountBean() {} ?y'KX]/
public void setCountType(String countTypes){ -Duy:C6W
this.countType=countTypes; +%6{>C+bZo
} S3:Pjz}t
public void setCountId(int countIds){ J+[&:]=P
this.countId=countIds; ,2[laJ
} u1ggLH!U
public String getCountType(){ e1S |&W8
return countType; vX)JJ|g
} 4/S4bk*8
public int getCountId(){ 7h<Q{X<A
return countId; n%3rv?m7
} 2JYyvJ>
} /Bid:@R
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CountCache.java OTL=(k
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/* ~LuZpV
* CountCache.java IBf&'/ 8\
* rv&(yA
* Created on 2007年1月1日, 下午5:01 s,"<+80%
* Bra>C
* To change this template, choose Tools | Options and locate the template under <G{m=
* the Source Creation and Management node. Right-click the template and choose ?2%d;tW
* Open. You can then make changes to the template in the Source Editor. h5U@Ys
*/ -B9C2
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package com.tot.count; #c'yAa
import java.util.*; F5gL-\6
/** V?
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* 8uM >Up X
* @author #!OCEiT_
*/ KFdV_e5lU
public class CountCache { nyi}~sB
public static LinkedList list=new LinkedList();
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/** Creates a new instance of CountCache */ f`.8.1Rd
public CountCache() {} O>wGc8Of\
public static void add(CountBean cb){ vJ7I
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if(cb!=null){ LgjL+w19
list.add(cb); "'4R_R
}
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} L|qQZ=
} w W1aG
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CountControl.java KIC5U50J
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/* &xgMqv2/
* CountThread.java s-}|_g.Pt
* JWr:/?
* Created on 2007年1月1日, 下午4:57 bA@!0,m
* KF|+#qCN
* To change this template, choose Tools | Options and locate the template under n&D<l '4
* the Source Creation and Management node. Right-click the template and choose Z%y>q|:
* Open. You can then make changes to the template in the Source Editor. !Sy._NE`z
*/ _Buwz_[&
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package com.tot.count; dD?1te
import tot.db.DBUtils; ';hU&D;s
import java.sql.*; lt|\$Iy(
/** o=_:g >5
*
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* @author Yewn
*/ cNtGjLpx;
public class CountControl{ Ah;2\0|t
private static long lastExecuteTime=0;//上次更新时间 & 1p\.Y
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 Ds9pXgU(Z
/** Creates a new instance of CountThread */ L)a8W
public CountControl() {} OKNA36cU'
public synchronized void executeUpdate(){ h=.|!u
Connection conn=null; nW3-)Q89
PreparedStatement ps=null; yMq&9R9F
try{ UQ:H3
conn = DBUtils.getConnection(); .mn`/4
conn.setAutoCommit(false); NKvBNf|D
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); dFS>uIT7X
for(int i=0;i<CountCache.list.size();i++){ :.'<ndM
CountBean cb=(CountBean)CountCache.list.getFirst(); &M,a+|yuY
CountCache.list.removeFirst(); cTCo~Pk4
ps.setInt(1, cb.getCountId()); l)[\TD
ps.executeUpdate();⑴ n1 =B
//ps.addBatch();⑵ q&Y'zyHLP
} QM2Y?."#
//int [] counts = ps.executeBatch();⑶ ;n%SjQ'%
conn.commit(); 8i!AJF9IQ}
}catch(Exception e){ nBI?~hkP3
e.printStackTrace(); u =z$**M^
} finally{ :6S!1roi
try{ VLC<ju!
if(ps!=null) { B]L5K~d
ps.clearParameters(); a|SgGtBtT4
ps.close(); Rq )&v*=
ps=null; QG*=N {%5
} 'A;G[(SYy
}catch(SQLException e){} `uM:>
DBUtils.closeConnection(conn); CnSf GsE>
} hEi]-N\X
} 'iA#lKG
public long getLast(){ 4sasf94
return lastExecuteTime; SeN4gr*
} }l~|c{WH`
public void run(){ L^i=RGx
long now = System.currentTimeMillis(); Nz_c]3_j
if ((now - lastExecuteTime) > executeSep) { M$~3`n*^
//System.out.print("lastExecuteTime:"+lastExecuteTime); $m,gQV~4
//System.out.print(" now:"+now+"\n"); cjAKc|N J
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); <`k\kZM
lastExecuteTime=now; Ni#!C:q
executeUpdate(); P?p>'avP
} 'bJ!~ML&
else{ _*7h1[,{f
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); rl4B(NZi}
} ,(dg]7
} bO 2>ced
} GmP)"@O](;
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 0{^vqh.La
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类写好了,下面是在JSP中如下调用。 u\wdb^8ds
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<% wwrP7T+d
CountBean cb=new CountBean(); Se<]g$eK?5
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); jWJq[l
CountCache.add(cb); 0<_|K>5dS|
out.print(CountCache.list.size()+"<br>"); $3<,"&;Ecs
CountControl c=new CountControl(); 6w(Mb~[n
c.run(); w`=_|4wFw
out.print(CountCache.list.size()+"<br>"); rt%?K.S/
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