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: !D
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CountBean.java %~Ymb&ugg
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/* VdL }$CX$
* CountData.java Kt"4<'
* Us>n`Lj@
* Created on 2007年1月1日, 下午4:44 ]h=y
* JQ]MkP
* To change this template, choose Tools | Options and locate the template under [#:yOZt
* the Source Creation and Management node. Right-click the template and choose p5nrPL
* Open. You can then make changes to the template in the Source Editor. tKi^0vE8
*/ dr"@2=Z
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package com.tot.count; VhgcvS@V
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/** 0|rdI,z
* IPY[x|
* @author q6
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*/ <z
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public class CountBean {
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private String countType; gX5.u9%C\
int countId; [s-!tE3-
/** Creates a new instance of CountData */ bU4\Yu
public CountBean() {} 1eS@ihkP
public void setCountType(String countTypes){ fAT
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this.countType=countTypes; |'L$ogt6
} 'EU|w,GL}
public void setCountId(int countIds){ HhTD/
this.countId=countIds; iSMVV<7
} B@vup {Kg
public String getCountType(){ !ZN"(0#qz
return countType; 'sjks sy.3
} 3"6-X_
public int getCountId(){ BQ!_i*14+
return countId; A6Wtzt2i
} 4?x$O{D5?{
} p1\EC#Q
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CountCache.java UzkX;UA
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/* xl@
* CountCache.java ~</H>Jd
* <QK2Wc_}-"
* Created on 2007年1月1日, 下午5:01 4e|(= W`
* }M(XHw
* To change this template, choose Tools | Options and locate the template under yjChnp
Cc
* the Source Creation and Management node. Right-click the template and choose zhACNz4tJ
* Open. You can then make changes to the template in the Source Editor. 7(zY:9|(
*/ :\#/T,K"
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package com.tot.count; ~uO9>(?D
import java.util.*; m\|ie8
/** kQtnT7
* I9jzR~T
* @author Z&y9m@
*/ /}-LaiS
public class CountCache { &?SU3@3|
public static LinkedList list=new LinkedList(); `H|#l\
/** Creates a new instance of CountCache */ [PU0!W;
public CountCache() {} !~f!O"n)3r
public static void add(CountBean cb){ F:2V;
if(cb!=null){ a#P{ [
list.add(cb); ey[+"6Awne
} d?OsVT;U
} AkV8}>G?#A
} Y/n],(t)
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CountControl.java =MMSmu5!
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/* Q-f?7*>
* CountThread.java Gn?<~8a
* !\1Pu|
* Created on 2007年1月1日, 下午4:57 O<qo%fP
* 6y)NH 8l7
* To change this template, choose Tools | Options and locate the template under 5!d'RBO
* the Source Creation and Management node. Right-click the template and choose oOy_2fwZPp
* Open. You can then make changes to the template in the Source Editor. G9a6 $K)b
*/ {rZ )!
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package com.tot.count; Q>>II|~;J
import tot.db.DBUtils; K<ok1g'0
import java.sql.*; \@:mq]Y
/** LD)P.
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* xw&N[y5
* @author {vAv ;m
*/ o51jw(wO
public class CountControl{ dht*1i3v
private static long lastExecuteTime=0;//上次更新时间 g%f6D%d)A
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 <>6 DPHg~
/** Creates a new instance of CountThread */ 6J%yo[A(w
public CountControl() {} [>U =P`
public synchronized void executeUpdate(){ NYp46;
Connection conn=null; 3 n=ftkI
PreparedStatement ps=null; .uu[MzMIu
try{ XSz)$9~hk
conn = DBUtils.getConnection(); ~i/K7qZ
conn.setAutoCommit(false); xsdi\
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ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 0:4w@"Q
for(int i=0;i<CountCache.list.size();i++){ qEV>$>}
CountBean cb=(CountBean)CountCache.list.getFirst(); ju?D=n@i
CountCache.list.removeFirst(); G^/8lIj
ps.setInt(1, cb.getCountId()); rnTjw
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ps.executeUpdate();⑴ TbA=bkj[4
//ps.addBatch();⑵ \ POQeZ
} X=i",5;
//int [] counts = ps.executeBatch();⑶ _V-pr#lP1
conn.commit(); XhG3Of-6
}catch(Exception e){ 16R0#Q/{+*
e.printStackTrace(); l|&DI]gw
} finally{ 0P_3%
try{ use`
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if(ps!=null) { ptEChoZ6
ps.clearParameters(); h1.<\GO
ps.close(); Y|96K2BR
ps=null; /#I~iYPe
} HH94?&
}catch(SQLException e){} 80;^]l
DBUtils.closeConnection(conn); lcYjwA
} C;NG#4;'
} -7:_Dy
public long getLast(){ (S1Co&SX
return lastExecuteTime; 1=Nh<FuQ
} ct![eWsuB
public void run(){ ~zT7 43
long now = System.currentTimeMillis(); R\d)kcy4
if ((now - lastExecuteTime) > executeSep) { tKKQli4Mn4
//System.out.print("lastExecuteTime:"+lastExecuteTime); ,c9K]>8m`
//System.out.print(" now:"+now+"\n"); &pZncm
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); RYuR&0_{
lastExecuteTime=now; zyi;vu
executeUpdate(); wmnh7'|0u
} MGE8S$Z
else{ QNesiV0MI
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); wPrqFpf
} /[RO>Z9
} #[.aj2
}
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//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 %d"d<pvx
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类写好了,下面是在JSP中如下调用。 _?QVc0S!
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<% x|lX1Mh$
CountBean cb=new CountBean(); =/SBZLR(9
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); !{%BfZX<&
CountCache.add(cb); dNfME*"yN
out.print(CountCache.list.size()+"<br>"); >s|zrS)
CountControl c=new CountControl(); X/' t1
c.run(); 'sT7t&v~
out.print(CountCache.list.size()+"<br>"); EwKFT
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