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: iYr)Ao5X
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CountBean.java wa@Rlzij>
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/* wh(_<VZ
* CountData.java KkUK" Vc
* KPToyCyR1
* Created on 2007年1月1日, 下午4:44 A}lxJ5h0
* 'pt(
* To change this template, choose Tools | Options and locate the template under D W U=qD+
* the Source Creation and Management node. Right-click the template and choose Ur+U#}
* Open. You can then make changes to the template in the Source Editor. /bykIUTKI
*/ ]zYIblpde
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package com.tot.count; X(tx8~z
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/** [l-o*@
* DZqG7p$u4i
* @author Sn[xI9}O
*/ 5M=U*BI
public class CountBean { DQ8/]Z{H
private String countType; 0h1u W26^
int countId; x+Yo#u22
/** Creates a new instance of CountData */ yhKH}
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public CountBean() {} '#c#.O
public void setCountType(String countTypes){ ?;RY/[IX6
this.countType=countTypes; uqcG3Pi
} U$5x#{AFp
public void setCountId(int countIds){ J?V$V
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this.countId=countIds; 2B4.o*Q\
} TyV~2pcN
public String getCountType(){ L!:NL#M
return countType; I7_8oq\3D
} k<1i.rh
public int getCountId(){ G
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return countId; _|\X8o_
} 0f5 ag&
} -1dD~S$
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CountCache.java &KMI C
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/* N)mZ!K44
* CountCache.java ?pIELezfK
* ` +YtTK
* Created on 2007年1月1日, 下午5:01 <Z.`X7]Uk
* JLm3qIC
* To change this template, choose Tools | Options and locate the template under Dspvc
* the Source Creation and Management node. Right-click the template and choose Pyuul4(
* Open. You can then make changes to the template in the Source Editor. vP,pK=5
*/ Zd-qBOB2L
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package com.tot.count; hr]+4!/
import java.util.*; Vja 4WK*
/** Un8' P8C
* (RI)<zaK
;
* @author %ap]\o$^4
*/ $*eYiz3Ue
public class CountCache { [CEV&B
public static LinkedList list=new LinkedList(); "3VX9{'%@
/** Creates a new instance of CountCache */ qoZi1,i'
public CountCache() {} s O#cJAfuu
public static void add(CountBean cb){ /}1|'?P
if(cb!=null){ z9
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list.add(cb); P
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} <6;M\:Y*T
} pmP~1=3
} `]65&hWZL
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CountControl.java Y[e.1\d'
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/* gE #|eiu
* CountThread.java (87wWhH
* z#!<[**&
* Created on 2007年1月1日, 下午4:57 Aq(cgTNW
* W^09tx/I
* To change this template, choose Tools | Options and locate the template under 07SW$INb
* the Source Creation and Management node. Right-click the template and choose O`CZwXD
* Open. You can then make changes to the template in the Source Editor. S$SCW<LuN
*/ /\Nc6Z/ L
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package com.tot.count; P]m{\K
import tot.db.DBUtils; D 6'd&U{_
import java.sql.*; @N '_qu
/** ;uAh)|;S#
* >e;jGk?-
* @author /
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*/ 1
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public class CountControl{ ~Q=;L>Qd
private static long lastExecuteTime=0;//上次更新时间 1$DcE>
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 oC"
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/** Creates a new instance of CountThread */ }Nn+Ny
public CountControl() {} ->pU!f)\X
public synchronized void executeUpdate(){ _f2rz+
Connection conn=null; 8L:AmpQdpA
PreparedStatement ps=null; mKtMI!FR
try{ U;3t{~Ym
conn = DBUtils.getConnection(); }o]}R#|
conn.setAutoCommit(false); A)~oD_ooQ
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ;F1y!h67<
for(int i=0;i<CountCache.list.size();i++){ Ru
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CountBean cb=(CountBean)CountCache.list.getFirst(); N'{Yhx u
CountCache.list.removeFirst(); ~I N g9|
ps.setInt(1, cb.getCountId()); :kcqf,7
ps.executeUpdate();⑴ &(<>}
r
//ps.addBatch();⑵ <`-sS]=d}
} o.Ww.F
//int [] counts = ps.executeBatch();⑶ fwUvFK1G
conn.commit(); .]exY
i
}catch(Exception e){ jhz*Y}MX
e.printStackTrace(); )j'Qi^;(D
} finally{ /*gs]
try{ {QG6ldI
if(ps!=null) { >#n"r1
ps.clearParameters(); !DA4q3-U>>
ps.close(); q;R&valn
ps=null; cL .z{
} i'CK/l.H
}catch(SQLException e){} YL`ML t4MC
DBUtils.closeConnection(conn); ]UIN4E
} 'O 7:=l
} v2rzHzFU
public long getLast(){ (soTkH:#
return lastExecuteTime; c^"4l
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} nv0D4 t
public void run(){ OE[7fDe'
long now = System.currentTimeMillis(); 5X3JQ"z
if ((now - lastExecuteTime) > executeSep) { 7]So=%q
//System.out.print("lastExecuteTime:"+lastExecuteTime); LTBH/[q5
//System.out.print(" now:"+now+"\n"); X)(K|[
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); QpzdlB44l
lastExecuteTime=now; ?$)a[UnqX
executeUpdate(); <9H3d7%
} D4"<suU|.
else{ Otr=+i
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//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); :?EZ\WM7
} Lm!]m\LRZD
} C!547(l[
} 29 !QE>Q
//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 &!;o[joG
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类写好了,下面是在JSP中如下调用。 ((AK7hb
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<% {88|J'*L
CountBean cb=new CountBean(); ~Ih`
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); e4_A`j'
CountCache.add(cb); IW@xT@
out.print(CountCache.list.size()+"<br>"); Tn,_0
CountControl c=new CountControl(); 8S#&XS>o
c.run(); p4O[X\T
out.print(CountCache.list.size()+"<br>"); nQ'NS
%>