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: CW
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CountBean.java _gw paAJ
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/* a3L-q>h
* CountData.java (*9-Fa
* n?"("Fiw
* Created on 2007年1月1日, 下午4:44 *t_Q5&3L+U
* pA6A*~QE
* To change this template, choose Tools | Options and locate the template under 1Cw
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* the Source Creation and Management node. Right-click the template and choose ~SS3gL v
* Open. You can then make changes to the template in the Source Editor. *Tr9pq%m
*/ B+MnT{
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package com.tot.count; <u/(7H
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/** nPk&/H%5hn
* w-3Lw<
* @author I3u)y|Y=
*/ ZS[Ut
public class CountBean { D"exI]
private String countType; 1u"#rC>7.4
int countId; }b]eiPWN
/** Creates a new instance of CountData */ T3@34}*
public CountBean() {} WEtPIHruyt
public void setCountType(String countTypes){ !|8"}ZF
this.countType=countTypes; &@=W+A=c~
} Hwcm t!y
public void setCountId(int countIds){ Dt(xj}[tC
this.countId=countIds; M 0$E_*
} je%D&ci$
public String getCountType(){ b@O{e QB
return countType; )y{:Uc\4!
} tG~[E,/`
public int getCountId(){ r1 b"ta
return countId; 6[?5hmc"w
} MaPI<kYQv
} [&kz4_
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CountCache.java ';v1AX}5q
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/* 6";
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* CountCache.java "C?H:8W
* @9R78Zra
* Created on 2007年1月1日, 下午5:01 )S;3WnQ)
* 'V&Tlw|
* To change this template, choose Tools | Options and locate the template under /fdrf
* the Source Creation and Management node. Right-click the template and choose zO@>)@~
* Open. You can then make changes to the template in the Source Editor. RT${7=
*/ ~/XDA:nfL:
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package com.tot.count; v]Aop<KLX
import java.util.*; lB.n5G
/** RhC|x,E
* tq?a3
* @author 7C R6ew~
*/ 1 jO%\uR/
public class CountCache { ? a)Fm8Y
public static LinkedList list=new LinkedList(); 0Ua=&;/2
/** Creates a new instance of CountCache */ *F!1xyg
public CountCache() {} nxNHf3
public static void add(CountBean cb){ 1}Y3|QxF
if(cb!=null){ %0 i)l|
list.add(cb); ci/qm\JI<<
} D$@2H>.-
} D c;k)z=
} .(3ec/i4CF
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CountControl.java uP(t+}dQ+3
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/* CD%Cb53
* CountThread.java fI1
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* H8g%h}6h
* Created on 2007年1月1日, 下午4:57 6P:fM Y
* 0a bQY
* To change this template, choose Tools | Options and locate the template under BMdZd5!p&
* the Source Creation and Management node. Right-click the template and choose w)B?j
* Open. You can then make changes to the template in the Source Editor. {&UA60~6
*/ Hp>L}5 y[
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package com.tot.count; WIuYSt)h
import tot.db.DBUtils; o\]U;#YD
import java.sql.*; ]^T-X/v9
/** - Ry+WS=
* ('AAHq/
* @author -e_op'`
*/ )W InPW
public class CountControl{ o8|qT)O@U
private static long lastExecuteTime=0;//上次更新时间 v$w}UC%uf
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 p|8ZHR+
/** Creates a new instance of CountThread */
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public CountControl() {} v/=\(
public synchronized void executeUpdate(){ U| VL+9#hd
Connection conn=null; 79D~Mau#
PreparedStatement ps=null; 0{vH .b
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try{ =5Nh}o(l?
conn = DBUtils.getConnection(); &1R#!|h1W
conn.setAutoCommit(false); &pjj
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); H7z)OaM
for(int i=0;i<CountCache.list.size();i++){ @d^Z^H*Yv
CountBean cb=(CountBean)CountCache.list.getFirst(); J7^UQ
CountCache.list.removeFirst(); $;'M8L
ps.setInt(1, cb.getCountId()); Z) 2d4:uv
ps.executeUpdate();⑴ ~LZrhwVj$
//ps.addBatch();⑵ GZ,MC?W
} =B5{ 7g\
//int [] counts = ps.executeBatch();⑶ N5,LHO
conn.commit(); 7 4MxU
}catch(Exception e){ Mgi~j.[
e.printStackTrace(); p)ig~kk`
} finally{ q6w)zTpJGJ
try{ ~J&-~<%P}
if(ps!=null) { E #B$.K
ps.clearParameters(); J-<_e??
ps.close(); /I!62?)-*
ps=null; yCav;ZS_
} xr7}@rq"U<
}catch(SQLException e){}
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DBUtils.closeConnection(conn); ydo9 P5E
} rq4g~e!S
} Y0T :%
public long getLast(){ af %w|M
return lastExecuteTime; AU}kIm_+
} Nw$OJ9$L>
public void run(){ IGQBTdPUa
long now = System.currentTimeMillis(); M\a{2f7'n
if ((now - lastExecuteTime) > executeSep) { )E*f30
//System.out.print("lastExecuteTime:"+lastExecuteTime); Q;w[o
//System.out.print(" now:"+now+"\n"); 7C0xKF
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); PfRA\
lastExecuteTime=now; *1{A'`.=\
executeUpdate(); v/9ZTd
} .P aDR |!
else{ mL2J
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); :PW"7|c!
} $!MP0f\q
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} 8=TC 3]
} \fiy[W/k
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 /51$o\4S
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类写好了,下面是在JSP中如下调用。 D
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<% A,~KrRd
CountBean cb=new CountBean(); 7@%qm|i>w
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); boGdZ2$h4
CountCache.add(cb); |1(x2x%}D^
out.print(CountCache.list.size()+"<br>"); 6XF Ufi+
CountControl c=new CountControl(); UMe?nAC
c.run(); sTl^j gV7j
out.print(CountCache.list.size()+"<br>"); Eu'E;*-f
%>