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: RrKfTiK H
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CountBean.java J"5jy$30'$
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/* [7'#~[a~
* CountData.java 6zv;lx0<D&
* r)OO&. P@j
* Created on 2007年1月1日, 下午4:44 wL Y#dm
* c%ZeX%p
* To change this template, choose Tools | Options and locate the template under sw [oQ!f
* the Source Creation and Management node. Right-click the template and choose '/ihL^^@L
* Open. You can then make changes to the template in the Source Editor. Q,D0kS P
*/ ;]{{)dst
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package com.tot.count; O%fUm0O d
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/** %)8d{1at
* 09G9nu ;&{
* @author ax<g0=^R
*/ D*CIE\+
public class CountBean { I<c@uXXV;!
private String countType; 4pLQ"&>}80
int countId; @55bE\E?@
/** Creates a new instance of CountData */ MJ1W*'9</W
public CountBean() {} _t$lcOT
public void setCountType(String countTypes){ XI]OA7Zis
this.countType=countTypes; *4-r`k|@>/
}
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public void setCountId(int countIds){ P)Z/JHB
this.countId=countIds; +xn&K"]:3
} b;Hm\aK
public String getCountType(){ V/`#B$6
return countType; M_qP!+Y
} w/qQ(]n8
public int getCountId(){ _2]e1_=
return countId; o~Bk0V=
} /uC+.B9k
} 5OPS&:
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CountCache.java !8wZw68"
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/* `K$:r4/[
* CountCache.java h{Oz*Bq
* }9MW!Ss
* Created on 2007年1月1日, 下午5:01 A28ZSL
* Iu)L3_+
* To change this template, choose Tools | Options and locate the template under +#|'|}j
* the Source Creation and Management node. Right-click the template and choose r0~ 7v1rG
* Open. You can then make changes to the template in the Source Editor. 3{ .9O$
*/ 38"8,k
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package com.tot.count; 1h#w"4
import java.util.*; N2[, aU
/** )v*v
* ~J8cS
* @author |usnY
*/ [{6&.v
public class CountCache { /.pa
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public static LinkedList list=new LinkedList(); )OARO
/** Creates a new instance of CountCache */ FiV^n6-F`
public CountCache() {} R*JOiVAC
public static void add(CountBean cb){ 7VEt4
if(cb!=null){ f9h:"Dnzin
list.add(cb); ;cS~d(%
} m
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} H;7O\
} Wh#_9);
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CountControl.java *X-~TC0
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/* UDIac;vT
* CountThread.java R7\{w(`K
* |R_xY=z?
* Created on 2007年1月1日, 下午4:57 t[H _6)
* j8D$/
* To change this template, choose Tools | Options and locate the template under
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* the Source Creation and Management node. Right-click the template and choose
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* Open. You can then make changes to the template in the Source Editor. ~{{:-XkVB
*/ 6= D;K.!
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package com.tot.count; 9wzYDKN}
import tot.db.DBUtils; .`9KB3
import java.sql.*; 75ob1h"
/** ^~$
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* 8X5XwFf}
* @author W1z5|-T
*/ ~heF0C_
public class CountControl{ J %t1T]y~
private static long lastExecuteTime=0;//上次更新时间 XhiC'.B_
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 b6ddXM\Z
/** Creates a new instance of CountThread */ h9mR+ng*oD
public CountControl() {} E'}$'n?:
public synchronized void executeUpdate(){ #SmWF|/
Connection conn=null; t+tGN\q
PreparedStatement ps=null; Z:{Z&HQC
try{ kaLRI|hC
conn = DBUtils.getConnection(); "Y+`U
conn.setAutoCommit(false); &}ow-u9c3
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); YL+W4ld
for(int i=0;i<CountCache.list.size();i++){ Fk\xq`3'c
CountBean cb=(CountBean)CountCache.list.getFirst(); }Z|a?J@CZm
CountCache.list.removeFirst(); ~[{| s')
ps.setInt(1, cb.getCountId()); e;$s{CNo
ps.executeUpdate();⑴ ]z,?{S
//ps.addBatch();⑵ 7gkHKdJoMA
} v3B
^d}+.
//int [] counts = ps.executeBatch();⑶ \[BnAgsF
conn.commit(); Hs9uDGWp
}catch(Exception e){ sgX~4W"J
e.printStackTrace(); q)/4i9
} finally{ {!w]t?h
try{ d@<XR~);
if(ps!=null) { Z-p_hN b
ps.clearParameters(); 8dv1#F|
ps.close(); "](~VF[J8
ps=null; _Cs.%R!r
} e:#\Oh
}catch(SQLException e){} `?)i/jko"
DBUtils.closeConnection(conn); #KIHq2:.4
} 1~+w7Ar=(
} CAX U
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public long getLast(){ 8L#sg^1V
return lastExecuteTime; B\Uj
} ~HELMS~-
public void run(){ QAR<.zXvP
long now = System.currentTimeMillis(); cj[y]2{1h
if ((now - lastExecuteTime) > executeSep) { gG}<l ':
//System.out.print("lastExecuteTime:"+lastExecuteTime); ;y"DEFs,u
//System.out.print(" now:"+now+"\n"); qU"+0t4
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); j8lbn |.
lastExecuteTime=now; (qaY,>je]D
executeUpdate(); 'b-}KDP
} EfOJ%Xr[,l
else{ H)5]K9D
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); P63f0F-G
} noacnQ_I$
} z2r{AQ.&
} E]68IuP@'
//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 Uu
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类写好了,下面是在JSP中如下调用。 J<'4(}^|
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<% FsD}Nk=m~
CountBean cb=new CountBean(); =ahD'*R^A
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); gI T3A*x
CountCache.add(cb); MA`.&MA.
out.print(CountCache.list.size()+"<br>"); D`9 a"o
CountControl c=new CountControl(); 8el\M/u{
c.run(); l/i7<