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: Eg4_kp0Lq
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CountBean.java 8y'.H21:;
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/* 0X4I-xx#
* CountData.java \-CL}Z}S
* .x][ _I>
* Created on 2007年1月1日, 下午4:44 La
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* 4nKlW_{,
* To change this template, choose Tools | Options and locate the template under o "1X8v
* the Source Creation and Management node. Right-click the template and choose )wCV]TdF
* Open. You can then make changes to the template in the Source Editor. NE+
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*/ z4 KKt&
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package com.tot.count; 30{WGc@l#
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/** -`,Fe3
* OPC8fX5.
* @author KN".0WU
*/ Bb.U4#
public class CountBean { h@fF`
private String countType; e#(X++G
int countId; BVu{To:g
/** Creates a new instance of CountData */ w]O,xO
public CountBean() {} n a+P|'6
public void setCountType(String countTypes){ Dr5AJ`y9A
this.countType=countTypes; >\[| c
} 2#R8}\
public void setCountId(int countIds){ m.Ki4NUm
this.countId=countIds; lQ#='Jqfp
} M=Y['wx
public String getCountType(){ Or:P*l
return countType; ,AwX7gx22
} x+EEMv3u:
public int getCountId(){ h_15 " rd
return countId; IGF25-7B
} f0+vk'Z
} Lmw4
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CountCache.java w+iIay
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/*
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* CountCache.java gjn1ha"h%.
* 1t}
* Created on 2007年1月1日, 下午5:01 "x
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* GrI<w.9X
* To change this template, choose Tools | Options and locate the template under UdcrX`^.
* the Source Creation and Management node. Right-click the template and choose gl 27&'?E*
* Open. You can then make changes to the template in the Source Editor. -l?\hmDl
*/ xc,Wm/[
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package com.tot.count; C/MQY:X4
import java.util.*; J=b'b%
/** R)6"P?h._4
* .+&M,%
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* @author yaPx=^&
*/ WJy\{YAG
public class CountCache { j[Gg[7q{y
public static LinkedList list=new LinkedList(); +aN"*//i
/** Creates a new instance of CountCache */ vQy+^deW
public CountCache() {} v(p<88.!m
public static void add(CountBean cb){ A~H@0>1
if(cb!=null){ }!N/?A5
list.add(cb); {Mc;B9W
} :Z+Jt=;
} >1$Vh=\OI
} 'cA(-ghY/E
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CountControl.java 1AQy8n*
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/* }WHq?
* CountThread.java iw{^nSD
* Bo8NY!
* Created on 2007年1月1日, 下午4:57 ef2)k4)"
* TT={>R[B
* To change this template, choose Tools | Options and locate the template under hG>kx8h
* the Source Creation and Management node. Right-click the template and choose 3
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* Open. You can then make changes to the template in the Source Editor. >fzFNcO*
*/ MqRJ:x
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package com.tot.count; }8'b}7!
import tot.db.DBUtils; 6[-[6%o#z
import java.sql.*; KPA.5,ai
/** %e(DPX
* qWD(rq+9
* @author O bc>f|l]
*/ hGRHuJ
public class CountControl{ q4Mv2SPT
private static long lastExecuteTime=0;//上次更新时间 d<[L^s9
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 f$qkb$?]}
/** Creates a new instance of CountThread */ 38GZ_z}r
public CountControl() {} s7,D}Zz
public synchronized void executeUpdate(){ ._q<~_~R
Connection conn=null; 0cq<!{d
PreparedStatement ps=null; &r2\P6J
try{ ZE9.r`
conn = DBUtils.getConnection(); "O~kIT?/v
conn.setAutoCommit(false); -t: U4r(
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); "[0.a\ d<
for(int i=0;i<CountCache.list.size();i++){ q@1xYz:J
CountBean cb=(CountBean)CountCache.list.getFirst(); <GLn!~Px@5
CountCache.list.removeFirst(); .-)kIFMi
ps.setInt(1, cb.getCountId()); AWd,qldv
ps.executeUpdate();⑴ nO#x"
//ps.addBatch();⑵ nPk&/H%5hn
} +'wO:E1( w
//int [] counts = ps.executeBatch();⑶ &Tg~A9y\
conn.commit(); AWi+xo|
}catch(Exception e){ D"exI]
e.printStackTrace(); 1u"#rC>7.4
} finally{ }b]eiPWN
try{ T3@34}*
if(ps!=null) { WEtPIHruyt
ps.clearParameters(); G&08Qb ,N
ps.close(); ZEso2|
ps=null; Hwcm t!y
} @2;cv?i)
}catch(SQLException e){} ]n3!%0]\
DBUtils.closeConnection(conn); 28vQ
} k U0.:Gcc
} qg:EN~E#
public long getLast(){ wo;OkJKF
return lastExecuteTime; r"|.`$:B
} C[5dhFZ
public void run(){ 0{
long now = System.currentTimeMillis(); 3-'3w ,
if ((now - lastExecuteTime) > executeSep) { Jhfw$ DF
//System.out.print("lastExecuteTime:"+lastExecuteTime); Ss_}@p ^
//System.out.print(" now:"+now+"\n"); (T%Ue2zlY
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); k5Su&e4]]
lastExecuteTime=now; h/6^>setz
executeUpdate();
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} s+(@UUl
else{ vM50H
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); [LO=k|&R
} i.\ e/9]f
} iB` EJftI!
} zrf
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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 _!_1=|[
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类写好了,下面是在JSP中如下调用。 $Ggnn#
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<% nLx|$=W
CountBean cb=new CountBean(); 6OoOkNWF
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); Z{gm4YV
CountCache.add(cb); ;#9ioGx
out.print(CountCache.list.size()+"<br>"); zQ#*O'-n
CountControl c=new CountControl(); I?^(j;QpS
c.run(); .h\Py[h<^
out.print(CountCache.list.size()+"<br>"); }kP<zvAaw
%>