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: ki?ETC
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CountBean.java {-l:F2i
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/* j/, I)Za
* CountData.java h|N!U/(U
* C zxF
* Created on 2007年1月1日, 下午4:44 "H|hN
* lNx:_g:SrZ
* To change this template, choose Tools | Options and locate the template under *n_7~ZX
* the Source Creation and Management node. Right-click the template and choose J0UF(
* Open. You can then make changes to the template in the Source Editor. O^r,H,3S
*/ j[|mC;y.
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package com.tot.count; /-Y.A<ieN8
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/** /3o@I5
* aA=7x&z@
* @author Gg3<
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*/ J_d!` Hhe
public class CountBean { 8B;HMD
private String countType; )|B3TjHC
int countId; kqZ+e/o>O9
/** Creates a new instance of CountData */ ~IQw?a.E
public CountBean() {} ZDr&Alp)o
public void setCountType(String countTypes){ K9c5HuGy
this.countType=countTypes; u&r+ylbsI
} 6tN!]
public void setCountId(int countIds){ QygbfW6u
this.countId=countIds; +K:hetv
} 'Omj-o'tn9
public String getCountType(){ ~#|Pe1Y
return countType; f5,!,]XO
} :,Mg1Zf
public int getCountId(){ dPmNX-'7
return countId; %<h+_(\h
} wqAj=1M\
} V%JG :'6L
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CountCache.java :\KJw
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/* `:kI@TPI_C
* CountCache.java HB9|AQ4K
* ~JTp8E9kw
* Created on 2007年1月1日, 下午5:01 l [
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* /EV _Y|(-
* To change this template, choose Tools | Options and locate the template under O_^;wey0}?
* the Source Creation and Management node. Right-click the template and choose frUO+
* Open. You can then make changes to the template in the Source Editor. nE=,=K~
*/ A;gU@8m
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package com.tot.count; aUbmEHFTV
import java.util.*; *V?p&/>MT
/** 1Ts$kdO
* \kG;T=H
* @author ?K=
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*/ %Mr^~7nN
public class CountCache { !@9G9<NK
public static LinkedList list=new LinkedList(); ,Kwtp)EX
/** Creates a new instance of CountCache */ 15CKcM6
public CountCache() {} @"L*!
public static void add(CountBean cb){ M`tNYs]V
if(cb!=null){ NH;.!xq:
list.add(cb); :7)lg iM2
} V2IurDE
} p>= b|Qy|
} X*e<g=
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CountControl.java 3oMhsQz~z
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/* hYSf;cG}A
* CountThread.java `l+
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* 3pjK`"Nmz\
* Created on 2007年1月1日, 下午4:57 %SJFuw"
* 1Y{pf]5Wx
* To change this template, choose Tools | Options and locate the template under abkt&981K+
* the Source Creation and Management node. Right-click the template and choose }S6"$R
* Open. You can then make changes to the template in the Source Editor. &z?:s
*/ _!E)a
/Bp5^(s
package com.tot.count; ^e(*{K;8
import tot.db.DBUtils; 5?XIp6%x
import java.sql.*; o>Q=V0?
/** OtZc;c
* i?B(I4a!G
* @author r"&VG2c0K
*/ % jSB9
public class CountControl{ UzT"Rb:e
private static long lastExecuteTime=0;//上次更新时间 DgODTxiX
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 N~+ e\K6
/** Creates a new instance of CountThread */ < m/@_"
public CountControl() {} 10{zF_9yx
public synchronized void executeUpdate(){ )=%TIkeF
Connection conn=null; ##BfI`FJ
PreparedStatement ps=null; _7b' i6-
try{ \&b1%Asyz
conn = DBUtils.getConnection(); tWaM+W
conn.setAutoCommit(false); UB,:won
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); a}[ 1*_G
for(int i=0;i<CountCache.list.size();i++){ @k3xk1*
CountBean cb=(CountBean)CountCache.list.getFirst(); ]h?p3T$h
CountCache.list.removeFirst(); N^%7
ps.setInt(1, cb.getCountId()); o+F<
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ps.executeUpdate();⑴ 5LzP0F
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//ps.addBatch();⑵ aM|;3j1p
} +\U#:gmw
//int [] counts = ps.executeBatch();⑶ Z!2%{HQ=q
conn.commit(); H&!?c5
}catch(Exception e){ =pd#U
e.printStackTrace(); giORc
} finally{ 0YO/G1O&
try{ Sd+bnq%
if(ps!=null) { ^]X\boWlI
ps.clearParameters(); ' ?uwUBi
ps.close();
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ps=null; |H
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} fzZ`O{$8
}catch(SQLException e){} D] +]Br8
DBUtils.closeConnection(conn); {8T/;K@
} Pd04
} jKr>Ig=$tA
public long getLast(){ Eal*){"<,?
return lastExecuteTime; cjwc:3
CM
} ,racmxnv
public void run(){
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long now = System.currentTimeMillis(); UZx8ozv'
if ((now - lastExecuteTime) > executeSep) { ,f}u|D 3@
//System.out.print("lastExecuteTime:"+lastExecuteTime); *u ]aWx
//System.out.print(" now:"+now+"\n"); >,a$)z
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); <g1=jG:7k
lastExecuteTime=now; &n~v;M
executeUpdate(); /&+*X)#v
} ;|pw;-
else{ U5ME`lN*`
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); vJ{aBx`VS
} h?P-
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} Y(B3M=j
} Sy"!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 c0QKx=
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类写好了,下面是在JSP中如下调用。 y&6 pc
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<% .O6(QI*
CountBean cb=new CountBean(); %/w%A:y#&
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); Ni>!b6Z`[
CountCache.add(cb); w@x||K= Z
out.print(CountCache.list.size()+"<br>"); v,d'SR.
CountControl c=new CountControl(); /wU4^8Hz
c.run(); M`p[ Zq
out.print(CountCache.list.size()+"<br>"); w\y)
%>