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: B`?}jJa9*
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CountBean.java /+ Q3JS(
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/* $BUm,
* CountData.java SKeX~uLz
* nC(<eL
* Created on 2007年1月1日, 下午4:44 lNba[;_
* ?{rpzrc!*
* To change this template, choose Tools | Options and locate the template under z6x`O-\
* the Source Creation and Management node. Right-click the template and choose "'v^X!"
* Open. You can then make changes to the template in the Source Editor. dBNx2T}_0
*/ :hFKmoy#
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package com.tot.count; Z,1b$:+
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/** 6'45c1e
* 0AD8X+M{P
* @author (Qf. S{;
*/ |*n
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public class CountBean { }BI|M_q.1~
private String countType; CRs@x` 5ue
int countId; W*r1Sy
/** Creates a new instance of CountData */ 9>9,
public CountBean() {} /X;/}fk
public void setCountType(String countTypes){ P"%f8C~r
this.countType=countTypes; M2pFXU?]
} N~~
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public void setCountId(int countIds){ kJK*wq]U6
this.countId=countIds; nZ %%{#T7
} _"[Ls?tRX
public String getCountType(){ ve^gzE$<I
return countType; ],s{%a5wC
} \>[k0<
public int getCountId(){ u~7fK
return countId; y}1Pc*
} 6uIgyO*;k
} aM+Am,n`@
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CountCache.java Vw]!Kb7tA
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/* ==AmL]*
* CountCache.java \03ZE^H
* !<>*|a
* Created on 2007年1月1日, 下午5:01 |]5`T9K@b#
* h"7~`!"~
* To change this template, choose Tools | Options and locate the template under {mUt|m7!
* the Source Creation and Management node. Right-click the template and choose 0<93i
* Open. You can then make changes to the template in the Source Editor. 8SA"
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*/ 6aLRnH"Ud
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package com.tot.count; 2Z>8ROv^X
import java.util.*; <nTZs`$LwL
/** Z/czAr@4
* \q\"=
* @author &0i$Y\g
*/ }bSDhMV;
public class CountCache { QBh*x/J
public static LinkedList list=new LinkedList(); ""A6n{4
/** Creates a new instance of CountCache */ /DjsnU~3
public CountCache() {} SlG^ H
public static void add(CountBean cb){ 3N5@<:2`
if(cb!=null){ />N# PF
list.add(cb); =R<92v
} XFYa+]B2q
} 1R;@v3
} 5mS/,fs@
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CountControl.java xS>vmnW
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/* W*%(J$E
* CountThread.java Xmi~fie
* S'\e"w
* Created on 2007年1月1日, 下午4:57 /EG'I{oC
* Kv2S&P|jXM
* To change this template, choose Tools | Options and locate the template under #uF`|M$u
* the Source Creation and Management node. Right-click the template and choose ?4oP=.
* Open. You can then make changes to the template in the Source Editor. P*H0Hwn;
*/ )E}@h%d
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package com.tot.count; Bgn%d4W;G
import tot.db.DBUtils; a#k7 aOT0
import java.sql.*; l4dG=x}M]
/** <nb%$2r1
* @%G?Nht]o
* @author hNhEA $X5
*/ Xhq6l3 M
public class CountControl{ x NjQ"'i8
private static long lastExecuteTime=0;//上次更新时间 ec`re+1r
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 YCQ$X
/** Creates a new instance of CountThread */ -cijLlz%+
public CountControl() {} ]<C]`W2{
public synchronized void executeUpdate(){ .6T0d
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Connection conn=null; s2<[@@@q
PreparedStatement ps=null; Uqb]&2
try{ E3l*_b0
conn = DBUtils.getConnection(); :o .+<_&
conn.setAutoCommit(false); JSi0-S[Y{
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); s5rD+g]E`
for(int i=0;i<CountCache.list.size();i++){ |35OA/O?X
CountBean cb=(CountBean)CountCache.list.getFirst(); 8Y.9%@
CountCache.list.removeFirst(); "TJ*mN.i{}
ps.setInt(1, cb.getCountId()); dJ
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ps.executeUpdate();⑴ B~7!v${
//ps.addBatch();⑵ 7KX27.~F
} R"9wVM;*c
//int [] counts = ps.executeBatch();⑶ fggs
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conn.commit(); kaXq.
}catch(Exception e){ DJ@n$G`^^
e.printStackTrace(); Y#XRn_2D
} finally{ /KX+'@
try{ 5K 2K'ZkI
if(ps!=null) { Hcwfe=K&/
ps.clearParameters(); "I)zi]vk
ps.close(); }ePl&-9T
ps=null; fO&`A:JY
} ?KOw~-u
}catch(SQLException e){} bY=[ USgps
DBUtils.closeConnection(conn); QcW8A ,\q
} vM6W64S
} nAEyL+6U
public long getLast(){ [GI~ &
return lastExecuteTime; m|B=
} .WqqP
public void run(){ >#x[qX
long now = System.currentTimeMillis(); %z-*C'j5H
if ((now - lastExecuteTime) > executeSep) { 5C9b*]-#
//System.out.print("lastExecuteTime:"+lastExecuteTime); 26rg-?;V^
//System.out.print(" now:"+now+"\n"); (+epRC
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); H{vKk
lastExecuteTime=now; 1wKXOy=v0
executeUpdate(); nYjrEy)Q
} ,
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else{ ]*\MIz{56'
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); z6C(?R
} P,{Q k~iu
} 3X`9&0:j%
} eMC^ORdY
//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 #@$80eFq
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类写好了,下面是在JSP中如下调用。 w3(|A> s3
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<% vTO9XHc E
CountBean cb=new CountBean(); 4SJ aAeIZ
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); {,Q )D$i
CountCache.add(cb); k.ou$mIY
out.print(CountCache.list.size()+"<br>"); Ig`q[o
CountControl c=new CountControl(); q`'f
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c.run(); \Y)HSJR;e
out.print(CountCache.list.size()+"<br>"); h#hr'3bI1
%>