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: j<'ftKk
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CountBean.java 6%it`A8}
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/* M0yv=g
* CountData.java w p\-LO~
* Qp7h|<
* Created on 2007年1月1日, 下午4:44 1J([*)
* LI*=T
* To change this template, choose Tools | Options and locate the template under \#4mPk_"
* the Source Creation and Management node. Right-click the template and choose _iu~vU)r
* Open. You can then make changes to the template in the Source Editor. F42<9)I
*/ CFC15/yU
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package com.tot.count; #N"m[$;QR
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/** A3)"+`&PUl
* x$;RfK2&p
* @author 4_kY^"*#"
*/ EHN(K-
public class CountBean { OClG dFJ|
private String countType; oqAO@<dL!
int countId; aVCPaYe^
/** Creates a new instance of CountData */ yIhPB8QL
public CountBean() {} aq)g&.dw?
public void setCountType(String countTypes){ DkX^b:D*f
this.countType=countTypes; ; [G:
} Q3Pu<j}Y
public void setCountId(int countIds){ URceq2_
this.countId=countIds; yDfH`]i)U
} nNq<x^@83
public String getCountType(){ D=Q.Q
return countType; D&i\dgbK
} FQJiLb._Z
public int getCountId(){ %N)B8A9kh
return countId; To}eJ$8*5
} /78]u^SW
} ((C|&$@M
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CountCache.java ?z`={oN
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/* !m^;wkrY
* CountCache.java Li]bU
* b"WF]x|^
* Created on 2007年1月1日, 下午5:01 VwpC UW
* n&Ckfo_D
* To change this template, choose Tools | Options and locate the template under f`:GjA,J$
* the Source Creation and Management node. Right-click the template and choose d7Vp^^}(
* Open. You can then make changes to the template in the Source Editor. U$mDAi$
*/ 1~t.2eU G
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package com.tot.count;
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import java.util.*; VcGl8~#9
/** >ei~:z]R
* gUNhN1=
* @author G &xtL
*/ Pr1qX5> =
public class CountCache { yI1:L
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public static LinkedList list=new LinkedList(); T?Kh'
/** Creates a new instance of CountCache */ t5%cpkgh4
public CountCache() {} g'KxjjYT,
public static void add(CountBean cb){ Mh*r)B~%[
if(cb!=null){ ||JUP}eP
list.add(cb); 4XNheP;b
} x(._?5
} w+/`l*
} KJRAW]?{
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CountControl.java 0S^&A?$=
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/* tBbOxM m0
* CountThread.java PQDLbSe)\
* +=jS!
* Created on 2007年1月1日, 下午4:57 ep=r7Mft
* :~ pGHl
* To change this template, choose Tools | Options and locate the template under n74\{`8]o
* the Source Creation and Management node. Right-click the template and choose y92R}e\M
* Open. You can then make changes to the template in the Source Editor. +9w[/n ^,G
*/ Iz1x| EQ
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package com.tot.count; iI{L>
import tot.db.DBUtils; <mQXS87
import java.sql.*; LP6p
/** l3sF/zkH
* SK
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* @author _8a;5hS
*/ qS#G7~ur>y
public class CountControl{ c`soVqT$?
private static long lastExecuteTime=0;//上次更新时间 '|DW#l\n
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 hE|P|0U,n
/** Creates a new instance of CountThread */ .Q%Hi7JMi
public CountControl() {} gom!dB0J
public synchronized void executeUpdate(){ X>8,C^~$1
Connection conn=null; =SXdO)%2
PreparedStatement ps=null; F%h3?"s
try{ M@R"-$Z
conn = DBUtils.getConnection(); G9f6'5 O
conn.setAutoCommit(false); eCYPd-d
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); Fp/{L
for(int i=0;i<CountCache.list.size();i++){ C3}:DIn"w
CountBean cb=(CountBean)CountCache.list.getFirst(); 3]l)uoNt/
CountCache.list.removeFirst(); ~ubvdQEW
ps.setInt(1, cb.getCountId()); [3jJQ3O,
ps.executeUpdate();⑴ F{0\a;U@^
//ps.addBatch();⑵ g}NO$?ndg
} %"0, o$
//int [] counts = ps.executeBatch();⑶ "E(i<
conn.commit(); o/w3b8
}catch(Exception e){ 6;Z-Y>\c
e.printStackTrace(); umIGI
} finally{ bZ\R0[0
try{ ]xQv\u
if(ps!=null) { dymq
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ps.clearParameters(); 3PE.7-HF
ps.close(); Ipk;Nq
ps=null; S MWXP
} @|\9<S
}catch(SQLException e){} R9U{r.AA
DBUtils.closeConnection(conn); 3>KEl^1DB
} )i~AXBt}
} iApq!u,
public long getLast(){ &Q3Fgj
return lastExecuteTime; lI<jYd
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} GGp.u@\r
public void run(){ uzBQK
long now = System.currentTimeMillis(); sp,-JZD
if ((now - lastExecuteTime) > executeSep) { Zz0bd473k?
//System.out.print("lastExecuteTime:"+lastExecuteTime); FJ_7<4ET
//System.out.print(" now:"+now+"\n"); <y@vv
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 1Cw]~jh
lastExecuteTime=now; Y;/@[AwF
executeUpdate(); aUaeK(x:H
} 6kYluV+j
else{ X`.##S KC
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); {y9G
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} z&6_}{2,]
} w:t~M[kTW
} $*ff]>#
//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 DZSS
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类写好了,下面是在JSP中如下调用。 !Y ,7%
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<% cUY-
CountBean cb=new CountBean(); iFd
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); { ADd[V
CountCache.add(cb); 3`bQ0-D;
out.print(CountCache.list.size()+"<br>"); ;P91'B~t
CountControl c=new CountControl(); {7o3wxsS
c.run(); 6KMO*v
out.print(CountCache.list.size()+"<br>"); -G(me"Cu
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