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: hs?sGr
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CountBean.java !>>f(t4
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/* Dgx8\~(E'
* CountData.java J]q%gcM
* 1*dRK6
* Created on 2007年1月1日, 下午4:44 7{xh8#m
* k<cgO[m
* To change this template, choose Tools | Options and locate the template under L*Me."*
* the Source Creation and Management node. Right-click the template and choose /__PSK
* Open. You can then make changes to the template in the Source Editor. ^k
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*/ aM{xdTYaU
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package com.tot.count; WyZL9K{?
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/** "3<da* D1
* Zr-U&9.`
* @author JR@.R
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*/ j~FD{%4N
public class CountBean { STglw-TC\
private String countType; #Jna6
int countId; HmZ{L +"
/** Creates a new instance of CountData */ uio@r^Xz
public CountBean() {} KL ?@@7
public void setCountType(String countTypes){ @]![o %
this.countType=countTypes; bcAvM;
} \'M3|w`f
public void setCountId(int countIds){ ~u.T- 0F
this.countId=countIds; 11,!XD*"
} efD)S92
public String getCountType(){ %%Qo2^-
return countType; 5l,ZoB8
} Fh*j#*oe
public int getCountId(){ wQ%mN[
return countId; [|lB5gi4t!
} d oB
} 4&HXkRs:
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CountCache.java m~>Y{F2
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/* _$p$")
* CountCache.java 3 ( ]M{4j
* 7c;9$j
* Created on 2007年1月1日, 下午5:01 OKHX)"j\\
* ^::EikpF%
* To change this template, choose Tools | Options and locate the template under P1 zdK0TM
* the Source Creation and Management node. Right-click the template and choose ?\#N9+{W
* Open. You can then make changes to the template in the Source Editor. <BW[1h1k5_
*/ ncSFj.}w]
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package com.tot.count; 7y`}PMn
import java.util.*; 9<vWcq*4
/** 1&/FG(*/
* 8k^|G
* @author XK"-'
*/ 6O@J7P
public class CountCache { kEO7PK/
public static LinkedList list=new LinkedList(); 0[F:'_
/** Creates a new instance of CountCache */ fS:1^A2,
public CountCache() {} @m?QR(LJ
public static void add(CountBean cb){ !I\!;b
if(cb!=null){ Y $u9%0q|?
list.add(cb); k6kM'e3V
} \3Q&~j
} h!#:$|Q
} J|3E- p\o
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CountControl.java i%{3W:!4t
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/* UYA_jpI P
* CountThread.java @VN&t:/ l
* @Eb2k!T
* Created on 2007年1月1日, 下午4:57 ~Xlrvb}LP
* bT6sb#"W
* To change this template, choose Tools | Options and locate the template under )XfzLF7
* the Source Creation and Management node. Right-click the template and choose NjE</Empb%
* Open. You can then make changes to the template in the Source Editor. v?c 0[+?
*/ g}f9dB,F
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package com.tot.count; {}o>{&X
import tot.db.DBUtils; W[[bV
import java.sql.*; >3gi yeJ
/** GdVhK:<>
* j,d*?'X
* @author X1tXqHJF}
*/ t |W)
public class CountControl{ -B$~`2-
private static long lastExecuteTime=0;//上次更新时间 f1PN|
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 E`j-6:
/** Creates a new instance of CountThread */ i-U4RZE
public CountControl() {} za'6Y*CGgX
public synchronized void executeUpdate(){ hCYQGx0
Connection conn=null; E(Rh#+]Y5
PreparedStatement ps=null; =&dW(uyzY
try{ +Ug/rtK4
conn = DBUtils.getConnection(); Kd3?I5t
conn.setAutoCommit(false); 0Y]0!}
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); B$ KwkhMe
for(int i=0;i<CountCache.list.size();i++){ ~dHM4lGY
CountBean cb=(CountBean)CountCache.list.getFirst(); |BZDhd9<{
CountCache.list.removeFirst(); WS2osBc
ps.setInt(1, cb.getCountId()); \tyg(srw0
ps.executeUpdate();⑴
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//ps.addBatch();⑵ O8U<{jgAG
} !TAp+b
//int [] counts = ps.executeBatch();⑶ as+GbstN
conn.commit(); $3X-rjQtW
}catch(Exception e){ /Jf~25F
e.printStackTrace(); ,&HR(jTo
} finally{ OOBhbpg!D
try{ Zc"B0_&?:7
if(ps!=null) { Q/I)V2a1i
ps.clearParameters(); >\<*4J$PZ
ps.close(); }]UB;id'
ps=null; :
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} OndhLLz
}catch(SQLException e){} `N/RHb%
DBUtils.closeConnection(conn); sP'0Sl~NU
} 1\L[i];L8
} (x;g/!:
public long getLast(){ mgZf3?,)
return lastExecuteTime; 1x~U*vbhQ
} `A/j1UWJ
public void run(){ wzjU,Mwe
long now = System.currentTimeMillis(); /cFzotr"9
if ((now - lastExecuteTime) > executeSep) { Fk=}iB#(
//System.out.print("lastExecuteTime:"+lastExecuteTime); Hqz?E@bc@
//System.out.print(" now:"+now+"\n"); O)R(==P26P
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); rC[6lIP
lastExecuteTime=now; B6}FIg)
executeUpdate(); Dbx~n#n G
} <uP^-bv;(
else{ 5wC* ?>/
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ]>i~6!@
} lo&#(L+2
} W&"|}Pi/
} $mA5@O~C5\
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 IB9%QW"0
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类写好了,下面是在JSP中如下调用。 P5QQpY{<I
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<% Cup@TET35
CountBean cb=new CountBean(); t>UkE9=3\
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); tGcya0RL
CountCache.add(cb); ! o,5h|\
out.print(CountCache.list.size()+"<br>"); ]r]k-GZ$
CountControl c=new CountControl(); S\NL+V?7h
c.run(); e yw'7
out.print(CountCache.list.size()+"<br>"); d6 _C"r
%>