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: =;/4j'1}9
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CountBean.java \1[I(u
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/* :A,V<Es}I"
* CountData.java 64^dy V,;
* J2`b:%[
* Created on 2007年1月1日, 下午4:44 tZ]|3wp
* *JX)q
* To change this template, choose Tools | Options and locate the template under ~R]E=/ m|
* the Source Creation and Management node. Right-click the template and choose {Tp0#fi
* Open. You can then make changes to the template in the Source Editor. p0xd
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*/ kN4nRW9z
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package com.tot.count; 7RmL#f`
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/** +b.qzgH>r
* VJX{2$L
* @author }*~EA=YN;
*/ 7 N?x29
public class CountBean { 5O
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private String countType; 4-4lh
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int countId; \]U@=w
/** Creates a new instance of CountData */ \*H/YByTb
public CountBean() {} dF{3~0+,
public void setCountType(String countTypes){ HM])m>KeT
this.countType=countTypes; mAFqA
} ,uD F#xjl,
public void setCountId(int countIds){ 2roPZj
this.countId=countIds; x+vNA J
} h94SLj]
public String getCountType(){ ~ySmN}3~'
return countType; aXyu%<@k
} EOrWax@k$}
public int getCountId(){ ObIi$uJX
return countId; TR,,=3n
} J_s?e#s
} GdavCwJ
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CountCache.java .*>LD
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/* N:!XtYA<
* CountCache.java BJk:h-m [
* Jp.Sow
* Created on 2007年1月1日, 下午5:01 jMUE&/k
* PNXZ 3:W
* To change this template, choose Tools | Options and locate the template under J.:"yK""
* the Source Creation and Management node. Right-click the template and choose >\K<q>*
* Open. You can then make changes to the template in the Source Editor. /d5_-AB(v
*/ a\\B88iRRZ
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package com.tot.count; 5+GW%U/
import java.util.*; h)q:nlKUW
/** !W/O g 5n
* -9/YS
* @author 6g!#"=ls;
*/ R:B-4
public class CountCache { t'4hWNR'
public static LinkedList list=new LinkedList(); 8Uvf9,I'
/** Creates a new instance of CountCache */ ,JT|E~P?8
public CountCache() {} k+44ud.j
public static void add(CountBean cb){ ={b/s31H:
if(cb!=null){ y-}lz#N
list.add(cb); 2GcQh]ohc
} ]Ole#Lz}Q
} /`0*!sN*5
} a=k+:=%y
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CountControl.java a=gTGG"9
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/* 0G9@A8LU
* CountThread.java Giz9jzF\
* *#Hi W)
* Created on 2007年1月1日, 下午4:57 fyx-VXu
* TQ" [2cY
* To change this template, choose Tools | Options and locate the template under Eszwg
* the Source Creation and Management node. Right-click the template and choose [9a0J):w{
* Open. You can then make changes to the template in the Source Editor. bOux8OHt*
*/ oo3ZYA
$} l0Nh'Eu
package com.tot.count; j DcE_55o
import tot.db.DBUtils; b,7:=-D
import java.sql.*; N{iBVl
/** y<k-dbr
* ('W#r"
* @author |A7Yv
*/ C;wN>HE
public class CountControl{ S
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private static long lastExecuteTime=0;//上次更新时间 IoJkM-^H&)
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 'Y6{89 y
/** Creates a new instance of CountThread */ W<yh{u&,
public CountControl() {} Q5r cPU>A
public synchronized void executeUpdate(){ W!I"rdo;V
Connection conn=null; TxwZA
PreparedStatement ps=null; P f6rr9
try{ )qD%5} t
conn = DBUtils.getConnection(); 5bv(J
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conn.setAutoCommit(false); H0
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ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); gnNMuqt
for(int i=0;i<CountCache.list.size();i++){ V8NNIS
CountBean cb=(CountBean)CountCache.list.getFirst(); ;f[Ki$7
CountCache.list.removeFirst(); 6*kY7
ps.setInt(1, cb.getCountId()); 0 '~Jr\4
ps.executeUpdate();⑴ 6=90 wu3
//ps.addBatch();⑵ ?;+=bKw0
} sL~TV([6/
//int [] counts = ps.executeBatch();⑶ Hm`9M.5b
conn.commit(); oj$D3
}catch(Exception e){ /`D]m?
e.printStackTrace(); c>!>D7:7
} finally{ i+Px &9o<9
try{ !zvKl;yT
if(ps!=null) { C#p$YQf
ps.clearParameters(); N+b"LZc
ps.close(); v/8K?$"q
ps=null; tn6\0_5n
} kxhvy,t
}catch(SQLException e){} "X>Z!>
DBUtils.closeConnection(conn); 0+;.T1?
} %D\TLY
} /Y:_qsO1
public long getLast(){ B y6:
return lastExecuteTime; B~lrd#qC
} _,NL;66=[
public void run(){ er,R}v
long now = System.currentTimeMillis(); "Hg.pDNZ
if ((now - lastExecuteTime) > executeSep) { 7w|W\J^7r
//System.out.print("lastExecuteTime:"+lastExecuteTime); Bb]pUb
//System.out.print(" now:"+now+"\n"); {]]nQ
// System.out.print(" sep="+(now - lastExecuteTime)+"\n");
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lastExecuteTime=now; @?3u|m |Z
executeUpdate(); :"3WCB
} %@G<B
else{ *@dRL3c^=
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 6fY(u7m|p
} hqFK2
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} g*b%
} T5-50nU,~
//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 C
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aQMET~A:
类写好了,下面是在JSP中如下调用。 X/];*='Q
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<% niFX8%<hP
CountBean cb=new CountBean(); UALwr>+VJ
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ^lB1- ;ng
CountCache.add(cb); (".`#909
out.print(CountCache.list.size()+"<br>"); `;*Wt9
CountControl c=new CountControl(); tKo^A:M
c.run(); @GBS-iT3
out.print(CountCache.list.size()+"<br>"); C"<l}
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