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: XCQPVSh
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CountBean.java <Z\j#p:
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/* XI58Cy*!
* CountData.java =E4~/F}9/T
* b{hdEb
* Created on 2007年1月1日, 下午4:44 i@hW" [A
* C{P:1ELYXH
* To change this template, choose Tools | Options and locate the template under >q)VHV9P
* the Source Creation and Management node. Right-click the template and choose p28=l5y+
* Open. You can then make changes to the template in the Source Editor. g"Gj8QLDz
*/
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package com.tot.count; D./3,z
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/** +a}>cAj*
* DS6g_SS3
* @author Onj)AJ9M0r
*/ mUjM5ceAXO
public class CountBean { V[baGNe
private String countType; =Z}=n S?4
int countId; +tvWp>T+
/** Creates a new instance of CountData */ =X}s^KbI{
public CountBean() {} zTS#o#`!\
public void setCountType(String countTypes){ 6`U]%qx_I
this.countType=countTypes; vDp|9VY?
} "?#O*x
public void setCountId(int countIds){ `/L D:R
this.countId=countIds; Y<9]7R(\;
} UZb!tO2
public String getCountType(){ d0 qc%.s
return countType; ^A' Bghy
} YB3?Ftgw
public int getCountId(){ _omz74
return countId; JWo).
} \2NT7^H#
} P*.0kR1n
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CountCache.java 8$C?j\J|*
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/* 9 7Mi{Zz
* CountCache.java -VO* P
* 9 `z^'k&
* Created on 2007年1月1日, 下午5:01 &24$*Oe
* j]bNOC2.L
* To change this template, choose Tools | Options and locate the template under ;Br
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* the Source Creation and Management node. Right-click the template and choose .l}oxWWoS
* Open. You can then make changes to the template in the Source Editor. ~Op~~
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*/ |]'0z0>
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package com.tot.count; >^ijj`{d
import java.util.*; Yi+$g
/** z`KP
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* &n-)Alx
* @author e<1)KqG
*/
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public class CountCache { -/3D0`R
public static LinkedList list=new LinkedList(); CwQRHi
/** Creates a new instance of CountCache */ _8'z"wF
public CountCache() {} 3KN>t)A#
public static void add(CountBean cb){ g]Fm%iy
if(cb!=null){ 8KyF0r?
list.add(cb); 5;_&C=[
} !R@s+5P)U
} 2JX@#vQ4
} E
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CountControl.java 4NxI:d$&*
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/* *e}1KcJ
* CountThread.java u[~= a5:4
* jpRC6b?
* Created on 2007年1月1日, 下午4:57 AxZaV;%*
* 3}ATt".
* To change this template, choose Tools | Options and locate the template under _5&LV2
* the Source Creation and Management node. Right-click the template and choose CGY,I
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* Open. You can then make changes to the template in the Source Editor. UcxMA%Pw7$
*/ >nOzz0,
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package com.tot.count; hR(p{$-T
import tot.db.DBUtils; unN=yeut
import java.sql.*; .Mu]uQUF
/** F=l. 2t*9
* 32Jl|@8,g
* @author S1G3xY$0
*/ mj_V6`m4
public class CountControl{ 6V^KOG
private static long lastExecuteTime=0;//上次更新时间 c!HmZ]/
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 mH)th7
/** Creates a new instance of CountThread */ !y syb
public CountControl() {} {H[3[
public synchronized void executeUpdate(){ WuUT>omH
Connection conn=null; sad[(|
PreparedStatement ps=null; qS}pv
try{ )3A%Un#B
conn = DBUtils.getConnection(); -VP da @@w
conn.setAutoCommit(false); Z&j?@k,k
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ; 6*Ag#Z
for(int i=0;i<CountCache.list.size();i++){ CyEEE2cV
CountBean cb=(CountBean)CountCache.list.getFirst(); $3D#U^7i
CountCache.list.removeFirst(); Bn?MlG;aA
ps.setInt(1, cb.getCountId()); AB")aX2%E
ps.executeUpdate();⑴ SlojB ^%
//ps.addBatch();⑵ V^ 5Z9!
} =V*4&OU
//int [] counts = ps.executeBatch();⑶ R'1L%srTM+
conn.commit(); XX|wle1Kg
}catch(Exception e){ F-I\x
e.printStackTrace(); vg ^&j0
} finally{ QLum=YB
try{ n9x&Ws;
if(ps!=null) { ! tPHT
ps.clearParameters(); o dTg.m
ps.close(); \r7gubD
ps=null; bf&k:.v'8
} -e(,>9Q
}catch(SQLException e){} \jGvom.
DBUtils.closeConnection(conn); !|`vW{v
} CKgbb4;<m[
} SF?s^
public long getLast(){ 3&ES?MyB#
return lastExecuteTime; IQA<xqX
} *, RxOz2=
public void run(){ **L3T3$)
long now = System.currentTimeMillis(); Imm|5-qJ
if ((now - lastExecuteTime) > executeSep) { [[8.Xb
//System.out.print("lastExecuteTime:"+lastExecuteTime); sksop4gu5
//System.out.print(" now:"+now+"\n"); elzKtVw
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 2-!n+#Cdf
lastExecuteTime=now; 2B=''W
executeUpdate(); <rAk"R^
} qs'ggF1
else{ b"QeCw#v`>
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ]53'\TH
} 5|Or,8r(C
} g7),si*
} 6K
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//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 \~ql_X;3
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类写好了,下面是在JSP中如下调用。 .e8S^lSl
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<% P<GHX~nB
CountBean cb=new CountBean(); SP
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); wM#BQe3t#
CountCache.add(cb); X=d;WT4,,
out.print(CountCache.list.size()+"<br>"); <<:a>)6\
CountControl c=new CountControl(); 0nOp'Ky\k
c.run(); =gb(<`{>
out.print(CountCache.list.size()+"<br>"); u{"@
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