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: /dYv@OU?
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CountBean.java DD$>3`
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/* G@H!D[wd
* CountData.java "9s_[e
* V_SH90@)+
* Created on 2007年1月1日, 下午4:44 f zo'9
* h )
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* To change this template, choose Tools | Options and locate the template under (*$bTI/~
* the Source Creation and Management node. Right-click the template and choose jCJcVO>OZ
* Open. You can then make changes to the template in the Source Editor. DRQx5fgL
*/ Gc|)4c
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package com.tot.count; kCTf>sJe
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/** uMg\s\Z
* d5m-f/
* @author ,_3hbT8Q
*/ tz@MZs09
public class CountBean { !e|\1v'0
private String countType; !B3TLeh
int countId; ls@]%pz.1d
/** Creates a new instance of CountData */ R
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public CountBean() {} Q|AZv>'!
public void setCountType(String countTypes){
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this.countType=countTypes; >u$8Z
} SQ>i:D;
public void setCountId(int countIds){ SL4?E<Jb
this.countId=countIds; >Wr%usNxc
} d<a|dwAeh
public String getCountType(){ 1Nt
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return countType; K29/7A/
} EG>?>K_D
public int getCountId(){ Xi&J%N'
return countId; W*C~Xba<
} 0\%g@j-aD
} &-ropY
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CountCache.java lxhb)]c
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/* /d3Jd.l!
* CountCache.java MoIh=rw
* *1dDs^D#|
* Created on 2007年1月1日, 下午5:01 ~ skp}g]
* P"vrYom
* To change this template, choose Tools | Options and locate the template under 3xChik{
* the Source Creation and Management node. Right-click the template and choose =j,WQ66r3
* Open. You can then make changes to the template in the Source Editor. glMHT,
*/ 7QsD"rL
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package com.tot.count; *|AQV:
import java.util.*;
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/** V"4Z9Qg}
* !a@)6or
* @author w"^h<]b
*/ W'[V$*
public class CountCache { 'h*jL@%TT
public static LinkedList list=new LinkedList(); p>B2bv+L
/** Creates a new instance of CountCache */ XNJ4T]><
public CountCache() {} t7+A!7b{
public static void add(CountBean cb){ s6bsVAO>
if(cb!=null){ bHwEd%f
list.add(cb); I^?tF'E
} kU<t~+
} l[}4
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} T D_@0Rd
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CountControl.java eM5?fE&!&
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/* [oLV,O|s|j
* CountThread.java ^ po@U"
* gF)9a_R%p
* Created on 2007年1月1日, 下午4:57 [qYr~:` -[
* 5> x_G#W
* To change this template, choose Tools | Options and locate the template under h|qJ{tUWc$
* the Source Creation and Management node. Right-click the template and choose vQMBJ&
* Open. You can then make changes to the template in the Source Editor. .hl_zc#
*/ bNea5u##
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package com.tot.count; 3A#Tn7
import tot.db.DBUtils; GShxPH{_j
import java.sql.*; z5>I9R^q;
/** H71sxek3
* K;?D^n.
* @author P-@MLIC{
*/ !/zRw-q3B
public class CountControl{ cl4E6\?z
private static long lastExecuteTime=0;//上次更新时间 (eN7s_
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 j6rN t|
/** Creates a new instance of CountThread */ ";K w?
public CountControl() {} +hxG!o?O
public synchronized void executeUpdate(){ ZitM<Qi&y
Connection conn=null; d#ir=+o{h
PreparedStatement ps=null; !J`lA
try{ ZaFt4#
conn = DBUtils.getConnection(); 2B,O/3y
conn.setAutoCommit(false); Ed9Uw7
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); /A=w`[<
for(int i=0;i<CountCache.list.size();i++){ 6%v9o?:~l
CountBean cb=(CountBean)CountCache.list.getFirst(); -=ZL(r
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CountCache.list.removeFirst(); JB_fS/I
ps.setInt(1, cb.getCountId()); sXIYl% d
ps.executeUpdate();⑴ R?{+&r.X
//ps.addBatch();⑵ F/>_PH57
} -pC8 L<
//int [] counts = ps.executeBatch();⑶ h@:K=ggK
conn.commit(); ?"B]"%M&
}catch(Exception e){ ,lyW'<~gA
e.printStackTrace(); :D.0\.p
} finally{ z|l*5@p
try{ ~Z\:Nx
if(ps!=null) { U ZM #O
ps.clearParameters(); 22\!Z2@T/
ps.close(); EYAaK^ &
ps=null; kBu{ bxL
} oaoTd$/5
}catch(SQLException e){} /R)wM#&
DBUtils.closeConnection(conn); >[}oH2oi
} YDt+1Kw}D
} y>^a~}Zq
public long getLast(){ jwZ,_CK
return lastExecuteTime; 0I&k_7_
} OmYVJt_
public void run(){ V2MOD{Maat
long now = System.currentTimeMillis(); W'lqNOX[v
if ((now - lastExecuteTime) > executeSep) { 0'QWa{dS\
//System.out.print("lastExecuteTime:"+lastExecuteTime); P15
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//System.out.print(" now:"+now+"\n"); CD|[PkjW
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); }r:o8+4
lastExecuteTime=now; T<AT&4
executeUpdate(); 4fEDg{T
} !IxO''4
else{ S{@}ECla
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); zkQ[<
} C*7/iRe
} {z#2gc'Q
} GIC1]y-'
//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 "}4%v Zz
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类写好了,下面是在JSP中如下调用。 i|YS>Pw~j
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<% +.G"ool
CountBean cb=new CountBean(); / HTY>b
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); VtreOJ+
CountCache.add(cb); #(8|9
out.print(CountCache.list.size()+"<br>"); z6>@9+V-&
CountControl c=new CountControl(); PnlI {d
c.run(); d=!:UB
out.print(CountCache.list.size()+"<br>"); Cy/&KWLenf
%>