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: Q`= ,&;T>
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CountBean.java Zw@=WW[Q`p
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/* &Ul8h,qw
* CountData.java |azdFf6A:[
* faTp|T`nY
* Created on 2007年1月1日, 下午4:44 Lp1\vfU<+
* (AIgW
* To change this template, choose Tools | Options and locate the template under 8&q[jxI@8
* the Source Creation and Management node. Right-click the template and choose QVT|6znw
* Open. You can then make changes to the template in the Source Editor. Pi/V3D)B
*/ I='6>+P
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package com.tot.count; *3R3C+
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/** -d+o\qp"#
* Al}D~6MD
* @author 7cMHzhk^
*/ UiE 1TD{
public class CountBean { eVRPjVzQ'Q
private String countType; Y'&rSHI"
int countId; FTJvkcc?m
/** Creates a new instance of CountData */
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public CountBean() {} k`(Cwp{Oc
public void setCountType(String countTypes){ XbaUmCuh
this.countType=countTypes; IIh \d.o
} z%lLbKSe
public void setCountId(int countIds){ fUKi@*^ZUa
this.countId=countIds; T8t_+|(
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}
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public String getCountType(){ n=iL6Yu(
return countType; bmP2nD6
} -]~KQvIH!
public int getCountId(){ qGkD] L
return countId; )<K3Fz
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} Sv>bU4LHf
} ;N?raz2mEi
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CountCache.java lHI?GiB@
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/* crlCN
* CountCache.java 3uy^o
* Nc_Qd4<[@G
* Created on 2007年1月1日, 下午5:01 vxZ :l
* D:=Q)Uh0I
* To change this template, choose Tools | Options and locate the template under CFW#+U#U
* the Source Creation and Management node. Right-click the template and choose [AN= G!r
* Open. You can then make changes to the template in the Source Editor. (Kg( 6E,
*/ c`s ]ciC
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package com.tot.count; Aa!#=V1d
import java.util.*; 4S\S t<
/** 6}JW- sA
* =@*P})w5.
* @author DP6>fzsl
*/ "?Yf3G: \0
public class CountCache { Mh"vH0\Lj
public static LinkedList list=new LinkedList(); b{(= C
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/** Creates a new instance of CountCache */ Aq,&p,m03
public CountCache() {} ojbms>a
public static void add(CountBean cb){ |y DaFv
if(cb!=null){ #McX
list.add(cb); 20`QA
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} COFCa&m9c
} ^X|Bzz)
} EY}*}- 3
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CountControl.java FB }8
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/* fD~f_Wr
* CountThread.java Gq =i-I
* A&UGr971
* Created on 2007年1月1日, 下午4:57 v<:/u(i
* vC%Hc/&.}
* To change this template, choose Tools | Options and locate the template under %mNd9 ]<
* the Source Creation and Management node. Right-click the template and choose 8],tGMu
* Open. You can then make changes to the template in the Source Editor. RCY}JH>}
*/ .mvpFdn
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package com.tot.count; D[Kq`
import tot.db.DBUtils; 4=C7V,a
import java.sql.*; >vZ^D
/** AkA2/7<[
* &w{:
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* @author 1JY3c
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*/ f19'IH$n{
public class CountControl{ i _YJq;(
private static long lastExecuteTime=0;//上次更新时间 d6zfP1lQ
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 zc&i 4K
/** Creates a new instance of CountThread */ f<LRM
public CountControl() {} @!,W]?{
public synchronized void executeUpdate(){ ~pPj
Connection conn=null; 0/fA>%&
PreparedStatement ps=null; NflRNu:-
try{ c+.?+g
conn = DBUtils.getConnection(); JB9s#`
conn.setAutoCommit(false); W3]?>sLE*
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); O =\`q6l
for(int i=0;i<CountCache.list.size();i++){ { v#wU
CountBean cb=(CountBean)CountCache.list.getFirst(); v 0D@`C
CountCache.list.removeFirst(); ,`U'q|b
ps.setInt(1, cb.getCountId()); f;]C8/ W
ps.executeUpdate();⑴ }q=uI`
//ps.addBatch();⑵ g$^I/OK?
} N&]_U%#Q
//int [] counts = ps.executeBatch();⑶ 68nBc~iAm
conn.commit(); MOIMW+n
}catch(Exception e){ gF~#M1!!
e.printStackTrace(); p(pL"
} finally{ f6JC>Np
try{ Y%#r&de
if(ps!=null) { fB`7f
$[
ps.clearParameters(); +a74] H"
ps.close(); (T1d!v"~"
ps=null; gbjql+Mx+
} y /OPN<=*
}catch(SQLException e){} u8b^DB#+W
DBUtils.closeConnection(conn); cp L '
} {7+y56[yu
} \) vI-
public long getLast(){ 2M*84oh8P
return lastExecuteTime; uM@ve(8\
} mE"},ksg
public void run(){ BiD}C
long now = System.currentTimeMillis(); OG{vap)
if ((now - lastExecuteTime) > executeSep) { 2F|06E'
//System.out.print("lastExecuteTime:"+lastExecuteTime); '-vzQ d@y
//System.out.print(" now:"+now+"\n"); T )"Uq
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); TUM7(-,9
lastExecuteTime=now; 3#~w#Q0%
executeUpdate(); _>(qQ-Px
} &ngG_y8}&
else{ !R3ZyZcX
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); :y3e-lr
} A&7~]BR\
} faPgp
} OQ*rxLcA
//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 mH5[(?
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类写好了,下面是在JSP中如下调用。 ~v^I*/uY
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<% Ob
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CountBean cb=new CountBean(); *k<{ nj@y
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); |QxT"`rT
CountCache.add(cb); #*x8)6Ct
out.print(CountCache.list.size()+"<br>"); J6J|&Z~UT,
CountControl c=new CountControl(); 7$|L%Sk
c.run(); q+?>shqsZ
out.print(CountCache.list.size()+"<br>"); =`fz#Mfd
%>