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: K9.Gjw
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CountBean.java <YtjE!2
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/* 122s7A
* CountData.java #AB5}rPEI
* ez ! W0
* Created on 2007年1月1日, 下午4:44 ^H7xFd|>
* Ef?hkq7X<
* To change this template, choose Tools | Options and locate the template under 7)Vbp--b#
* the Source Creation and Management node. Right-click the template and choose iF Mf[qBg
* Open. You can then make changes to the template in the Source Editor. nT}Wx/aT
*/ <G|i5/|7
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package com.tot.count; :fwt PvLo
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/** @M B)B5
* 4bp})>}jB
* @author '2i !RT-
*/ <qpzs@
public class CountBean { 9(q(;|;Hp
private String countType; @!'}=?`
int countId; 3 (\D.Z
/** Creates a new instance of CountData */ @y~kQ5k
public CountBean() {} 8
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public void setCountType(String countTypes){ '7PaJj=Nx
this.countType=countTypes; G" E_4YkJ
} s[y.gR.(
public void setCountId(int countIds){ !&hqj$>-}
this.countId=countIds;
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} mB"I(>q*M
public String getCountType(){ {ri={p]l
return countType; OR!W3
@
} ![_0GFbT
public int getCountId(){ +)WU:aKI
return countId; JffaT_"\
} {4,],0bjx/
} -,b+tC<V)0
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CountCache.java ;m#4Q6k)V?
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/* q)Nw$dW<
* CountCache.java b^C27s
* % g
* Created on 2007年1月1日, 下午5:01 .kg 3>*
* *j&)=8Y|
* To change this template, choose Tools | Options and locate the template under t1o
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* the Source Creation and Management node. Right-click the template and choose Z:7eroZP
* Open. You can then make changes to the template in the Source Editor. B+U:=591
*/ WEe7\bWF
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package com.tot.count; o.A:29KoU
import java.util.*; [bP^RY:
/** eBnx$
* tx>7?e8E
* @author E5)0YYjHZ
*/ <A8>To<
public class CountCache { 6V]m0{:E
public static LinkedList list=new LinkedList(); :,aY|2si
/** Creates a new instance of CountCache */ Sk>=C0f:
public CountCache() {} !pw)sO~
public static void add(CountBean cb){ t~j6w sx;
if(cb!=null){ \q1tT!]
list.add(cb); dB[4NT
} (~zu4^9w
} 2<I=xWwFA
} f%@~|:G:
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CountControl.java `}#rcDK
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/*
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* CountThread.java jL^@;"/XhC
* =3-?$
* Created on 2007年1月1日, 下午4:57 {<gv1Yht
* >x;\H(g
* To change this template, choose Tools | Options and locate the template under {@)ZXg
* the Source Creation and Management node. Right-click the template and choose 4 O8ct,Y
* Open. You can then make changes to the template in the Source Editor. $$NWN?H~
*/ O8$~dzf,2
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package com.tot.count; IoLi7NKw
import tot.db.DBUtils; SK'h!Ye5Z
import java.sql.*; "d$~}=a[
/** ;un@E:
* e!jy6t
* @author 7\2I>W
*/ )8W! |
public class CountControl{ h>\C2Q
private static long lastExecuteTime=0;//上次更新时间 P\ke%Jdpw?
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 /ki-Tha
/** Creates a new instance of CountThread */ XlU\D}zS
public CountControl() {} "Esl I
public synchronized void executeUpdate(){ FefroaJ:u
Connection conn=null; n>q!m@ }<
PreparedStatement ps=null; %T]^,y$n
try{ "UMaZgI
conn = DBUtils.getConnection(); [A84R04_%
conn.setAutoCommit(false); n>y,{"J{
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 37zBX~
for(int i=0;i<CountCache.list.size();i++){ M.mn9kw`
CountBean cb=(CountBean)CountCache.list.getFirst(); YJ6~P
CountCache.list.removeFirst(); T[|#DMg$F
ps.setInt(1, cb.getCountId()); I!Z`'1"
ps.executeUpdate();⑴ 3tTOs
//ps.addBatch();⑵ z:#]P0
} CLaQE{
//int [] counts = ps.executeBatch();⑶ .u&xo{$'dS
conn.commit(); S"h;u=5it
}catch(Exception e){ r$={_M$
e.printStackTrace();
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} finally{ e`qrafa
try{ V'XEz;Ze
if(ps!=null) { Qi`3$<W>
ps.clearParameters(); [Xu8~c X
ps.close(); <@.e.H
ps=null; eW(pP>@k,
} 5 qfvHQ ~M
}catch(SQLException e){} 6AAvsu:
DBUtils.closeConnection(conn); ;b0Q%TDh
} U~:H>
} k=mQG~
public long getLast(){ F0U %m
return lastExecuteTime; }MRgNr'k
} >6o <Q
public void run(){ %`&n ;K.c
long now = System.currentTimeMillis(); p<r<Y%
if ((now - lastExecuteTime) > executeSep) { 7_1 Iadb
//System.out.print("lastExecuteTime:"+lastExecuteTime); C{J5:ak
//System.out.print(" now:"+now+"\n"); LBy`N_@
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ZR}v_]l^
lastExecuteTime=now; eA!Z7 '
executeUpdate(); .A< HM}
} Og7yT{h_
else{ AhF@
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); <J;O$S
} 3$!QP
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} #Zm`*s`
} <=7nTcO~
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 TRi#
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类写好了,下面是在JSP中如下调用。 );.$`0
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<% JU>~[yAP
CountBean cb=new CountBean(); b\(f>g[
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); PuP"(
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CountCache.add(cb); {S=<(A@
out.print(CountCache.list.size()+"<br>"); uQO5GDuK>
CountControl c=new CountControl(); m0bxVV^DK!
c.run(); r*`e%`HU
out.print(CountCache.list.size()+"<br>"); @GKDSS4jv
%>