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: Km#pX1]>e
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CountBean.java EW<kI+0D
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/* l?8M
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* CountData.java 5J2=`=FK
* L<V3KS2y
* Created on 2007年1月1日, 下午4:44 +7V{ABfGl
* "O[j!fG8,
* To change this template, choose Tools | Options and locate the template under `J0i.0p
* the Source Creation and Management node. Right-click the template and choose S4^N^lQ]
* Open. You can then make changes to the template in the Source Editor. D${={x
*/ 5O/i3m26
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package com.tot.count; 1oLv.L
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/** SOZPZUUEJ
* %dST6$Z
* @author *?ITns W<
*/ (ll*OVL
public class CountBean { iRV~Il#~!
private String countType; X-LA}YH=tS
int countId; 8.J(r(;>
/** Creates a new instance of CountData */ P>ceeoYQuA
public CountBean() {} H*^\h?s
public void setCountType(String countTypes){ 4+;$7"fJ
this.countType=countTypes; :O<bA&:d
} x%+{VStA
public void setCountId(int countIds){ (-77[+2
this.countId=countIds; Ny- [9S-<
} +!IQj0&'Y3
public String getCountType(){ @Ky> 9m{
return countType; WE6a'
} B/JO~;{
public int getCountId(){ >LC<O.
return countId; xo}b=
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} TjMe?p
} h%; e0Xz|
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CountCache.java '_\;jFAM
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/* l>gI&1)%
* CountCache.java xT&(n/
* ]uj=:@
* Created on 2007年1月1日, 下午5:01 &3F}6W6A
* =L|tp%!
* To change this template, choose Tools | Options and locate the template under J_;N:7'p
* the Source Creation and Management node. Right-click the template and choose 9^"b*&>P
* Open. You can then make changes to the template in the Source Editor. g"s$}5{8:
*/ VV4Gjc
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package com.tot.count; /MMd`VrC2
import java.util.*; | Xi%
/** 5!YA o\S
* %J:SO_6
* @author gWABY%!}
*/ v~3B:k:?l
public class CountCache { \<Sv3xy&O
public static LinkedList list=new LinkedList(); YJg,B\z}
/** Creates a new instance of CountCache */ p.I.iAk%G^
public CountCache() {} 7(M(7}EKA
public static void add(CountBean cb){ H1GRMDNXOA
if(cb!=null){ Jj~EiA
list.add(cb); T9)nQ[
} vb 1@yQ
} Z=B_Ty
} a,F&`Wg
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CountControl.java ]<(]u#g_d
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/* 2sNK
* CountThread.java :@W.K5
* NNhL*C[_7
* Created on 2007年1月1日, 下午4:57 Xs&TJ8a
* D jk C
* To change this template, choose Tools | Options and locate the template under 09A
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* the Source Creation and Management node. Right-click the template and choose F' U 50usV
* Open. You can then make changes to the template in the Source Editor. c4&' D;=
*/ 73{'kK
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package com.tot.count; `Y-|H;z
import tot.db.DBUtils; $aHAv/&(5
import java.sql.*; MMB@.W
/** W$U0[^1
* ;.xoN|Per
* @author J q{7R
*/ +_XmlX A3Z
public class CountControl{ 43?^7_l-
private static long lastExecuteTime=0;//上次更新时间 u2oKH{/z
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ikWtC]y
/** Creates a new instance of CountThread */ DeR='7n
public CountControl() {} PH"hn]
public synchronized void executeUpdate(){ (~zd6C1.
Connection conn=null; K{n{KB&_&
PreparedStatement ps=null; m9U"[Huv1E
try{ x21dku<6K[
conn = DBUtils.getConnection(); p!]6ll^
conn.setAutoCommit(false); ~~/xRs
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); QL6C,#6
for(int i=0;i<CountCache.list.size();i++){ Kp+CH7I*
CountBean cb=(CountBean)CountCache.list.getFirst(); Rqwzh@}
CountCache.list.removeFirst(); ,q(&)L$S
ps.setInt(1, cb.getCountId()); bjAnaya
ps.executeUpdate();⑴ ThPE
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//ps.addBatch();⑵ >!_Xgw
} < >UPD02
//int [] counts = ps.executeBatch();⑶
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conn.commit(); I`z@2Z+pJ
}catch(Exception e){ JS}{ %(B
e.printStackTrace(); *'ZB*>
} finally{ >~`C-K#
try{ !`!| Zw
if(ps!=null) { ~Lc066bLeq
ps.clearParameters(); Y+K|1r
ps.close(); XeBP`\>Ve
ps=null; .>z][2oz
} Bgmn2-
}catch(SQLException e){} iC
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DBUtils.closeConnection(conn); RwS@I/
} + [Hh,I7
} g$dsd^{O7
public long getLast(){ JG{j)O|L
return lastExecuteTime; 2Z20E$Cb
} 42>Ge>#F
public void run(){ CK,
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long now = System.currentTimeMillis(); {'16:dTJ
if ((now - lastExecuteTime) > executeSep) { drsB/
//System.out.print("lastExecuteTime:"+lastExecuteTime); -W,}rcj*|
//System.out.print(" now:"+now+"\n"); oK{ V7
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); UT}i0I9
lastExecuteTime=now; s1?[7yC
executeUpdate(); p4p@^@<>X
} wP,JjPUt
else{ nx0K$Ptq
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); qRbf2;
} Scv#zuv_
} 1Bxmm#
} eAPXWWAZJ1
//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 ~
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类写好了,下面是在JSP中如下调用。 h*ZC*eV>
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<% \QU^>23
CountBean cb=new CountBean(); Xl74@wq
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); [pVamE
CountCache.add(cb); /c):}PJ^#7
out.print(CountCache.list.size()+"<br>"); bI|2@HV2
CountControl c=new CountControl(); vM_:&j_?``
c.run(); jY_T/233d
out.print(CountCache.list.size()+"<br>"); !%dN<%Ah
%>