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: |b*?
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CountBean.java i K12pw
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/* gFHTG
* CountData.java ,4ei2`wV
* !"<MsoY@
* Created on 2007年1月1日, 下午4:44 e46/{4F,
* <
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* To change this template, choose Tools | Options and locate the template under LE*h9((
* the Source Creation and Management node. Right-click the template and choose aj?a^}X
* Open. You can then make changes to the template in the Source Editor. 'JNElXqrv
*/ 2n `S5(V
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package com.tot.count; mZx&Xez_G
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/** RTv
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* lWqrU1Sjl
* @author %-<'QYYP
*/ #/I[Jqf
public class CountBean { ]|sAK%/
private String countType; 2 Sh
int countId; NMww>80
/** Creates a new instance of CountData */ ]ut5S>,"
public CountBean() {} $ZNu+tn
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public void setCountType(String countTypes){ 8G oh4T H
this.countType=countTypes; 3"G>>nC&
} *Mw_0Y
public void setCountId(int countIds){ 9:e YU
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this.countId=countIds; ~t^eiyv
} 6%fKuMpK(
public String getCountType(){ (4\d]*u5-c
return countType; [-)r5Dsdq
} i} N8(B(
public int getCountId(){ <x&%~6j
return countId; Tp0bS
} 5cEcTJL[C
} Y_]De3:V0B
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CountCache.java c wOJy>
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/* I(9R~q
* CountCache.java "h|'}7p
* {'AWZ(
* Created on 2007年1月1日, 下午5:01 ;q:jl~
* ($LLl;1
* To change this template, choose Tools | Options and locate the template under jaa"~5TO8
* the Source Creation and Management node. Right-click the template and choose #'q<v"w
* Open. You can then make changes to the template in the Source Editor. v*9<c{a
*/ 3 q`)*
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package com.tot.count; ;s~X
import java.util.*; MdXchO-Lyc
/** BSkDpr1C
* WyZL9K{?
* @author r)i>06Hd
*/ PI*82,f3dE
public class CountCache { &R$CZU
public static LinkedList list=new LinkedList(); JR@.R
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/** Creates a new instance of CountCache */ j~FD{%4N
public CountCache() {} ~j-cS
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public static void add(CountBean cb){ #Jna6
if(cb!=null){ HmZ{L +"
list.add(cb); yB3;
} l/Vo-#
} =i(?deR
} hRq3C1mR
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CountControl.java ~u.T- 0F
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/* JkGnKm9G
* CountThread.java %%Qo2^-
* rYp3(k3
* Created on 2007年1月1日, 下午4:57 }=v)Js
* wQ%mN[
* To change this template, choose Tools | Options and locate the template under Uz7^1.-g4
* the Source Creation and Management node. Right-click the template and choose d oB
* Open. You can then make changes to the template in the Source Editor. 4&HXkRs:
*/ b9"jtRTdz
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package com.tot.count; 3
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import tot.db.DBUtils; l9Q(xuhv
import java.sql.*; j+^oz'q
/** 1-PoZ[p-R
* $-c!W!H
* @author n=,\;3Y=
*/ ;3
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public class CountControl{ >+mD$:L
private static long lastExecuteTime=0;//上次更新时间 FVKW9"AyW
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 8&Myva
/** Creates a new instance of CountThread */ &bhq`>
public CountControl() {} 9m-)Xdoy
public synchronized void executeUpdate(){ 8v71e>
Connection conn=null; 93<:RV
PreparedStatement ps=null; dVQ-k
try{ 1pCieTz!PN
conn = DBUtils.getConnection(); 6O@J7P
conn.setAutoCommit(false); jA(>sz
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); zSE<"(a
for(int i=0;i<CountCache.list.size();i++){ :=9] c17=
CountBean cb=(CountBean)CountCache.list.getFirst(); }'OHE(s
CountCache.list.removeFirst(); VqE~c
ps.setInt(1, cb.getCountId()); } %'bullT
ps.executeUpdate();⑴ k"N(o(
//ps.addBatch();⑵ 5qf
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} zvvP81$W
//int [] counts = ps.executeBatch();⑶ ;r/;m\V
conn.commit(); yi^b)2G
}catch(Exception e){ 'SYo_!
e.printStackTrace();
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} finally{ ql GW.jY.
try{ jAh2N3)
if(ps!=null) { .0G6flD
ps.clearParameters(); CdUAy|!`R
ps.close(); '<R>E:5
ps=null; {} Bf
} uHIiH@S
}catch(SQLException e){} KIeT!kmDl
DBUtils.closeConnection(conn);
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} b7/AnSR~Jt
} A!vCb
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public long getLast(){ {}o>{&X
return lastExecuteTime; W[[bV
} Fxc)}i`
public void run(){ GdVhK:<>
long now = System.currentTimeMillis(); j,d*?'X
if ((now - lastExecuteTime) > executeSep) { X1tXqHJF}
//System.out.print("lastExecuteTime:"+lastExecuteTime); o&hIHfZri
//System.out.print(" now:"+now+"\n"); Jd,)a#<j
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); f1PN|
lastExecuteTime=now; >\ u<&>i
executeUpdate(); }YOL"<,:o
} ~Z ~v
else{ .d?%;2*{q
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); `mH %!{P
} f(D_FTTO
} l/y]nw
} IZ3{>NV
//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 3u>8\|8wz
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类写好了,下面是在JSP中如下调用。 |BZDhd9<{
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<% O g%U
CountBean cb=new CountBean(); fnCItK~y
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ySbqnw'
CountCache.add(cb); W2;N<[wa<u
out.print(CountCache.list.size()+"<br>"); f&4,?E;6%
CountControl c=new CountControl(); zNSu
c.run(); ];+#i"l
out.print(CountCache.list.size()+"<br>"); 65,(4Udz!
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