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: }$l8d/_$[
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CountBean.java b)N[[sOt
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/* +a|"{
* CountData.java Z+ixRch@-s
* v2d<o[[C
* Created on 2007年1月1日, 下午4:44 M|d={o9Hp
* *R BV'b
* To change this template, choose Tools | Options and locate the template under YQ;
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* the Source Creation and Management node. Right-click the template and choose N1%p"(
* Open. You can then make changes to the template in the Source Editor. WP}ixcq#
*/ C@1CanL@3
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package com.tot.count; m#JI!_~!
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/** X2qv^G,
* HN{z T&
* @author j.DHqHx
*/ T.kyV|
public class CountBean { kBo;h.[l
private String countType; -LTKpN`[@
int countId; ]nQ+nH
/** Creates a new instance of CountData */ I"-dTa
public CountBean() {} #<4--$Xo
public void setCountType(String countTypes){ mb&lCd^-
this.countType=countTypes; wq UQ"d
} k0L] R5W
public void setCountId(int countIds){ %Uy%kN_&
this.countId=countIds; Mi]I:ka
} (?vK_{
public String getCountType(){ 8!&nKy<Y
return countType; $xT1 1 ^
} D|l,08n"?
public int getCountId(){ r4u z} jl{
return countId; X1oGp+&
} Oa!
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} I.1D*!tz
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CountCache.java t0q_>T-kt
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/* i\)3l%AK]T
* CountCache.java Ql8bt77eI-
* b._m 8z ~
* Created on 2007年1月1日, 下午5:01 m[spn@SF
* e # 5BPI
* To change this template, choose Tools | Options and locate the template under LEZ&W;bCo
* the Source Creation and Management node. Right-click the template and choose ;$7v%Ls=
* Open. You can then make changes to the template in the Source Editor. rFey4zzz
*/ pLnB)z?
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package com.tot.count; 4 /'N|c.
import java.util.*; XV>@B $hu
/** 'Dath>Y=
* }$&xTW_
* @author D<bI2
*/ G(/DtY]
public class CountCache { %?9Ok
public static LinkedList list=new LinkedList(); z\T Lsx
/** Creates a new instance of CountCache */ Lg4YED9#
public CountCache() {} /ylc*3e'4
public static void add(CountBean cb){ 9[VxskEh
if(cb!=null){ /1d<P! H
list.add(cb);
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} gzf-)J
} e"k/d<
} 5dl,co{q
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CountControl.java T_LLJ}6M
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/* 71"+<C .
* CountThread.java ]a?bzOr,
* $shp(T,q
* Created on 2007年1月1日, 下午4:57 X:EEPGE
* (RE2I
* To change this template, choose Tools | Options and locate the template under Q9c)k{QZ
* the Source Creation and Management node. Right-click the template and choose #H~_K}Ks
* Open. You can then make changes to the template in the Source Editor. O,s. D,S
*/ P|xG\3@Z
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package com.tot.count; UV AJxqz%}
import tot.db.DBUtils; /[=E0_t+
import java.sql.*; I[d]!YI}F
/** I4=Xb^Ux
* =rFN1M/n{E
* @author
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*/ &;c>O
public class CountControl{
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private static long lastExecuteTime=0;//上次更新时间 vWjnI*6T#
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 X%}nFgqQ
/** Creates a new instance of CountThread */ QR0(,e$Dl
public CountControl() {} h/)_)
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public synchronized void executeUpdate(){ asVX82<
Connection conn=null; hH>``gK
PreparedStatement ps=null; o6a0'vU><
try{ W\cjdd
conn = DBUtils.getConnection(); ,SUT~oETP
conn.setAutoCommit(false); )d`mvZBn1
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); I:l01W;
for(int i=0;i<CountCache.list.size();i++){ +v7) 1y
CountBean cb=(CountBean)CountCache.list.getFirst(); Kct@87z
CountCache.list.removeFirst(); !wE}(0BTx
ps.setInt(1, cb.getCountId()); Z7a945Jd
ps.executeUpdate();⑴ BPv>$
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//ps.addBatch();⑵ cn`iX(ZgR
} !%)]56(
//int [] counts = ps.executeBatch();⑶ `@Oa lg
conn.commit(); + ulagE|7
}catch(Exception e){ !*{q^IO9v&
e.printStackTrace(); Vzg=@A#
} finally{ }m-"8\_D
try{ IG ~`i I
if(ps!=null) { -_N)E ))G
ps.clearParameters(); ;9a 6pz<
ps.close(); `]i
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ps=null; i=S~(gp
} "ju'UOcS/
}catch(SQLException e){} iE].&>w
DBUtils.closeConnection(conn); F@YKFk+a
} BuOgOYh9
} aZS7sV28
public long getLast(){ 3=mr
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return lastExecuteTime; H t(n%;<
} j5$GFi\kB
public void run(){ o\VUD
long now = System.currentTimeMillis(); (s<s@`
if ((now - lastExecuteTime) > executeSep) { ;C.S3}
//System.out.print("lastExecuteTime:"+lastExecuteTime); i^msjA
//System.out.print(" now:"+now+"\n"); ac{?+]8}
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); j<<3Pr
lastExecuteTime=now; `G9 l
executeUpdate(); 5GzFoy)j>
} 3FE( }G
else{ soRv1) el
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); yx38g
ca
} zeb=8Dg
:
} b97w^ah4gJ
} ULJ mSe
//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 AIYmS#V1W2
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类写好了,下面是在JSP中如下调用。 )!:sFa
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<% ]`g@UtD9`
CountBean cb=new CountBean(); &ANP`=
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); )kXhtjOl|
CountCache.add(cb); dt@P>rel
out.print(CountCache.list.size()+"<br>"); 2Os1C}m
CountControl c=new CountControl(); q? qC
c.run(); 'a6<ixgo0
out.print(CountCache.list.size()+"<br>"); O^Q7b7}y
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