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: .6O"|
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CountBean.java A7!g
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/* GU't%[
* CountData.java RsU3Gi_Zdz
* nJRS.xs
* Created on 2007年1月1日, 下午4:44 Uie?9&3
* n .!Ym
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* To change this template, choose Tools | Options and locate the template under a $"ib
* the Source Creation and Management node. Right-click the template and choose +,:du*C
* Open. You can then make changes to the template in the Source Editor. <9=9b_z
*/ ky
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package com.tot.count; ^mAYBOE
*Ype>x{
/** -~eJn'W
* =.y*_Ja
* @author 22kp l)vbU
*/ 9ukg }_Hx
public class CountBean { #`GY}-hL!
private String countType; 2L AYDaS
int countId; T081G`li
/** Creates a new instance of CountData */ TF2>4 p
public CountBean() {} o7B[R) 4
public void setCountType(String countTypes){ &t5{J53
this.countType=countTypes; |IunpZV
} /h v4x9
public void setCountId(int countIds){ Ladsw
this.countId=countIds; <I}2k
} \%sVHt`c
public String getCountType(){ liR?
return countType; Q'k\8'x
} >5R<;#8
public int getCountId(){ {;2vmx9
return countId; &V|>dLT>A
}
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} !*2%"H*
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CountCache.java b':|uu*/
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/* a[lY S{
* CountCache.java AxxJk"v'y
* 7bxA]s{m
* Created on 2007年1月1日, 下午5:01 %{6LUn
* ^m_yf|D$
* To change this template, choose Tools | Options and locate the template under _C\[DR0n
* the Source Creation and Management node. Right-click the template and choose C"lJl k9g^
* Open. You can then make changes to the template in the Source Editor. 3~e8bcb
*/ @"T"7c?Cv
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package com.tot.count; yqSs,vz
import java.util.*; )otb>w5
/** Y!6/[<r$~k
* *5<Sr q'
* @author y2O4I'/5<
*/ l"n{.aL
public class CountCache { ??hJEE
public static LinkedList list=new LinkedList(); ;,&8QcSVY
/** Creates a new instance of CountCache */ Sx
public CountCache() {} r%DFve:%
public static void add(CountBean cb){ T]Nu)
if(cb!=null){ `IYuz:
list.add(cb); 7u\*_mrv
} :b[`
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} 8@NH%zWBp
} R(j1n,c]
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CountControl.java 1Y_w5dU
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/* W)(^m},*8D
* CountThread.java J8y0d1SG
* B=
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* Created on 2007年1月1日, 下午4:57 ?=GXqbS"
* %AF5=
* To change this template, choose Tools | Options and locate the template under {b]aC
* the Source Creation and Management node. Right-click the template and choose :a:[.
* Open. You can then make changes to the template in the Source Editor. A?G IBjs
*/ 0iCPi)B
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package com.tot.count; *`(
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import tot.db.DBUtils; 2!N8rHRt
import java.sql.*; co_oMc
/** HaA1z}?n
* !h&g7do]Z
* @author FZB~|3eq{
*/ P?BGBbC
public class CountControl{ )o!XWh
private static long lastExecuteTime=0;//上次更新时间 MH|]\
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 u6:pV.p
/** Creates a new instance of CountThread */ >]'yK!a?
public CountControl() {} cYNJhGY
public synchronized void executeUpdate(){ [NnauItI
Connection conn=null; 1Xy]D
PreparedStatement ps=null; eMK+X \
try{
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conn = DBUtils.getConnection(); g%[n4
conn.setAutoCommit(false); fIoIW&iy
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); D j\e@?Y
for(int i=0;i<CountCache.list.size();i++){ 66snC{gU
CountBean cb=(CountBean)CountCache.list.getFirst(); vUC!fIG
CountCache.list.removeFirst(); {#IPf0O
ps.setInt(1, cb.getCountId()); ryO$6L
ps.executeUpdate();⑴ 4([.xT
//ps.addBatch();⑵ A`O <6
} Do?P<x o
//int [] counts = ps.executeBatch();⑶ Z: 2I/
conn.commit(); j:5%ppIY
}catch(Exception e){ {5c]Mn"r
e.printStackTrace(); _RMQy~&b
} finally{ O`FqD{@V
try{ _i}wK?n
if(ps!=null) { Bz8 &R|~>"
ps.clearParameters(); ~Pk0u{,4XQ
ps.close(); T+"f]v
ps=null; 2k7bK6=nm
} Al)$An-
}catch(SQLException e){} ]kktoP|D
DBUtils.closeConnection(conn); e^).W3SK]
} =4C}{IL
} ScnY3&rc
public long getLast(){ 9-h.|T2il
return lastExecuteTime; Y5A~E#zw
} bggusK<
public void run(){ kD~uGA
long now = System.currentTimeMillis(); pLoy
if ((now - lastExecuteTime) > executeSep) { &ju-
//System.out.print("lastExecuteTime:"+lastExecuteTime); $]d*0^J 6
//System.out.print(" now:"+now+"\n"); vfvlB[
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); !MZw#=D`
lastExecuteTime=now; <MD;@_Nz\
executeUpdate(); Qb^q+C)o]
} :x>T}C<Y
else{ &R$Q\,
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); >POO-8Q
} vM0_>1nN
} C;1PsSE+A
} B5=3r1Ly
//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 RpQ*!a~O
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类写好了,下面是在JSP中如下调用。 }*;EFR 6'
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<% go|>o5!g
CountBean cb=new CountBean(); 3_ 2hC!u!K
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); \d68-JS@~
CountCache.add(cb); vP]9;mQ
out.print(CountCache.list.size()+"<br>"); i*tv,f.(
CountControl c=new CountControl(); ~^o=a?L`<
c.run(); to3?$-L
out.print(CountCache.list.size()+"<br>"); swr"k6;G
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