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: 82l$]W 4
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CountBean.java MwbXZb{#"=
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/* Vea2 oQq
* CountData.java 5]pvHc
* #@FMH*?xX6
* Created on 2007年1月1日, 下午4:44 Z0HfrK#oU
* =?]H`T:
* To change this template, choose Tools | Options and locate the template under LK\L}<;1V
* the Source Creation and Management node. Right-click the template and choose yuIy?K
* Open. You can then make changes to the template in the Source Editor. Cw6\'p%l-\
*/ B;x5os
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package com.tot.count; Yuo:hF\DH
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/** Iv])s
* g>`
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* @author LtIp,2GP&_
*/ *-uA\
public class CountBean { Y;2WY0eq
private String countType; $eHYy,,
int countId; !\|_,pSB
/** Creates a new instance of CountData */ LCBP9Rftvd
public CountBean() {} U9"g;t+/
public void setCountType(String countTypes){ w5fVug/;P
this.countType=countTypes; #uTNf78X
} O0^m_
public void setCountId(int countIds){ )Y4;@pEU
this.countId=countIds; 9o%k [n
} e1cqzhI=nA
public String getCountType(){ e}l F#$
return countType; tVfZ~qJ
} )
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public int getCountId(){ O2x bHn4
return countId; `C pfQP&^
} XZ%3PMq
} nA owFdCD
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CountCache.java #aI(fQZe
rhff8C//'
/* xER-TT#S
* CountCache.java |"]#jx*8KC
* an q1zH
* Created on 2007年1月1日, 下午5:01 9w3KAca
* TAL,(&[s
* To change this template, choose Tools | Options and locate the template under ;|qbz]t2(
* the Source Creation and Management node. Right-click the template and choose "w7{,HP
* Open. You can then make changes to the template in the Source Editor. 5Z;iK(>IX
*/ v']Tusmg
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package com.tot.count;
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import java.util.*; z
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/** t@X{qm:%Z
* ]@Z[/z%~04
* @author r:{;HM+
*/ K;8{qQ*
public class CountCache { <C1w?d$9I
public static LinkedList list=new LinkedList(); edai2O
/** Creates a new instance of CountCache */ wjtFZGx&
public CountCache() {} uNKf!\Y
public static void add(CountBean cb){ J497
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if(cb!=null){ %-?k [DL6
list.add(cb); ^%5;Sc1V
} oU l0w~Xn
} tt4Z
} `d c&B
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CountControl.java \jmT#Gt`9
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/* z`H|]${X
* CountThread.java [_T6
* Ly46S
* Created on 2007年1月1日, 下午4:57 h 8<s(WR
* P*|qbY
* To change this template, choose Tools | Options and locate the template under y3XR:d1cg
* the Source Creation and Management node. Right-click the template and choose }|UTwjquBD
* Open. You can then make changes to the template in the Source Editor. Vp$<@Y
*/ /np05XhEa
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package com.tot.count; vRkVPkZ6|
import tot.db.DBUtils; ''^2rF^
import java.sql.*; y$Fk0s*>
/** }!uwWBw`
* Gq=tR `.
* @author + L[a
*/ %45*DT
public class CountControl{ 7Y?59
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private static long lastExecuteTime=0;//上次更新时间 GX+Gqj.
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 I*z|_}$
/** Creates a new instance of CountThread */ |.OS7Gt?
public CountControl() {} TO&^%d
public synchronized void executeUpdate(){ &t U&ZH
Connection conn=null; XE'3p6
PreparedStatement ps=null; AvVPPEryal
try{ B.A;1VE5
conn = DBUtils.getConnection(); /H?) qk
conn.setAutoCommit(false); <S^Hy&MD>
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ux8K$$$
for(int i=0;i<CountCache.list.size();i++){ o)wOXF
CountBean cb=(CountBean)CountCache.list.getFirst(); 1@t8i?:h
CountCache.list.removeFirst(); v4]#Nc$~T
ps.setInt(1, cb.getCountId()); ),>whCtsI
ps.executeUpdate();⑴ wwN kJ+
//ps.addBatch();⑵ c!kz wc(
} %x./>-[t
//int [] counts = ps.executeBatch();⑶ +TW,!.NBG
conn.commit(); fh*7VuAc
}catch(Exception e){ Cp?6vu|RA
e.printStackTrace(); "#:h#uRUb
} finally{ >Qqxn*O
try{ !'C8sNs
if(ps!=null) { n5 <B*
ps.clearParameters(); !
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ps.close(); 4d_Az'7`4
ps=null; W!+eJ!Da
} d(j
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}catch(SQLException e){} %+((F+[
DBUtils.closeConnection(conn); hWiHKR]
} e<{waJ1
} aA
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public long getLast(){ KBoW(OP4'
return lastExecuteTime; vjVa),2
} 29nMm>P.e
public void run(){ +W/{UddeKU
long now = System.currentTimeMillis(); SBaTbY0
if ((now - lastExecuteTime) > executeSep) { dUBf.2ry
//System.out.print("lastExecuteTime:"+lastExecuteTime); WOeG3jMz?
//System.out.print(" now:"+now+"\n"); (Z0.H3
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 8lyNg w1
lastExecuteTime=now; *x)u9rO]
executeUpdate(); tiy#b8
} O))j
else{ ,g 1~4,hqQ
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); (S?qxW?
} ?y@;=x!'
} #sv:)p
} C,8@V`
//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 #^_7i)=~
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类写好了,下面是在JSP中如下调用。 *l@T
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<% @.=2*e.z|b
CountBean cb=new CountBean(); VrKLEN\
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); MH]?:]K9V
CountCache.add(cb); 'X\C/8\
out.print(CountCache.list.size()+"<br>"); DB'3h7T
CountControl c=new CountControl(); Va4AE)[/*
c.run(); -j^G4J
out.print(CountCache.list.size()+"<br>"); _QtW)\)5\
%>