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: `;zu1o
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CountBean.java o'9OPoof:.
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/* eA3`]XP.`b
* CountData.java 5d)'`hACe
* ]C9%]`
* Created on 2007年1月1日, 下午4:44 <K|3Q'(S
* ex0
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* To change this template, choose Tools | Options and locate the template under oHYD_8'f
* the Source Creation and Management node. Right-click the template and choose CnM+HN30o
* Open. You can then make changes to the template in the Source Editor. n0Qh9*h
*/ :u[
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package com.tot.count; O('i*o4!}
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/** xCDA1y;j
* Fh*q]1F
* @author XHwZ+=v
*/ HV#?6,U}
public class CountBean { 9q@z[+X
private String countType; X}n&`y{/
int countId; 1]a*Oer}
/** Creates a new instance of CountData */ hfl%r9o
public CountBean() {} b/a?\0^
public void setCountType(String countTypes){
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this.countType=countTypes; hY4)W
} 1t~S3Q||>]
public void setCountId(int countIds){ n.;5P {V1
this.countId=countIds; =woqHTR
} (ffOu#RQ3
public String getCountType(){ 9RCB$Ka6X
return countType; q?e16M
} /j=DC9_
public int getCountId(){ ,}xpYq_/
return countId; Vq)|gF[6i
} #`YxoY `
} b#/V;
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CountCache.java 1@1+4P0NF[
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/* Zu [?'
* CountCache.java b.w(x*a
* c_D,MW\IC
* Created on 2007年1月1日, 下午5:01 oHc-0$eMKY
* 3 cV+A]i
* To change this template, choose Tools | Options and locate the template under #XYLVee,
* the Source Creation and Management node. Right-click the template and choose gMoyy
* Open. You can then make changes to the template in the Source Editor. 'Wx\"]:
*/ 5VoOJ_hq
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package com.tot.count; FrAqTz
import java.util.*; 9;xL!cy
/** .:|#9%5
* *`QdkVER
* @author ~L4*b*W
*/ Qw{\sCH>
public class CountCache { >%jEo'0;_
public static LinkedList list=new LinkedList(); 3;-@<9
/** Creates a new instance of CountCache */ Jnu}{^~
public CountCache() {} rSc,\upz
public static void add(CountBean cb){ a?xq*|?
if(cb!=null){ bH)8UQR%
list.add(cb); 5{!a+
} /pSUn"3
} f)ucC$1=
} ~(l2%(3G
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CountControl.java r['=a/.C
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/* ?Uy*6YS
* CountThread.java YWn6wzu%Vc
* /!&b'7y
* Created on 2007年1月1日, 下午4:57 c?V*X-
* 5qeS|]^`
* To change this template, choose Tools | Options and locate the template under ;nAg4ll8Q
* the Source Creation and Management node. Right-click the template and choose 7zJh;f/
* Open. You can then make changes to the template in the Source Editor. ^V0{Ew/x
*/ X{9JSq
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package com.tot.count; 2gC&R1H
import tot.db.DBUtils; 0x9F*i_
import java.sql.*; f@xfb
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/** k1 LtqV
* Y/eN)
* @author )2<B$p
*/ ^%'tD
public class CountControl{ >w]k3MC
private static long lastExecuteTime=0;//上次更新时间 sgb+@&}9n
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 IW] 841
/** Creates a new instance of CountThread */ ~gLEh tW
public CountControl() {} }TAGr 0
public synchronized void executeUpdate(){ )2^/?jK
Connection conn=null; 0z'={6,
PreparedStatement ps=null; wEHrer
try{ 9'/ |?I
conn = DBUtils.getConnection(); #QyK?i*
conn.setAutoCommit(false); l]58P
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); Z+h70,|
for(int i=0;i<CountCache.list.size();i++){ ~jRk10T(B
CountBean cb=(CountBean)CountCache.list.getFirst(); UV
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CountCache.list.removeFirst(); xjn8)C
ps.setInt(1, cb.getCountId()); PE6u8ZAb"
ps.executeUpdate();⑴ a*n%SUP
//ps.addBatch();⑵ Ow .)h(y/
} r#6l?+W ;
//int [] counts = ps.executeBatch();⑶ ,ovv
conn.commit(); /NN[gz
}catch(Exception e){ fE7a]REK
e.printStackTrace(); )zc8bS
} finally{ @,>=X:7
try{ ~|B!.+
if(ps!=null) { (a)@<RF`Q}
ps.clearParameters(); Qig!NgOM
ps.close(); YV _I-l0
ps=null; C[<\ufclD
} )hZ}$P1
}catch(SQLException e){} _%p9B#X<>
DBUtils.closeConnection(conn); 5z(>4 d!
} @vYN7
} E.Q}
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public long getLast(){ n+F-,=0
return lastExecuteTime; (+Nmio
} 8IIdNd
public void run(){ !=Kay^J~.
long now = System.currentTimeMillis(); x;?1#W
if ((now - lastExecuteTime) > executeSep) { 5SWX v+
//System.out.print("lastExecuteTime:"+lastExecuteTime); *d,n2a#n5
//System.out.print(" now:"+now+"\n"); ADl>~3b
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); F~@1n,[
lastExecuteTime=now; 6x3Ew2
executeUpdate(); -Fw4;&>
} bHo?Rw!.
else{ RKJWLofX&
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); JjO/u>A3;7
} @Q1F#IU
} $O</akn;
} \,IDLXqp
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 1eR{~ ,
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类写好了,下面是在JSP中如下调用。 s8I77._s
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<% =z/mI y<
CountBean cb=new CountBean(); sbiDnRf
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); rJ~(Xu>,s
CountCache.add(cb); Fe2-;o
out.print(CountCache.list.size()+"<br>"); d?qO`-
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CountControl c=new CountControl(); r- "`Abev
c.run(); )Jjw}}$}Y
out.print(CountCache.list.size()+"<br>"); pS)X\Xyw
%>