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: vaJl}^T
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CountBean.java rHM^_sYRb
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/* jO/cdLKX(
* CountData.java YQ.ci4.f
* :<mJRsDf
* Created on 2007年1月1日, 下午4:44 $2,tT;50g
* yXoNfsv
* To change this template, choose Tools | Options and locate the template under W9pY=9]p+
* the Source Creation and Management node. Right-click the template and choose 7{(UiQbf
* Open. You can then make changes to the template in the Source Editor. Z#B}#*<C
*/ a5R.
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package com.tot.count; wJ pb$;
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/** O_7}H)
* 0j;ZPqEf3
* @author ;HH%OfQq
*/ .ARM~{q6)@
public class CountBean { LT
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private String countType; }^0'IAXi
int countId; 4].o:d;`/
/** Creates a new instance of CountData */ Lui6;NY
public CountBean() {} H8I)D& cw
public void setCountType(String countTypes){ :IBP "
this.countType=countTypes; ;l~a|KW0
} 4r`I)
public void setCountId(int countIds){ X'<RqvDc5
this.countId=countIds; 1U#W=Fg'
} iN.
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public String getCountType(){ Q,JH/X
return countType; u6F>o+Td)
} ['Lo8 [
public int getCountId(){ m~*qS4
return countId; R.*;] R>M
} @'}2xw[eU
} (*P`
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CountCache.java Pg8boN]}
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/* l[IL~
* CountCache.java v0dzM/?*
* zN!yOlp5
* Created on 2007年1月1日, 下午5:01 c5$DHT@N"
* ?wPTe^Qtv
* To change this template, choose Tools | Options and locate the template under u9|Eos i
* the Source Creation and Management node. Right-click the template and choose ?k4Hk$V
* Open. You can then make changes to the template in the Source Editor. TK18U*z7J
*/ H390<`
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package com.tot.count; .pWRV<25
import java.util.*; w-ald?`
/** 5hy7}*dR
* a'|]_`36x
* @author -rI7ihr*
*/ APF`b
public class CountCache { 8 <;.[l
public static LinkedList list=new LinkedList(); Yg '(
/** Creates a new instance of CountCache */ B=K<k+{6"
public CountCache() {} /klo),|&
public static void add(CountBean cb){ >*gf1"
if(cb!=null){ )cRHt:
list.add(cb); Xe\}(O
} Mn/
} h ChO
} FT~c|ep.
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CountControl.java w9GY/]
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/* ";(m,if-
* CountThread.java ]kmAN65c
* #e-7LmO~
* Created on 2007年1月1日, 下午4:57 uKXU.u*C
* *vRHF1)L
* To change this template, choose Tools | Options and locate the template under > `eo 0
* the Source Creation and Management node. Right-click the template and choose Z"Hq{?l9
* Open. You can then make changes to the template in the Source Editor. <ZZfN@6
*/ ~I>|f
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package com.tot.count; xC _3&.
import tot.db.DBUtils; |>j^$^l~
import java.sql.*; HI D6h!
/** 8M!9gvcaO
* V4"o.G3\o
* @author i=b'_SZ'
*/ 0K^@P#{hd
public class CountControl{ Om:Gun\%
private static long lastExecuteTime=0;//上次更新时间 oSMIWwg7G
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 4jZt0
/** Creates a new instance of CountThread */ p +JOUW
public CountControl() {} 7SkW!5
public synchronized void executeUpdate(){ Z%.Ld2Q{
Connection conn=null; Dy. |bUB!f
PreparedStatement ps=null; 8sDw:wTC
try{ >/C,1}p[
conn = DBUtils.getConnection(); Ve[Kv07
conn.setAutoCommit(false); epk
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ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); T` v
for(int i=0;i<CountCache.list.size();i++){ t9W* N\
CountBean cb=(CountBean)CountCache.list.getFirst(); O[1Q#
CountCache.list.removeFirst(); mrE>o!
ps.setInt(1, cb.getCountId()); gEVoY,}/-U
ps.executeUpdate();⑴ 0""%@X]m
//ps.addBatch();⑵ <Vyl*a{%
} QB*AQ5-
//int [] counts = ps.executeBatch();⑶ p'/%"
conn.commit(); A#~CZQY^$
}catch(Exception e){ REJBm
e.printStackTrace(); #c<F,` gdi
} finally{ %7TG>tc
try{ K)`l >o1
if(ps!=null) { $Ovq}Rexc
ps.clearParameters(); JKYl
ps.close(); Jn0L_@
ps=null; B$97"$#u
} "\afIYS I
}catch(SQLException e){} g( eA?
DBUtils.closeConnection(conn); , YE+k`:
} x*^)B~7}
} H0lAu]~R_W
public long getLast(){ Rwmr [g
return lastExecuteTime; >?X(,c
} ]CnT4[f!
public void run(){ .a]av
long now = System.currentTimeMillis(); _32 o7}!x
if ((now - lastExecuteTime) > executeSep) { :bp8S@
//System.out.print("lastExecuteTime:"+lastExecuteTime); Wzh#dO?7
//System.out.print(" now:"+now+"\n"); Qo["K}Ty
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); pvqbk2BO
lastExecuteTime=now; l(tMo7iPa
executeUpdate(); g9gyx/'*
} QfU{W@!h
else{ r<kqs,-~
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 7bam`)n
} 9[\$\l
} +u7nx
} FVHR
//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 oJ}$ /_
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类写好了,下面是在JSP中如下调用。 pXxpEv
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<% ,#=;V"~9
CountBean cb=new CountBean(); ZEU/6.
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); #>\8m+h 9
CountCache.add(cb); bcprhb
out.print(CountCache.list.size()+"<br>"); :,dO7dJi
CountControl c=new CountControl(); L/J)OJe\
c.run(); ;=ERm=
out.print(CountCache.list.size()+"<br>"); %MUwd@,
%>