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: pM$ @m]
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CountBean.java ZwJciT!_~
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/* ;;#nV$
* CountData.java y:so
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* ;sQbn|=e"
* Created on 2007年1月1日, 下午4:44 @EZ>f5IO+
* C3"&sdLb$
* To change this template, choose Tools | Options and locate the template under $G";2(-k
* the Source Creation and Management node. Right-click the template and choose rxE&fjW
* Open. You can then make changes to the template in the Source Editor. 0D3OE.$0
*/ tbur$00
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package com.tot.count; FmT
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/** esq<xuZM4
* %KV2<t?
* @author #x)}29%e#
*/ "'{OIP
public class CountBean { $h[Yz l
private String countType; j$PI,`
int countId; TmP8q
/** Creates a new instance of CountData */ /tC9G@Hl
public CountBean() {} ]Z@k|Nw
public void setCountType(String countTypes){ gxM[V>[
this.countType=countTypes; mK\aI
} ;'1Apy
public void setCountId(int countIds){ /H&aMk}J@y
this.countId=countIds; TA;,>f*
} uBeNXOre
public String getCountType(){ ntH T
return countType; P;GprJ`l
} qx%jAs+~
public int getCountId(){ >]/dOH,A
return countId; 2%YXc|gGT
} &o.iUk
} otq,R6 ^
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CountCache.java In(NF#
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/* ~3 @*7B5Q
* CountCache.java Czu1 )y
* *8-p7,D
* Created on 2007年1月1日, 下午5:01 otnV-7)@
* 0vckoE
* To change this template, choose Tools | Options and locate the template under +Jq`$+%C
* the Source Creation and Management node. Right-click the template and choose !;WbOnLP
* Open. You can then make changes to the template in the Source Editor. -1m vhR~
*/ d}% (jJ(I
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package com.tot.count; lU$X4JBzS
import java.util.*; ^x3EotQ\
/** IwRQL%
* 1v]t!}W:6
* @author W-Of[X{<
*/ ZNy9_a:dX
public class CountCache { 6/7F">@j
public static LinkedList list=new LinkedList(); jtLnj@,
/** Creates a new instance of CountCache */ |[WL2<
public CountCache() {} Q
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public static void add(CountBean cb){ V.j#E1 P
if(cb!=null){ /Sj_y*x1e
list.add(cb); ;Jo*|pju
} $jcz?vH
} k~|ZO/X@l%
} cG(0q[
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CountControl.java gMay
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/* pn*d[M|k
* CountThread.java
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* iiN?\OO^~
* Created on 2007年1月1日, 下午4:57 Sw
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* D;C5,rNt
* To change this template, choose Tools | Options and locate the template under %mmxA6I
* the Source Creation and Management node. Right-click the template and choose .f%vDBJS
* Open. You can then make changes to the template in the Source Editor. UzJ!Y / 5
*/ F*!gzKZ"
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package com.tot.count; hU+#S(t>b
import tot.db.DBUtils; Xj;2h{#s
import java.sql.*; kPedX
/** )|:8zDuJ
* @?M;'xMbB
* @author 40+fGRyOL
*/ ](n69XX_
public class CountControl{ !ABLd|tP
private static long lastExecuteTime=0;//上次更新时间 un&>
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 dcP88!#5-
/** Creates a new instance of CountThread */ w= B
public CountControl() {} cf&C|U
public synchronized void executeUpdate(){ )BpIxWd?
Connection conn=null; vVdxi9yk
PreparedStatement ps=null; .S(^roM;+
try{ ku-cn2M/
conn = DBUtils.getConnection(); VLx T"]f
conn.setAutoCommit(false); iz(m3k:w
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); %|bN@@
for(int i=0;i<CountCache.list.size();i++){ .W-=x,`hY4
CountBean cb=(CountBean)CountCache.list.getFirst(); pKYLAt+^>
CountCache.list.removeFirst(); *V<)p%l.
ps.setInt(1, cb.getCountId()); 3l+|&q[v
ps.executeUpdate();⑴ ^@Y9!G=
//ps.addBatch();⑵ &gJW6<
} d}pGeU'
//int [] counts = ps.executeBatch();⑶ \CDAFu#
conn.commit(); P 4H*jy@?
}catch(Exception e){ `43vxcMg
e.printStackTrace(); 9Mnem*
} finally{ CP@o,v-
try{ bsMC#xT
if(ps!=null) { |&(H^<+Xp
ps.clearParameters(); qb9}&'@:
ps.close(); U#iT<#!l2
ps=null; VrudR#q
} E4hq}
}catch(SQLException e){} XWc|[>iO
DBUtils.closeConnection(conn); 69-$Wn43<
} "LXXs0
} dZ-Ny_@&
public long getLast(){ EO"=\C,
return lastExecuteTime; vg5E/+4gp%
} :nt}7Dn'
public void run(){ *:(1K%g
long now = System.currentTimeMillis(); M$#+W?m&
if ((now - lastExecuteTime) > executeSep) { 01-p
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//System.out.print("lastExecuteTime:"+lastExecuteTime); Qk|( EFQ9
//System.out.print(" now:"+now+"\n"); d{?)q
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); e5FCqNip'
lastExecuteTime=now; #% qqL
executeUpdate(); rdFs?hO
} pDP33`OFh
else{ <%he
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//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); rT o%=0P
} 1XQ87~
} E8+8{
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} vsjM3=
//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 gp%tMTI1
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类写好了,下面是在JSP中如下调用。 |%n|[LP'
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<% sek6+#|=
CountBean cb=new CountBean(); h!Z Z2[
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ER/\ +Z#Z
CountCache.add(cb); B>1M$3`E
out.print(CountCache.list.size()+"<br>"); B6-AIPb
CountControl c=new CountControl(); |WQD=J%~(
c.run(); oJhEHx[f
out.print(CountCache.list.size()+"<br>"); hcj{%^p
%>