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: XzIl`eH
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CountBean.java Ed_N[I
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/* CbwJd5tk
* CountData.java #wV8X`g
* a'2$nbp}
* Created on 2007年1月1日, 下午4:44 B)qWtMZx
* k&,~qoU
* To change this template, choose Tools | Options and locate the template under Q
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* the Source Creation and Management node. Right-click the template and choose G&4&-<
* Open. You can then make changes to the template in the Source Editor. r]b_@hT',
*/ 3+ @<lVew6
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package com.tot.count; LN@F+CyDc
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/** Zg'Q>.:
* XDFx.)t
* @author ~zJ?H<>
*/ Ib+Y~
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public class CountBean { V+VkY3
private String countType; 4<k9?)~(J
int countId; /+@p7FqlE
/** Creates a new instance of CountData */ }Q=!Y>Tc
public CountBean() {} dvt9u9Vg=
public void setCountType(String countTypes){ T`5bZu^c
this.countType=countTypes; -(f)6a+H
} MP!d4
public void setCountId(int countIds){ PX<J&rx
this.countId=countIds; a=hxJ1O
} ~])t 6i
public String getCountType(){ @Ub"5Fl4
return countType; J/[=p<I)
} 0cJWJOj&
public int getCountId(){ yuat" Pg
return countId; R}q>O5O
} r\/9X}y4z
} UFp,a0|
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CountCache.java A'jP7P
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/* "4uS3h2r
* CountCache.java C/TF-g-_Y
* e>(<eu~P
* Created on 2007年1月1日, 下午5:01 TWQG591
* f!!V${)X
* To change this template, choose Tools | Options and locate the template under X@K-^8
* the Source Creation and Management node. Right-click the template and choose P!+'1KR
* Open. You can then make changes to the template in the Source Editor. cm&I* 0\
*/ J6L K
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package com.tot.count; p2DrEId
import java.util.*; .ys6"V|31
/** ~TSy<t~%-
* gx\&_)w N
* @author Il=
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*/ 7z!tKs"TMT
public class CountCache { wnM9('\
public static LinkedList list=new LinkedList(); %l,,_:7{
/** Creates a new instance of CountCache */ B[Zjfc
public CountCache() {} V3c l~
public static void add(CountBean cb){
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if(cb!=null){ E#ul IgD
list.add(cb); }Ub6eXf(2
} XgLL!5`
} gG-BVl"59
} %we u 1f
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CountControl.java V>A.iim
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/* pXJpK@z
* CountThread.java n#wI@W>%+
* .zn;:M#T
* Created on 2007年1月1日, 下午4:57 Db;G@#x
* YRh BRE
* To change this template, choose Tools | Options and locate the template under Y6Lf@}2(i
* the Source Creation and Management node. Right-click the template and choose #ZYVc|sT+
* Open. You can then make changes to the template in the Source Editor. k;w- E
*/ .)<(Oj|4
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package com.tot.count; -lhLA`6_R
import tot.db.DBUtils; nIU 6h
import java.sql.*; 1rkE yh??
/** B:!W$<
* Z(Bp 0a
* @author ~[\_N\rm
*/ jC7&s$>Q"g
public class CountControl{ IFDZfx
private static long lastExecuteTime=0;//上次更新时间 ~wJFa'2
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 mw='dFt
/** Creates a new instance of CountThread */ /XhIx\40l
public CountControl() {} =u+d_'P7-R
public synchronized void executeUpdate(){ 2UFv9
Connection conn=null; )e a :Q?
PreparedStatement ps=null; (Nx;0"5IX
try{ h\PHKC2
conn = DBUtils.getConnection(); J,AR5@)1
conn.setAutoCommit(false); _c,'>aH=
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); +=.W<b
for(int i=0;i<CountCache.list.size();i++){ Kwg4sr5"D
CountBean cb=(CountBean)CountCache.list.getFirst(); n(L\||#+
CountCache.list.removeFirst(); 4Qo]nre!
ps.setInt(1, cb.getCountId()); R
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ps.executeUpdate();⑴ ,B0_MDA +
//ps.addBatch();⑵ ^Nmg07_R
} A` AaTP
//int [] counts = ps.executeBatch();⑶ Dg}
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conn.commit(); 69J4=5lX
}catch(Exception e){ hNd}Y'%V
e.printStackTrace(); lhw()u
} finally{ wAxrc+
try{ lhw ,J]0*
if(ps!=null) { I+dbZBX
ps.clearParameters(); FKT1fv[H
ps.close(); ui@2s;1t
ps=null; N9vP7
} yb/%?DNQT
}catch(SQLException e){} rwG CUo6Z
DBUtils.closeConnection(conn); 86\S?=J-b
} U)o$WH.b
} I;Bjfv5
public long getLast(){ UGuxV+Nwf
return lastExecuteTime; x
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} QC X8IIHG
public void run(){ cdG|m[
long now = System.currentTimeMillis(); kjtjw1\o
if ((now - lastExecuteTime) > executeSep) { Hv\-_>}K
//System.out.print("lastExecuteTime:"+lastExecuteTime); 7?kIVP1r
//System.out.print(" now:"+now+"\n"); ;Hj~n+
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); bf!M#QOk?
lastExecuteTime=now; FDv+*sZ
executeUpdate(); ijdXU8
} <F.Tx$s
else{ JGH60|
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); DNj"SF(J
} WN_pd%m
} TW9WMId
} 'I /aboDB
//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
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类写好了,下面是在JSP中如下调用。 H03jDM8Q
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<% %B)6$!x
CountBean cb=new CountBean(); IrWD%/$H
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ^-[ ?#]
CountCache.add(cb); gW1b~(
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out.print(CountCache.list.size()+"<br>"); %0mMz.f
CountControl c=new CountControl(); [_.5RPJP8
c.run(); mUz\ra;z
out.print(CountCache.list.size()+"<br>"); 6^c>,.R
%>