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: 90Hjx>[
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CountBean.java n!E2_
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/* qJ_1*!!91
* CountData.java =)OC|?9C\
* .6pOvGKb
* Created on 2007年1月1日, 下午4:44 JkA|Qdj~Mr
* $Vv}XMxw
* To change this template, choose Tools | Options and locate the template under p=QYc)3F
* the Source Creation and Management node. Right-click the template and choose <vbIp&
* Open. You can then make changes to the template in the Source Editor. %AnW~v
*/ Y3ZK%OyPR
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package com.tot.count; ^5 t
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/** Ab1/.~^
* FCc=e{
* @author -6Mm#sX
*/ ARfRsPxr
public class CountBean { k 2%S`/:
private String countType; G 8Y+w
int countId; cxYfZ4++m
/** Creates a new instance of CountData */ %:qoV0DR
public CountBean() {} @)8]e
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public void setCountType(String countTypes){ 7CB#YP?E
this.countType=countTypes; u.|~$yP.!
} EC?Efc+O
public void setCountId(int countIds){ i(6J>^I
this.countId=countIds; Kt.~aaG_
} ;#G%U!p
public String getCountType(){ :'r6TVDW
return countType; 0D(cXzQP
} R& =f:sEi
public int getCountId(){ 8"vwU@cfC
return countId; >LF&EM]
} Ok%}|/P4
} '?GQ~Bf<>
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CountCache.java xkA2g[
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/* DjW$?>
* CountCache.java W%!@QY;E(
* !|m9|
* Created on 2007年1月1日, 下午5:01 ! ]Mc4!E
* \`,xgC9K
* To change this template, choose Tools | Options and locate the template under Ca $c;
* the Source Creation and Management node. Right-click the template and choose RwTzz]
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* Open. You can then make changes to the template in the Source Editor. xnq><4
*/ qA/bg
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package com.tot.count; ]R_G{%
import java.util.*; S9Yt 1qb
/** chAan~r[*
* =J|sbY"]
* @author M>_ = "atI
*/ I/UQ' xx
public class CountCache { 77:'I
public static LinkedList list=new LinkedList(); 8kW /DcLE
/** Creates a new instance of CountCache */ %TK&)Q% h5
public CountCache() {} O=jN&<rb
public static void add(CountBean cb){ DPJh5d
if(cb!=null){ MPRO
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list.add(cb); f(u&XuZ
} ]RFdLV?
} BEw{X|7
} 5 z]\$=TE
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CountControl.java F$hZRZ
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/* N5q725zJ
* CountThread.java ZcZ;$*
* j.QHkI1.
* Created on 2007年1月1日, 下午4:57 z*.v_Mx
* -WT3)On
* To change this template, choose Tools | Options and locate the template under e!o(g&wBj
* the Source Creation and Management node. Right-click the template and choose cj(X2L
* Open. You can then make changes to the template in the Source Editor. hswTn`f
*/ <FmBa4ONU
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package com.tot.count; T#iU+)-\%
import tot.db.DBUtils; GFR!n1Hv
import java.sql.*; u;n(+8sz
/** If}lJ6jZ
* ;1LG&h,K
* @author KP~-$NR
*/ !.+"4TF
public class CountControl{ &jJckT
private static long lastExecuteTime=0;//上次更新时间 =FBIrw{w
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 6f}e+ 80
/** Creates a new instance of CountThread */ |R'i:=
public CountControl() {} ]M4NpUM
public synchronized void executeUpdate(){ ~Ob8i 1S>
Connection conn=null; :k1$g+(lP
PreparedStatement ps=null; i f@W
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try{ iUNnPJh
conn = DBUtils.getConnection(); 5a$$95oL
conn.setAutoCommit(false); #O</\|aH)i
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); !s-/0ugZ
for(int i=0;i<CountCache.list.size();i++){ w<d*#$[,*
CountBean cb=(CountBean)CountCache.list.getFirst(); &`PbO
CountCache.list.removeFirst(); SLA#= K
ps.setInt(1, cb.getCountId()); >}F? <JB
ps.executeUpdate();⑴ L<@&nx
//ps.addBatch();⑵ $'$>UFR
} R|t;p!T
//int [] counts = ps.executeBatch();⑶ # ,P(isEZ"
conn.commit(); $GF&x>]]
}catch(Exception e){ HIPL!ss]
e.printStackTrace(); kGD|c=K}
} finally{ MYTS3(
try{ `D)S-7BR
if(ps!=null) { +(AwSh !
ps.clearParameters(); @9_)On9hZ
ps.close(); MhH);fn
ps=null; Z1]"[U[;
} lS3 _Ild
}catch(SQLException e){} )@c3##Zp)
DBUtils.closeConnection(conn); NS5 49S
} oYqE*mA
} \G=bj;&eF
public long getLast(){ \DyKtrnm%
return lastExecuteTime; gDhl-
} /'+4vXc@
public void run(){ 0=,'{Vz}A
long now = System.currentTimeMillis(); Q2$/e+
if ((now - lastExecuteTime) > executeSep) { s=\7)n=,M
//System.out.print("lastExecuteTime:"+lastExecuteTime); *eoq=,O
//System.out.print(" now:"+now+"\n"); mCrU//G
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); {Pvr??"r
lastExecuteTime=now; Isp_U5M
executeUpdate(); Nz @8
} di<B ~:l58
else{ sWW\bK0B4
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); y7;
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} Heohe|an
} t;XS;b%
} g)N54WV
//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 (lb`#TTGx
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类写好了,下面是在JSP中如下调用。 r1hD
%a
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<% dAwS<5!
CountBean cb=new CountBean(); wL'C1Vr
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); <
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CountCache.add(cb); `^f}$R|
out.print(CountCache.list.size()+"<br>"); K*[0dza$
CountControl c=new CountControl(); a}GAB@YI
c.run(); Vd[2u
out.print(CountCache.list.size()+"<br>"); KPg[-d
%>