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: NG&_?|OmV
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CountBean.java 3Ug
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/* gy:%l
* CountData.java AwUi+|7r])
* \vfBrN
* Created on 2007年1月1日, 下午4:44 DHC+C4
* `IpA.| Y
* To change this template, choose Tools | Options and locate the template under ~rr 4ok
* the Source Creation and Management node. Right-click the template and choose E`H$YS3o
* Open. You can then make changes to the template in the Source Editor. x3ERCqTR
*/ x]mxD|?f
_/* U2.xS
package com.tot.count; :1q4"tv|
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/**
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* O#EV5FeF.
* @author D<i[LZd
*/ $QEilf;E
public class CountBean { @.$Xv>Jt$
private String countType; 7r+g8+4
int countId; ^[-el=oKn0
/** Creates a new instance of CountData */ V}o n|A
public CountBean() {} jeyLL<
public void setCountType(String countTypes){ CRve.e8J
this.countType=countTypes; pCpb;<JG
} 9~rUkHD
public void setCountId(int countIds){ )Rat0$6
this.countId=countIds; p Rdk>Ph
} I]"96'|N
public String getCountType(){ Xd E`d.
return countType; X2mREt9
} $N']TN
public int getCountId(){ /N>e&e[35\
return countId; WnwhSr2
} kc'pN&]r:
} "1q>At
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CountCache.java X7UuwIIP
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/* v1k)hFjPK
* CountCache.java
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* V~ ~=Qp+.
* Created on 2007年1月1日, 下午5:01 rdnno
* 6J~12TU,
* To change this template, choose Tools | Options and locate the template under w:Jrmx
* the Source Creation and Management node. Right-click the template and choose V]c;^
* Open. You can then make changes to the template in the Source Editor. GBFw+v/|4
*/ dLsn\m>
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package com.tot.count; <D&)OxEn\
import java.util.*; LNl#h
/** TvNY:m6.%
* MC0TaP
* @author 6+V\t+aug
*/ ]Q
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public class CountCache { =z{JgD/
public static LinkedList list=new LinkedList(); :{'k@J"|a
/** Creates a new instance of CountCache */ \ 6EKgC1
public CountCache() {} 7:]Pl=:X
public static void add(CountBean cb){ 4`Nt{
if(cb!=null){ lT\a2.E
list.add(cb); !|2VWI}
} ;o/>JHGj
} T,fI BD:
} >vrxP8_
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CountControl.java '^%~JyU
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/* 4E8JT#&
* CountThread.java ]maYUKqv}'
* !@u>A_
* Created on 2007年1月1日, 下午4:57 &)i|$J 2.
* <)g8yA
* To change this template, choose Tools | Options and locate the template under n/QF2&X7)
* the Source Creation and Management node. Right-click the template and choose jNwjK0?
* Open. You can then make changes to the template in the Source Editor. 6b8;}],|
*/ C
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package com.tot.count; p3ISWJa!
import tot.db.DBUtils; I"AYWo?
import java.sql.*; Mcw4!{l`
/** KPSh#x&I
* pqvOJ#?Q}=
* @author &"_u}I&\
*/ :"6q,W
public class CountControl{ I O%6 O
private static long lastExecuteTime=0;//上次更新时间 j9qREf9)
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 7;.xc{
/** Creates a new instance of CountThread */ Bhqft;Nuh
public CountControl() {} sGY_{CZ:
public synchronized void executeUpdate(){ eLwTaW !C
Connection conn=null; M-NV_W&M
PreparedStatement ps=null; y AF+bCXo
try{ eZ a:o1y
conn = DBUtils.getConnection(); jO9ip
conn.setAutoCommit(false); IM=bK U
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ZaFb*XRgS
for(int i=0;i<CountCache.list.size();i++){ #5sD{:f`
CountBean cb=(CountBean)CountCache.list.getFirst(); ;TQf5|R\K
CountCache.list.removeFirst(); 3`hUo5K
ps.setInt(1, cb.getCountId()); w)E@*h<Z
ps.executeUpdate();⑴ [MX;,%;;
//ps.addBatch();⑵ {vaaFs
} aI
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//int [] counts = ps.executeBatch();⑶ DPe]daF
conn.commit(); /9Q3iV$I]
}catch(Exception e){ LL!.c
e.printStackTrace(); 4!$
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} finally{ W-RqN!snJ8
try{ puSLqouTM
if(ps!=null) { I3u{zHVwI
ps.clearParameters(); ^Yr0@pE
ps.close(); #LcrI
ps=null; [\)oo
} K*K1(_x=
}catch(SQLException e){} *VSel4;\t
DBUtils.closeConnection(conn); OwzJO
} (dJI_A
} KH KS$D
public long getLast(){ y;"
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return lastExecuteTime; m!XI {F@x
} pl*~kG=
public void run(){ ?<X(]I.j
long now = System.currentTimeMillis(); 6XEZ4QP}
if ((now - lastExecuteTime) > executeSep) { u]C`6)>
//System.out.print("lastExecuteTime:"+lastExecuteTime); (A k\Lm
//System.out.print(" now:"+now+"\n"); i< (s}wg
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); (J$\-a7<f
lastExecuteTime=now; ,lYaA5&I
executeUpdate(); u%|zc=
} OQ/<-+<w
else{ >Dm8m[76
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ~KjJ\b)R
} h4&;?T S
} WiNT;v[
} 6,Hqb<(
//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 TmRxKrRs
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类写好了,下面是在JSP中如下调用。 ]*"s\ix
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<% x
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CountBean cb=new CountBean(); !&kL9A).
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 9G?ldp8
CountCache.add(cb); huFz97?y(
out.print(CountCache.list.size()+"<br>"); S^RUw
CountControl c=new CountControl(); noVa=aU^
c.run(); :bM+&EP
out.print(CountCache.list.size()+"<br>"); -*VKlZ8-
%>