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: o'_eLp
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CountBean.java
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/* e$`;z%6y
* CountData.java }XD=N#p@z
* 0.wNa~_G|
* Created on 2007年1月1日, 下午4:44 :z`L)
* W0S\g#
* To change this template, choose Tools | Options and locate the template under bg2r
* the Source Creation and Management node. Right-click the template and choose vt#&YXu{A
* Open. You can then make changes to the template in the Source Editor. Am<){&XT
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*/ qzWnl[3
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package com.tot.count; 8&:dzS
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/** ZEB,Q~
* %_(^BZd
* @author B A
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*/ J u"/#@
public class CountBean { [U,hb1Wi3
private String countType; :j[=
int countId; Bxf&gDwjgr
/** Creates a new instance of CountData */ IN@ =UAc&
public CountBean() {} \;Sl5*kr
public void setCountType(String countTypes){ w&Z.rB?
this.countType=countTypes; fskc'%x
} ^YB3$:@$U
public void setCountId(int countIds){ )&[ol9+\
this.countId=countIds; r.' cjUs
} o,qUf
public String getCountType(){ K8uqLSP '
return countType; 6RfS_
} MFz6y":~
public int getCountId(){ +.a->SZ5"
return countId; *iUR1V Y
} ?s]?2>p
} ^3C%&
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CountCache.java :m0pm@
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/* g6H` uO
* CountCache.java brdY97s4
* n],"!>=+
* Created on 2007年1月1日, 下午5:01 7Q|v5@;pU
* \98|.EG
* To change this template, choose Tools | Options and locate the template under {A\y4D@
* the Source Creation and Management node. Right-click the template and choose pYj}
* Open. You can then make changes to the template in the Source Editor. gb26Y!7%
*/ '/fueku
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package com.tot.count; -yMD9b
import java.util.*; ?^U1~5ff)
/** &g!yRvM!;Q
* p@3 <{kLm
* @author iwfH~
*/ ={I(i6
public class CountCache { [ z{}?
public static LinkedList list=new LinkedList(); 8p]Krs:
/** Creates a new instance of CountCache */ )5x,-m@
public CountCache() {} #"TL*p
public static void add(CountBean cb){ W3xObt3w\
if(cb!=null){ s-S|#5
list.add(cb); {'o\#4Wk
} 3JZ9 G79H
} zrV~7$HL
} J6J;
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CountControl.java CMfR&G,)
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/* }^PdW3O*m,
* CountThread.java 2*Mu"v,
*
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* Created on 2007年1月1日, 下午4:57 ;h4w<OqcM
* | EFbT>
* To change this template, choose Tools | Options and locate the template under 8'0KHn{#
* the Source Creation and Management node. Right-click the template and choose G}`Hu_ [\)
* Open. You can then make changes to the template in the Source Editor. Ekz)Nh)vGR
*/ rlkg.e6
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package com.tot.count; ;CA7\&L>
import tot.db.DBUtils; nn/_>%Y
import java.sql.*; gX]'RBTb
/**
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* T0BM:ofx
* @author W4=<hB
*/ 7;NvR4P%
public class CountControl{ B3yp2tncj
private static long lastExecuteTime=0;//上次更新时间 tH9BC5+r}
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 `BY&&Bv#?
/** Creates a new instance of CountThread */ vH vwH
public CountControl() {} Nk shJ2
public synchronized void executeUpdate(){ %|3NCyJ*7
Connection conn=null; 6M@m`c
PreparedStatement ps=null; Zc*gRC
try{ ^4tz*i
conn = DBUtils.getConnection(); }"AGX
conn.setAutoCommit(false); E"b"VB
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); vU,
]UJ}
for(int i=0;i<CountCache.list.size();i++){ B1 [O9 U:
CountBean cb=(CountBean)CountCache.list.getFirst(); x2z%J,z@4
CountCache.list.removeFirst(); >=ng?
ps.setInt(1, cb.getCountId()); g/ x\#W
ps.executeUpdate();⑴ /qO?)p3gk
//ps.addBatch();⑵ EXT_x q
} Z#062NL
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//int [] counts = ps.executeBatch();⑶ fQ~YBFhlr
conn.commit(); eX9H/&g
}catch(Exception e){ !e:HE/&>i
e.printStackTrace(); =#{i;CC%
} finally{ *M()z.N
try{ b+mh9q'5E
if(ps!=null) { AME6Zu3Y
ps.clearParameters(); Js!V,={iX
ps.close(); RLX?3u&
ps=null; W\<p`xHk
} oF#]<Z\
}catch(SQLException e){} m_r_4BP
DBUtils.closeConnection(conn); #:M)a?E/%
} 1|%C66f^
} &B>YiA
public long getLast(){ UP |#WegO
return lastExecuteTime; HtGGcO'bqg
} yX;v
public void run(){ s~Od(,K
long now = System.currentTimeMillis(); 7I<] ;j
if ((now - lastExecuteTime) > executeSep) { F#$[jh$
//System.out.print("lastExecuteTime:"+lastExecuteTime); ejC== Fkc
//System.out.print(" now:"+now+"\n"); N;d@)h(N!
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); *27*&&=)H
lastExecuteTime=now; m'suAj0
executeUpdate(); WjvD C"
} gDjs:]/YR
else{ XxEKv=_bc
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ,-{2ai_
} $@:z4S(
} 7nL3+Pq
} X?Mc"M
//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 bol#[_~
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类写好了,下面是在JSP中如下调用。 x?MSHOia`P
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<% Mlr}v^"G
CountBean cb=new CountBean(); zE\@x+k.
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); {9C+=v?
CountCache.add(cb); O8%Y .SK
out.print(CountCache.list.size()+"<br>"); >E`p@
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CountControl c=new CountControl(); b_T?jCyW
c.run(); @( H
out.print(CountCache.list.size()+"<br>"); =~~Y@eX
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