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: V^?+|8_(
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CountBean.java %{o5}TqD
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/* iM}cd$r{
* CountData.java Vs9fAAXS4
* LH<--#K
* Created on 2007年1月1日, 下午4:44 zjVb+Z\n
* SznNvd <
* To change this template, choose Tools | Options and locate the template under ^@L
* the Source Creation and Management node. Right-click the template and choose B;?a. 81~
* Open. You can then make changes to the template in the Source Editor. $,'r}
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*/ 7xWX:2l*?
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package com.tot.count; bumS>:
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/** js k<N
* C{e:xGJK
* @author uXK$5"
*/ &=_YL
public class CountBean { )[%#HT
private String countType; 9)H~I/9Y
int countId; : @YZ6?hf
/** Creates a new instance of CountData */ U
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public CountBean() {} _3kAN.g
public void setCountType(String countTypes){ iCz,|;w%
this.countType=countTypes; J*$ !^\s
} *B@<{x r
public void setCountId(int countIds){ |%b' L.$4
this.countId=countIds; &z%7Nu
} /R
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public String getCountType(){ D>LdDhNn,`
return countType; k('2K2P
} [.3M>,)+-
public int getCountId(){ .,tf[w 71
return countId; +F+jC9j(<
} GT#i Y*
} MF%9
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CountCache.java \kC/)d
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/* $Fr$9 jq&
* CountCache.java Eepy%-\
* -C.eXR{s
* Created on 2007年1月1日, 下午5:01 $yc&f(Tv
* ^\Jg
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* To change this template, choose Tools | Options and locate the template under h9SS
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* the Source Creation and Management node. Right-click the template and choose b:W]L3Z8
* Open. You can then make changes to the template in the Source Editor. C 5)G^
*/ o5AyJuS-u$
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package com.tot.count; njvmf*A?S
import java.util.*; 'B6D&xn'%&
/** O+z-6:`
* %Z.>)R4
* @author udW,
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*/ =p^*y-z
public class CountCache { 2nOQ48haT
public static LinkedList list=new LinkedList(); Rw Y)
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/** Creates a new instance of CountCache */ &eg]8kV
public CountCache() {} #Wh"_zpM+
public static void add(CountBean cb){ gp(w6:w
if(cb!=null){ }2JSa8
list.add(cb); NeeymyW
} 6t*=.b,N
} zBqr15
} qdO^)uJJ
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CountControl.java =cqaA^HQL
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/* l
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* CountThread.java =d(
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* ")ZHa qEB
* Created on 2007年1月1日, 下午4:57 *>Om3[D
* >TK`s@jdSV
* To change this template, choose Tools | Options and locate the template under [o>/2
* the Source Creation and Management node. Right-click the template and choose ;jI\MZ~l\
* Open. You can then make changes to the template in the Source Editor. G}] ZZ
*/ 2t#9ih"9
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package com.tot.count; ou96
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import tot.db.DBUtils; Gz^g!N[
import java.sql.*; ib uA~\5
/** x$6-7<p
* Awe\KJ^`
* @author oLB pG1Va
*/ WMl_$Fd6
public class CountControl{ .DCp)&m
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private static long lastExecuteTime=0;//上次更新时间 }RW4
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 BOfO$J}
/** Creates a new instance of CountThread */ %Sxy!gGz%%
public CountControl() {} \h_hd%'G
public synchronized void executeUpdate(){ ${e(#bvGZ
Connection conn=null; $?I^Dk
PreparedStatement ps=null; 9$S2:2(G
try{ I8`.eqV
conn = DBUtils.getConnection(); Dt.OZ4w5
conn.setAutoCommit(false); ,CwhpW\Y
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ;2%3~L8?V
for(int i=0;i<CountCache.list.size();i++){ b\H(Lq17
CountBean cb=(CountBean)CountCache.list.getFirst(); bncK8SK
CountCache.list.removeFirst(); 4zfgtg(
ps.setInt(1, cb.getCountId()); AB+Zc
]
ps.executeUpdate();⑴ Fv e,&~
//ps.addBatch();⑵ QDxL y aL
} d v@6wp:
//int [] counts = ps.executeBatch();⑶ uCmdNY
conn.commit(); 7|65;jm+
}catch(Exception e){ lm-ubzJN
e.printStackTrace(); v
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} finally{ r|0C G^:C
try{ Re,0RM\
if(ps!=null) { WDgp(Av!
ps.clearParameters(); nE::9Yh8z
ps.close();
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ps=null; zCPjuS/~
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} 1NJ*EzJ~?
}catch(SQLException e){} Ya\G/R
DBUtils.closeConnection(conn); _%<7!|"
} KGK8;Q,O
} _H:SoJ'
public long getLast(){ Na3tK}x
return lastExecuteTime; ux{OgFfi
} XwlUkw"q
public void run(){ }R}tIC-:
long now = System.currentTimeMillis(); HQ2in_'
if ((now - lastExecuteTime) > executeSep) { I~4`NV0
//System.out.print("lastExecuteTime:"+lastExecuteTime); =>-b?F0(c
//System.out.print(" now:"+now+"\n"); "fz-h
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); y~U+MtSf#
lastExecuteTime=now; %'^m6^g;
executeUpdate(); .8.ivfmJh
} )@))3
else{ EKwS~G.b!
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); X(Ef=:
} )Q7;)iPY#
} u'?t'I
}
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//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 Q"Q|]f*
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类写好了,下面是在JSP中如下调用。 $Q]`+:g*}
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<% x2|DI)J1'
CountBean cb=new CountBean(); !.3
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); '90B),c{
CountCache.add(cb); ub.pJJlC
out.print(CountCache.list.size()+"<br>"); yu}4L'e
CountControl c=new CountControl(); ,{zvGZ|
c.run(); MQ,$'Y5~H
out.print(CountCache.list.size()+"<br>"); b/ZX}<s(1=
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