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: zG{jRth
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CountBean.java {Us^4Xe
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/* |bhv7(_
* CountData.java &3J^z7kU
* {jv+ JL"5
* Created on 2007年1月1日, 下午4:44 ohs`[U=%~
* fg lN_
* To change this template, choose Tools | Options and locate the template under ox_DEg7l
* the Source Creation and Management node. Right-click the template and choose Q}cti/
* Open. You can then make changes to the template in the Source Editor. lEw;X78+
*/ |~#A?mK-
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package com.tot.count; ^Ku]8/ga
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/** C/QrkTi=
* JLz32 %-M
* @author a:OM I
*/ /r2S1"(q
public class CountBean { ZpMv16
private String countType; YQtq?&0Ct
int countId; ]')y(_{
/** Creates a new instance of CountData */ lr[T+nQ
public CountBean() {} mnBTZ/ZjS
public void setCountType(String countTypes){ m#R"~ >
this.countType=countTypes; Qv
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} MK1#^9Zr
public void setCountId(int countIds){ sSc~q+xz
this.countId=countIds; 'p78^4'PL
} )Gk?x$pY@
public String getCountType(){ PVIZ
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return countType; q[+h ~)
} )wXE\$
public int getCountId(){ ti$60Up
return countId; u+
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} .C&kWM&j
} oRJ!TAbD
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CountCache.java ]Yf^O @<<>
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/* x^ `IZ{!
* CountCache.java X
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* ExN$J
* Created on 2007年1月1日, 下午5:01 `.dwG3R
* Ujlbcv6+
* To change this template, choose Tools | Options and locate the template under 9HPmJ`b
* the Source Creation and Management node. Right-click the template and choose Ekik_!aB
* Open. You can then make changes to the template in the Source Editor. fJ0V|o
*/ P;K LN9/4
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package com.tot.count; Z:Vde^Ih
import java.util.*; >I<}:=
/** I3b*sx$
* / 9,'.
* @author .'$8Hj;@
*/ '9zKaL
public class CountCache { Q`NdsS2
public static LinkedList list=new LinkedList(); /Oi(5?Jn
/** Creates a new instance of CountCache */ XA(.O|VZ
public CountCache() {} (:o:_U
public static void add(CountBean cb){ b|@zjh;]A7
if(cb!=null){ "FhC"}N
list.add(cb); k}I65 ^l#
} H+-x.l`
} GN
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} F6{/iF
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CountControl.java =
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/* M2R krW#
* CountThread.java )siWc_Z4
* Xit@.:a;
* Created on 2007年1月1日, 下午4:57 BlZB8KI~
* ~c]
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* To change this template, choose Tools | Options and locate the template under r[T(R9k
* the Source Creation and Management node. Right-click the template and choose ){z#Y#]dP
* Open. You can then make changes to the template in the Source Editor. tw=A]
a*
*/ k.2GIc:5
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package com.tot.count; $G 6kS@A
import tot.db.DBUtils; D!#B*[|
import java.sql.*; &<_q00F
/** 7'65+c[&
* gmn b
* @author h-sO7M0E]
*/ U1 *P
public class CountControl{ r$-P
private static long lastExecuteTime=0;//上次更新时间 8 a]g>g
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 6J#R1.h
/** Creates a new instance of CountThread */ w^^l,
public CountControl() {} nd,\<}uP9
public synchronized void executeUpdate(){ L+T'TC:
Connection conn=null; :?LNP3}
PreparedStatement ps=null; {Rb;1 eYj
try{ )m+O.`x
conn = DBUtils.getConnection(); t#8QyN
conn.setAutoCommit(false); ZMr[:,Jp
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 4}t&yu<P>
for(int i=0;i<CountCache.list.size();i++){ 1Y;.fZE
CountBean cb=(CountBean)CountCache.list.getFirst(); isy[RAP<
CountCache.list.removeFirst(); 2hso6Oy/v{
ps.setInt(1, cb.getCountId()); o2bmsnXQ
ps.executeUpdate();⑴ hO{&bY0
//ps.addBatch();⑵ B2*>7 kc_s
} n@R/zy
//int [] counts = ps.executeBatch();⑶ +-SO}P
conn.commit(); wtf H3v
}catch(Exception e){ ujN~l_4
e.printStackTrace(); {dP6fr1z
} finally{ S.`hl/
try{ z C$F@
if(ps!=null) { F(Zf=$cx
ps.clearParameters(); iPY)Ew`Im
ps.close(); [`s.fkb8
ps=null; Z]WX 7d
} 0_-o]BY
}catch(SQLException e){} ?(Tin80=r
DBUtils.closeConnection(conn); W1Fhx`
} y`5
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} >?)_, KL
public long getLast(){ YU`k^a7%
return lastExecuteTime; "VHT5k
} ~`^kP.()
public void run(){ BB9eQ:
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long now = System.currentTimeMillis(); {oF;ZM'r
if ((now - lastExecuteTime) > executeSep) { Vr"'O6
//System.out.print("lastExecuteTime:"+lastExecuteTime); \CE+P5
//System.out.print(" now:"+now+"\n"); R.l!KIq
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 2M\7j
lastExecuteTime=now; n@h$V\&\iM
executeUpdate(); `F1Yfm
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} 4+nZ4a>LH?
else{ |+JO]J#bc
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); p,|)qr:M
} R/fE@d2~In
} u rQvJ
} F7w\ctUP
//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 wu11)HFL|z
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类写好了,下面是在JSP中如下调用。 -|s%5p|
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<% _D@QsQ_Z
CountBean cb=new CountBean(); } _];yw
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); Wd(|w8J{a
CountCache.add(cb); \fSruhD
out.print(CountCache.list.size()+"<br>"); ]9'F<T= $_
CountControl c=new CountControl(); N+5f.c+S-
c.run(); Y*Ay=@z=y
out.print(CountCache.list.size()+"<br>"); 7mv([}Va
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