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: _~pbqa,
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CountBean.java iI>A *,{,`
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/* {e5= &A
* CountData.java ZB&6<uw
* MfQ!6zE
* Created on 2007年1月1日, 下午4:44 fAmz4
* Z6pUZ[j,
* To change this template, choose Tools | Options and locate the template under B?qjkP
* the Source Creation and Management node. Right-click the template and choose :L;a:xSpn=
* Open. You can then make changes to the template in the Source Editor. D6^6}1WI
*/ wPl%20t
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package com.tot.count; 2"5v[,$1H
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/** = f i$}>\
* cAc@n6[`3
* @author ;>YzEo
*/
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public class CountBean { wf$s*|z
private String countType;
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int countId; 9,tej
/** Creates a new instance of CountData */ [9 RR8
public CountBean() {} 4e1Y/
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public void setCountType(String countTypes){ 9K&:V(gmw
this.countType=countTypes; k'"%.7$U!
} 7yba04D)
public void setCountId(int countIds){ ;\l,5EG
this.countId=countIds; {_Gs*<.
} PuO&wI]:
public String getCountType(){ hL5|69E
return countType; [mHdG2X
} `p7=t)5k
public int getCountId(){ J")#I91
return countId; ][]
} eIo7F m
} kxRV)G
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CountCache.java ow#1="G,=
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/* +U.I( 83F
* CountCache.java 7!$^r$t
* -tNUMi'
* Created on 2007年1月1日, 下午5:01 F3N6{ysK#
* d:{O\
* To change this template, choose Tools | Options and locate the template under e!r-+.i(
* the Source Creation and Management node. Right-click the template and choose VQ{fne<
* Open. You can then make changes to the template in the Source Editor. +'@Dz9:>
*/ ^BL"wk
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package com.tot.count; FEVlZ<PW3I
import java.util.*; Wr5V`sM
/** p6WX9\qS(
* #!m.!?
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* @author xp9pl[l
*/ uOGw9O-d9
public class CountCache { GDy9qUV
public static LinkedList list=new LinkedList(); \B
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/** Creates a new instance of CountCache */ i2^>vYCsl
public CountCache() {} Ip]KPrwp
public static void add(CountBean cb){ Zr,VR-kW+
if(cb!=null){ y#$CMf
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list.add(cb);
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} ++#5
} .y,0[i V
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} ~| 6[j<ziL
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CountControl.java WSY}d
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/* SC])?h-Fw
* CountThread.java 9!DQ~k%
* V,?yPi$#E
* Created on 2007年1月1日, 下午4:57 -FlzEZ
* "2T#MO/
* To change this template, choose Tools | Options and locate the template under bnLPlf
* the Source Creation and Management node. Right-click the template and choose 7(
2{'r
* Open. You can then make changes to the template in the Source Editor. Y7[jqb1D
*/ -\n@%$M]G
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package com.tot.count; _H=Uwi_g
import tot.db.DBUtils; ~BkCp pI
import java.sql.*; g
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/** U~l$\c
* '!a'ZjYyi
* @author d$AWu{y
*/ 5-xX8-ElYz
public class CountControl{ .%C|+#&d
private static long lastExecuteTime=0;//上次更新时间 mS~kJy_-
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 /_#q@r4ZQ
/** Creates a new instance of CountThread */ 6qd\)q6T&x
public CountControl() {} QZ%`/\(!8_
public synchronized void executeUpdate(){ H1(Uw:V8
Connection conn=null; q\527^ZM
PreparedStatement ps=null; LAe6`foW/
try{ Sa`Xf\
conn = DBUtils.getConnection(); v2;`f+
conn.setAutoCommit(false); ,T8 ~L#M~
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); nmi|\mof
for(int i=0;i<CountCache.list.size();i++){ N<KS(@v
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CountBean cb=(CountBean)CountCache.list.getFirst(); O|N{v"o
CountCache.list.removeFirst(); *~j@*{u
ps.setInt(1, cb.getCountId()); q,U+qt
ps.executeUpdate();⑴ f!
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//ps.addBatch();⑵ M>8A\;"
} %\Mo-Ow!\
//int [] counts = ps.executeBatch();⑶ 6;qy#\}2
conn.commit(); r s?R:+
}catch(Exception e){ Sw^u3
e.printStackTrace(); ~PahoRS
} finally{ \qK&q
try{ nSAdCJ;4
if(ps!=null) { wtV#l4
ps.clearParameters(); fCobzDy
ps.close(); g]yBA7/S"
ps=null; fG w9!
} 8d-t|HkN
}catch(SQLException e){} 1"M]3Kl
DBUtils.closeConnection(conn); :e%Pvk
} 1!T1Y,w
} YNj`W1
public long getLast(){ {9aE5kR
return lastExecuteTime; "djw>|,N<
} pK'V9fD5J
public void run(){ #7YY<)
xt}
long now = System.currentTimeMillis(); 5vZ^0yFQ
if ((now - lastExecuteTime) > executeSep) { ^7KH _t8
//System.out.print("lastExecuteTime:"+lastExecuteTime); g5QZ0Qkj
//System.out.print(" now:"+now+"\n"); x&T [*i
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); >:!X.TG$
lastExecuteTime=now; y(pks$
executeUpdate(); &wE%<"aRAl
} o\pVp bB
else{ TNh1hhJ$b
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); #PQB(=299P
} 8j\cL'
} \:ak ''
} z}ddqZ27G$
//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 `eCo~(Fy
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类写好了,下面是在JSP中如下调用。 $.rhRKs
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<% xJ)n4)
CountBean cb=new CountBean(); /j|G(vt5
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); .:QLk&a,:,
CountCache.add(cb); aL&7 1^R,
out.print(CountCache.list.size()+"<br>"); H_X [t* 2
CountControl c=new CountControl(); !XCm>]R
c.run(); xZwLlY
out.print(CountCache.list.size()+"<br>"); I \[_9
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