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: +20G>y=+
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CountBean.java 1v#%Ei$6`t
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/* Cwr~HY
* CountData.java XWnVgY s
* 5CuuG<0
* Created on 2007年1月1日, 下午4:44 C^s^D:
* ?llXd4
* To change this template, choose Tools | Options and locate the template under i|c'Lbre`
* the Source Creation and Management node. Right-click the template and choose U1Q:= yD
* Open. You can then make changes to the template in the Source Editor. T=<@]$?
*/ r=Gks=NX"
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package com.tot.count; #
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/** ^9m\=5d
* zofa-7'Bn
* @author 0;hqIJcE:\
*/ 90Pl$#cb2
public class CountBean { !1rlN8w(qr
private String countType; Gq+z /Be
int countId; WJ$bf(X*
/** Creates a new instance of CountData */ PvzcEV
public CountBean() {} LuNc,n%
public void setCountType(String countTypes){ i3dkYevs?
this.countType=countTypes; ]"r&]qx7
} q6@Lp^f
public void setCountId(int countIds){ \j+1V1t9
this.countId=countIds; *RDn0d[
} \4&fxe
public String getCountType(){ i=ea
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return countType; C](f>)Dz
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} j1^I+j)
public int getCountId(){ rT M}})81
return countId; :=}BN
} H[{F'c[e
} nR7d4)
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CountCache.java eds o2
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/* ?iPC*
* CountCache.java Q8C_9r/:N>
* |"?M 1*g
* Created on 2007年1月1日, 下午5:01 X]'{(?Ch
* BYpG
* To change this template, choose Tools | Options and locate the template under ;t'5},(FP
* the Source Creation and Management node. Right-click the template and choose , qA(\[
* Open. You can then make changes to the template in the Source Editor. ^.1)};i
*/ yGI;ye'U
#~#R-
package com.tot.count; ~F7-HaQJ
import java.util.*; _|iSF2f,X
/** KmMzH`t}`
* 1=t>HQ
* @author }]e-{C}
*/ d^Inb!%w
public class CountCache { u_hD}V^x4
public static LinkedList list=new LinkedList(); b+,';bW
/** Creates a new instance of CountCache */ .GV;+8HzS
public CountCache() {} zepm!JR1
public static void add(CountBean cb){ x%}^hiO<q
if(cb!=null){ ,">]`|?
list.add(cb); FFV `P
} U}& 2k
} 1jCLO}
} /rMI"khB
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CountControl.java 3)8QS
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/* io _1Y]N
* CountThread.java Ci?Ss+|
* t|a2;aq_
* Created on 2007年1月1日, 下午4:57 8u"!dq
* Vc_'hz]Z
* To change this template, choose Tools | Options and locate the template under 0vFD3}~>
* the Source Creation and Management node. Right-click the template and choose FQm`~rA~zt
* Open. You can then make changes to the template in the Source Editor. >go,K{cK6
*/ 7"aN#;&
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package com.tot.count; | 1E|hh@k
import tot.db.DBUtils; |s'Po^Sy
import java.sql.*; &atuK*W>
/** _
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* Lilr0|U+
* @author l%[EXZ
*/ ?6yjy<D)$e
public class CountControl{ YX=a#%vrl
private static long lastExecuteTime=0;//上次更新时间 kv3E4,<9
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 3_txg>P"
/** Creates a new instance of CountThread */ D6%J\C13`
public CountControl() {} c0PIc^R(@
public synchronized void executeUpdate(){ |*:'TKzNS
Connection conn=null; mX_a^_[G
PreparedStatement ps=null; ^.KwcXr
try{ ?>hPO73{
conn = DBUtils.getConnection(); ~kShq%
conn.setAutoCommit(false); Q(lo{AFc
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); K&bzDzd `
for(int i=0;i<CountCache.list.size();i++){ #,,d>e
CountBean cb=(CountBean)CountCache.list.getFirst(); [ad@*KFxy3
CountCache.list.removeFirst(); aAJU`=uq
ps.setInt(1, cb.getCountId()); J]v%q,"
ps.executeUpdate();⑴ aIJt0;
//ps.addBatch();⑵ ~5_Ad\n9
} pv*,gSS
//int [] counts = ps.executeBatch();⑶ W=vG$
conn.commit(); 6`O.!|)
}catch(Exception e){ hakKs.U|[
e.printStackTrace(); L0*nm.1X
} finally{ u\ #"L
try{ a&tSj35*6
if(ps!=null) { ]4~lYuI4
ps.clearParameters(); F5?m6`g?
ps.close(); 'd.EC#
ps=null; 5V6G=H
} ,u!*2cWN
}catch(SQLException e){} G;&-\0>W
DBUtils.closeConnection(conn); A9f)tqbc
} uxW~uEh
} >*]Hq.&8
public long getLast(){ WP?TX b`5
return lastExecuteTime; M4zm,>?K
} Ey_" ~OB
public void run(){ sp#p8@Cj
long now = System.currentTimeMillis(); e}Cif2#d~
if ((now - lastExecuteTime) > executeSep) { >ZPsjQuf"
//System.out.print("lastExecuteTime:"+lastExecuteTime); H$@`,{M629
//System.out.print(" now:"+now+"\n"); k40* e\
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); bvS(@
lastExecuteTime=now; \]%6|V
executeUpdate(); qDv93
} 9F4Dm*_<
else{ ,$+lFv3LE
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); /a^1_q-bX
} j/>$,
} }!;s.[y
} ?3%`bY+3;
//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 _9JhL:cY
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类写好了,下面是在JSP中如下调用。 N
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<% ~KW,kyXBnD
CountBean cb=new CountBean(); |UK}
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); K <pV
CountCache.add(cb); hCCiD9gz
out.print(CountCache.list.size()+"<br>"); 'qjeXqGH$
CountControl c=new CountControl(); p89wNSMl[
c.run(); m1),;RsH
out.print(CountCache.list.size()+"<br>"); WKT4D}{1
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