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: ;?h+8Z/{
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CountBean.java )6!ji]c
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/* 7.mYzl-F(
* CountData.java 9Sey&x
* If>bE!_BO
* Created on 2007年1月1日, 下午4:44 Mg"e$m
* ,1K`w:uhS
* To change this template, choose Tools | Options and locate the template under _O,k0O
* the Source Creation and Management node. Right-click the template and choose <%Al(Lm0
* Open. You can then make changes to the template in the Source Editor. gJ=y7yX
*/ W1;QPdz:
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package com.tot.count; 5^5hhm4
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/** -){aBMOv3
* J@}PBHK+
* @author 0s$;3qE
*/ <u_vL
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public class CountBean { h_>DcVNIx
private String countType; .ZtW
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int countId; JGHQzC
/** Creates a new instance of CountData */ Ndz'^c
public CountBean() {} 73p7]Uo
public void setCountType(String countTypes){ jLM}hwJ8
this.countType=countTypes; ieap
} UdOO+Z_K%
public void setCountId(int countIds){ >vPv4e7&3
this.countId=countIds; Ee3-oHa
}
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public String getCountType(){ 4JO[yN
return countType; +\R__tx;
} BjyV&1tRV!
public int getCountId(){ B&+)s5hh
return countId; ;F;Vm$
} =]fOQN`
} $TX]*hNn
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CountCache.java BUs={"Pa
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/* Z mc"
* CountCache.java 3\ {?L
* J kxsua
* Created on 2007年1月1日, 下午5:01 .<zN/&MXf
* z -c1,GOD
* To change this template, choose Tools | Options and locate the template under C=Tq/L w
* the Source Creation and Management node. Right-click the template and choose ?={S"qK(q
* Open. You can then make changes to the template in the Source Editor. ZOBcV,K
*/ ipe8U1Sc
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package com.tot.count; '
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import java.util.*; dK Qu
/** AM0CIRX$
* 6_L<&RmLg
* @author ^WkqRs
*/ nB;[;dCz
public class CountCache { &+]-e;[
public static LinkedList list=new LinkedList(); /# d^
/** Creates a new instance of CountCache */ 9$#@Oe8*
public CountCache() {} ]++,7Z\AU
public static void add(CountBean cb){ ,m Nd#
if(cb!=null){ d{Cg3v` Rd
list.add(cb); 9|WV28PK:
} ][dst@?8Oz
} Alk+MwjR
} `t"7[Zk
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CountControl.java cE^Ljk
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/* tIT/HG_o
* CountThread.java d=0{vsrB
*
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* Created on 2007年1月1日, 下午4:57 jf.WmiDC
* w\RYxu?
* To change this template, choose Tools | Options and locate the template under P=aYwm C
* the Source Creation and Management node. Right-click the template and choose TbD
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* Open. You can then make changes to the template in the Source Editor. d%K&
*/ VXnWY8\
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package com.tot.count; t2Px?S?
import tot.db.DBUtils; TQtHU6
import java.sql.*; wBJ|%mc3TA
/** R"yxpw
* \fsNI T/
* @author ;@*<M\O
*/ ;\(LovUy6
public class CountControl{ CofTTYl
private static long lastExecuteTime=0;//上次更新时间 3a[ LM!
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 dZY|6
/** Creates a new instance of CountThread */ rJ{k1H >
public CountControl() {} Kk,u{EA
public synchronized void executeUpdate(){ R=3|(R+kA
Connection conn=null; +Ks 3
PreparedStatement ps=null; "rrw~
try{ )KY4BBc
conn = DBUtils.getConnection(); t`Rbn{
conn.setAutoCommit(false); `GSl}A
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); qu\U^F
for(int i=0;i<CountCache.list.size();i++){ h$#PboLd
CountBean cb=(CountBean)CountCache.list.getFirst(); 1En:QQ4/
CountCache.list.removeFirst(); UIkO_/}
ps.setInt(1, cb.getCountId()); *a^wYWa
ps.executeUpdate();⑴ <iBn-EG l>
//ps.addBatch();⑵ `oTV)J'~
} CTe!jMZ=
//int [] counts = ps.executeBatch();⑶ }qJ`nN8
conn.commit(); /BN=Kl]
}catch(Exception e){ J/QqwoR
e.printStackTrace(); <J>k%,:B
} finally{ kRr/x-"
try{ !ALq?u
if(ps!=null) { O6,2M[a
ps.clearParameters(); ,vo]WIQ\:
ps.close(); bk1.H@8
ps=null; yFn~rv|&G
} ILx4[m7
}catch(SQLException e){} )%b 5uZ
DBUtils.closeConnection(conn); K^h9\<w
} [&IcIZ
} (+6N)9rj`/
public long getLast(){ VN0KK
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return lastExecuteTime; ^ZIs >.'
} +^jm_+
public void run(){ Rt7l`|g a+
long now = System.currentTimeMillis(); (Y*9[hm
if ((now - lastExecuteTime) > executeSep) { -Mf-8zw8G
//System.out.print("lastExecuteTime:"+lastExecuteTime); w5yX~8UzJ
//System.out.print(" now:"+now+"\n"); 0|]d^bo
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); LqXVi80
lastExecuteTime=now; 3<l}gB'S[
executeUpdate(); ]9~Il#
} P+y XC^ ,
else{ \mTi@T!&
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); da~_(giD*
} ^G 'n
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} ,xR u74
} ~Q#!oh'i
//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 H )>3c1
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类写好了,下面是在JSP中如下调用。 _#Lq~02 %
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<% N]14~r=
CountBean cb=new CountBean(); ,c0t#KgQ.
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); E3(o}O
CountCache.add(cb); Vc6
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out.print(CountCache.list.size()+"<br>"); +*Fe
CountControl c=new CountControl(); D>^g2!b:
c.run(); EM@EB<pRX
out.print(CountCache.list.size()+"<br>"); H!6+x*P0
%>