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: uQ)JC7b\
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CountBean.java 1sIy*z
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/* L5-T6CD
* CountData.java
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* RTPq8S"
* Created on 2007年1月1日, 下午4:44 ei+9G,
* !]{1h
* To change this template, choose Tools | Options and locate the template under uFm(R/V
* the Source Creation and Management node. Right-click the template and choose 'XZI{q2i
* Open. You can then make changes to the template in the Source Editor. A-Q{*{^#
*/ .pB8=_e:
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package com.tot.count; 0gwm gc/#
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/** ^\7 x5gO
* 2$SofG6D}
* @author ]RJb;
*/ `Q1WVd29
public class CountBean { q{9X.-]}
private String countType; lgv-)5|O+H
int countId; Kc2OLz#
/** Creates a new instance of CountData */ $ +GFOO
public CountBean() {} @^y?Bh9jQ
public void setCountType(String countTypes){ 9rpg1 0/T
this.countType=countTypes; He0N
} `\RX~ $^
public void setCountId(int countIds){ 7 BnenHD
this.countId=countIds; 0]h8)EW
} Y?&DEKFbD
public String getCountType(){ &0th1-OP_
return countType; 4mM2C`I
}
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public int getCountId(){ c5wkzY h
return countId; 3gV&`>@
} 5Sm 5jRr
} T je o*n^
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CountCache.java IQk#
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/* H.l,%x&K
* CountCache.java 4B3irHs\Q
* v8U1uOR,%
* Created on 2007年1月1日, 下午5:01 qUDz(bFk/
* TsFdy{/o*
* To change this template, choose Tools | Options and locate the template under z[KN^2YS
* the Source Creation and Management node. Right-click the template and choose qUoMg%Z%l
* Open. You can then make changes to the template in the Source Editor. V&4:nIS>z
*/ Kl46CZs#8
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package com.tot.count; }!Diai*C
import java.util.*; mSk :7ozZ
/** v]`A_)[
* aG8D%i0
* @author q563,s
*/ &JXHDpd$a^
public class CountCache { U>plv
public static LinkedList list=new LinkedList(); xvx\H'
/** Creates a new instance of CountCache */ g+KzlS[6
public CountCache() {} Rbj+P;t&
public static void add(CountBean cb){ Kt4\&l-De
if(cb!=null){ CyK$XDHa
list.add(cb); w
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} +/b4@B7
} A9qO2kq7_
} \9|]
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CountControl.java $*v 20
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/* 8SCW.;0
* CountThread.java PkCeV]`w
* Zs5I?R1e8
* Created on 2007年1月1日, 下午4:57 CI~;B
* SJ~I
r#
* To change this template, choose Tools | Options and locate the template under =@Nv:1:r
* the Source Creation and Management node. Right-click the template and choose ^;k _
* Open. You can then make changes to the template in the Source Editor. l5y#i7 q
*/ DKVt8/vq
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package com.tot.count;
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import tot.db.DBUtils; R
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import java.sql.*; ?k:])^G5
/** hRy}G'0
* 'd.@4 9
* @author t0V_ c'm
*/ }DUDA%U
public class CountControl{ j]?0}Z*
private static long lastExecuteTime=0;//上次更新时间 PRk%C0`
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ^; V>}08
/** Creates a new instance of CountThread */ |YGiATD4DG
public CountControl() {} 76i
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public synchronized void executeUpdate(){ \(>$mtS:
Connection conn=null; 0rm;)[SjF
PreparedStatement ps=null; b
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try{ ;~@PYIp
conn = DBUtils.getConnection(); rIFC#Jd/
conn.setAutoCommit(false); }AsF\W+5
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); :D+SY
for(int i=0;i<CountCache.list.size();i++){ gJGBD9wC
CountBean cb=(CountBean)CountCache.list.getFirst(); nog\,NT
CountCache.list.removeFirst(); i{FC1tVeL_
ps.setInt(1, cb.getCountId()); + $a:X
ps.executeUpdate();⑴ Obc3^pV&
//ps.addBatch();⑵ Ae_ E;[mj
} 2-E71-J
//int [] counts = ps.executeBatch();⑶ {O&liU4
conn.commit(); dYqDL<se/I
}catch(Exception e){ hL{B9?
e.printStackTrace(); vK.4JOlRF
} finally{
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try{ -L 'K
if(ps!=null) { ~Yz/t
ps.clearParameters(); NdSxWrD`m
ps.close(); np\Q&
ps=null; tEX~72v
} e"adkV
}catch(SQLException e){} qM:)daS1w
DBUtils.closeConnection(conn); mV(x&`Cx
} :XQ
} YlcF-a
public long getLast(){ v3JIUdU=P
return lastExecuteTime; ^57fHlw
} cKYvRe
public void run(){ --%2=.X=
long now = System.currentTimeMillis(); 7n95>as
if ((now - lastExecuteTime) > executeSep) { IM5^E#-g7
//System.out.print("lastExecuteTime:"+lastExecuteTime); &'yV:g3H
//System.out.print(" now:"+now+"\n"); <[5$ {)
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); \HQb#f,
lastExecuteTime=now; *-!ndbf
executeUpdate(); WfbNar[
} W>|b98NPu
else{ t02"v4_i
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); l`%}
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} gcCYXPZp
} 6dy4{i
} )B&<Bk+
//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 ~\}EROb<
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类写好了,下面是在JSP中如下调用。 p;t!"I:`?
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<% pH:|G
CountBean cb=new CountBean(); &?`&X=Q
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); qf=[*ZY
CountCache.add(cb); pVa|o&,
out.print(CountCache.list.size()+"<br>"); +\Mm
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CountControl c=new CountControl(); fh)`kZDk
c.run(); n03SXaU~V
out.print(CountCache.list.size()+"<br>"); g5 |\G%dOt
%>