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: IM9P5?kJ
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CountBean.java F|{F'UXj|
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/* B#Z-kFn@
* CountData.java 'Bb@K[=s
* /woC{J)4p
* Created on 2007年1月1日, 下午4:44 2#g4R
* 8jz[;.jP",
* To change this template, choose Tools | Options and locate the template under 9d1 Gu"
* the Source Creation and Management node. Right-click the template and choose ~u+|NtF
* Open. You can then make changes to the template in the Source Editor. #uHl
*/ |cd=7[B
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package com.tot.count; os~}5QJ
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/** kF o&!
* @#W$7Gwf0
* @author H]d'#1G
*/ k=8L hO
public class CountBean { KuohUH+
private String countType; j+7ok 5J#
int countId; ?)V}_%fVv
/** Creates a new instance of CountData */ _rjLCvv-
public CountBean() {} O| zLD
public void setCountType(String countTypes){ xzjG|"a[GB
this.countType=countTypes; v'W`\MKY)
} o YNp0Hc
public void setCountId(int countIds){ $dgez#TPL
this.countId=countIds; 08JVX'X-mr
} y.m;4((
public String getCountType(){ i1JWdHt
return countType; xPJ
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} vspub^;5\
public int getCountId(){ 8
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return countId;
}j /r
} '-k~qQk)6
} ?B`Yq\L)
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CountCache.java Yt%
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/* 4hh=z>$|l)
* CountCache.java O)i]K`jk
* b/dyH
* Created on 2007年1月1日, 下午5:01 06peo
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* BpQ/$?5E"
* To change this template, choose Tools | Options and locate the template under 875BD U
* the Source Creation and Management node. Right-click the template and choose (!9ybH;T
* Open. You can then make changes to the template in the Source Editor. 0;pO QF
*/ ^S'tMT_
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package com.tot.count; EFKOElG(k
import java.util.*; 70&]nb6f
/** ]\_T
* en6oFPG
* @author L4,Ke
*/ 5{uK;Vxse
public class CountCache { 7/$s!pV
public static LinkedList list=new LinkedList(); A"8"e*
/** Creates a new instance of CountCache */ rt7]~W-
public CountCache() {} d3| oKP6
public static void add(CountBean cb){ E?+MM0
if(cb!=null){ Q]]5\C.
list.add(cb); &QQ8ut,;
} ;
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} |vY0[#E8&
} d|8iD`sZz
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CountControl.java i`2X[kc
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/* 0 w#[?.
* CountThread.java 30Z RKrW"~
* &R
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* Created on 2007年1月1日, 下午4:57 A+Xk=k5<
* #=hI}%n
* To change this template, choose Tools | Options and locate the template under $SmmrM
* the Source Creation and Management node. Right-click the template and choose =1}Umn|ZLS
* Open. You can then make changes to the template in the Source Editor. 7>`VZ?
*/ g,
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package com.tot.count; Ka"Z,\T
import tot.db.DBUtils; xXktMlI
import java.sql.*; +s'qcC
/** iS"(
*
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* @author NHCdf*
*/ -OS&(7
public class CountControl{ k'K&GF1B
private static long lastExecuteTime=0;//上次更新时间 '`*{ig
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 AShnCL8uR
/** Creates a new instance of CountThread */ a|x1aN0
public CountControl() {} !L#>wlX)
public synchronized void executeUpdate(){ 1*"t-+|
Connection conn=null; -&ic%0|f
PreparedStatement ps=null; rK\)
try{ URodvyD
conn = DBUtils.getConnection(); t
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conn.setAutoCommit(false); jB17]OCN
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); H-sJt:
for(int i=0;i<CountCache.list.size();i++){ %dMP}k/
CountBean cb=(CountBean)CountCache.list.getFirst(); #iOoi9(
CountCache.list.removeFirst(); BF_R8H,<%
ps.setInt(1, cb.getCountId()); :|:Disg
ps.executeUpdate();⑴ -H3tBEvoI
//ps.addBatch();⑵ hK,e<?N^
} xnW3,:0
//int [] counts = ps.executeBatch();⑶ V2I"m
conn.commit(); 4Em mh=A
}catch(Exception e){ X&[S.$_U
e.printStackTrace(); na&?Cw
} finally{ AAr[xoiYp
try{ =Kv*M@
if(ps!=null) { PSO9{!
ps.clearParameters(); >h0iq
ps.close(); R`wL%I!?f
ps=null; pb(YA/
} 3U<\s=1?X
}catch(SQLException e){} &;%z1b>F
DBUtils.closeConnection(conn); o
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} <#s=78
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} L*Mt/
public long getLast(){ Nd.+Rs
return lastExecuteTime; gJ_{V;R
} /R@,c
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public void run(){ GnlP#;
long now = System.currentTimeMillis(); =""z!%j
if ((now - lastExecuteTime) > executeSep) { P9)E1]Dc$
//System.out.print("lastExecuteTime:"+lastExecuteTime); Z.b}
//System.out.print(" now:"+now+"\n"); P,x'1`k~
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); )x/Spb
lastExecuteTime=now; UJXRL
executeUpdate(); p9;Oe,Il
} }dl[~iKW
else{ G6C#M-S
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); E|t.
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} 5U&b")3IT!
} oh
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} i(^&ZmG
//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 kCXQHX
I+,~pmn:
类写好了,下面是在JSP中如下调用。 v`"z
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<% O\h*?, )
CountBean cb=new CountBean(); /Q4TQ\:
cb.setCountId(Integer.parseInt(request.getParameter("cid")));
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CountCache.add(cb); j~(s3pSCo
out.print(CountCache.list.size()+"<br>"); _;G. QwHr
CountControl c=new CountControl(); ,9I %t%sb
c.run(); #,0PLU3%
out.print(CountCache.list.size()+"<br>"); YRXXutm
%>