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: BpC Sf.zZ
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CountBean.java _H,RcpyJ
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/* V;V9_qP,
* CountData.java \5Jv;gc\\
* p.HA`R>
* Created on 2007年1月1日, 下午4:44 `#ztp)&
* ~IXfID!8
* To change this template, choose Tools | Options and locate the template under jt3SA
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* the Source Creation and Management node. Right-click the template and choose x#^kv)
* Open. You can then make changes to the template in the Source Editor. OrBFe *2y
*/ c>g%oE
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package com.tot.count; 6PH*]#PfoD
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/** j7d;1 zB+G
* D.!4i.)8}
* @author 9V&LJhDQ
*/ N9Ml&*%oX{
public class CountBean { [h1{{Nb#ez
private String countType; ?]z
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int countId; 9 2EMDKJ
/** Creates a new instance of CountData */ -&?-
public CountBean() {} KkY22_{ac
public void setCountType(String countTypes){ eBB
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this.countType=countTypes; Ir'f((8:
} (0+m&,
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public void setCountId(int countIds){ a|NU)mgEI
this.countId=countIds; iCS/~[
} H]e 2d|
public String getCountType(){ riL!]'akV
return countType; |#wz)=mD
} [xPE?OD
public int getCountId(){ A@ME7^w7
return countId; if'4MDl
} H/$q]i*#K
} *"ShE=\p
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CountCache.java gUp0RPs
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/* 'UxA8i(
* CountCache.java 0"`skYJ@
* ;qMlGXW*q
* Created on 2007年1月1日, 下午5:01 V'.|IuN
* pB./L&h
* To change this template, choose Tools | Options and locate the template under brWt
* the Source Creation and Management node. Right-click the template and choose =S,<yQJ
* Open. You can then make changes to the template in the Source Editor. 9o`3g@6z
*/ u W T[6R
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package com.tot.count; H~Cfni;
import java.util.*; ^=G+]$ 8
/** KfNXX>'
* F!{SeH:
* @author ;"Y6&YP<
*/ ;[9Is\
public class CountCache { 4lCm(#T{,
public static LinkedList list=new LinkedList(); 7Cf(y'w^
/** Creates a new instance of CountCache */ bSLj-vp
public CountCache() {} AHGcWS\,X
public static void add(CountBean cb){ R{vPn8X6g
if(cb!=null){ 8H?AL
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list.add(cb); B5G$o{WM
} }^7V^W
} /3]|B%W9
} h.0K
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CountControl.java 1tW:(~=a;
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/* 7w, FA
* CountThread.java L ]c9
* S)yV51^B
* Created on 2007年1月1日, 下午4:57 ]||=<!^kn
* 'QF>e
* To change this template, choose Tools | Options and locate the template under Vi WgX.
* the Source Creation and Management node. Right-click the template and choose :8rCCop
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* Open. You can then make changes to the template in the Source Editor. OWsYE?
*/ #9OP.4
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package com.tot.count; t;Om9
import tot.db.DBUtils; Z >=Y
import java.sql.*; ,6"n5Ks}
/** 98^6{p
* "'Uk0>d=_I
* @author B:cOcd?p
*/ fx:KH:q3
public class CountControl{ 6l'y
private static long lastExecuteTime=0;//上次更新时间 h>0<@UP
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 %<yM=1~>
/** Creates a new instance of CountThread */ M7,MxwZ0k
public CountControl() {} >N-%
public synchronized void executeUpdate(){ "6Uj:9
Connection conn=null; i5Q<~;Z+
PreparedStatement ps=null; zi
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try{ 0(x@
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conn = DBUtils.getConnection(); yan[{h]EZ
conn.setAutoCommit(false); _#mqg]W '
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); bq-\'h
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for(int i=0;i<CountCache.list.size();i++){ :* b4/qpYv
CountBean cb=(CountBean)CountCache.list.getFirst(); =fK'Ep[
CountCache.list.removeFirst(); om?CFl
ps.setInt(1, cb.getCountId()); ~-wJ#E3g
ps.executeUpdate();⑴ X:&p9_O@
//ps.addBatch();⑵ lVtn$frp
} q}Z
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//int [] counts = ps.executeBatch();⑶ ]xEE7H]\h
conn.commit(); yuEOQ\!(u
}catch(Exception e){ p]Zabky
e.printStackTrace(); tY'QQN||
} finally{ #%b()I_([
try{ XS8~jBjx
if(ps!=null) { j9'XZq}
ps.clearParameters(); yMl'1W
ps.close(); )O C[;>F7
ps=null; 3z92Gy5cr
} Eu.qA9,@U
}catch(SQLException e){} @H0%N53nE
DBUtils.closeConnection(conn); #l# [\6
} MmH_gR
} KxmPL
public long getLast(){ fMPq
return lastExecuteTime; Q0Qm0B5eY
} j%jd@z ]@
public void run(){ myOX:K*
long now = System.currentTimeMillis(); v9lBk]c
if ((now - lastExecuteTime) > executeSep) { o~_>p/7;
//System.out.print("lastExecuteTime:"+lastExecuteTime); 5'Jh2r
//System.out.print(" now:"+now+"\n"); N('DIi*or
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ,9wenr
lastExecuteTime=now; R(N(@KC
executeUpdate(); l~TIFmHkh%
} Ej09RO"pB
else{ 5|G3t`$pa
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); sJK:xk.6!
} (Zg'pSs)
} y6jmn1K
} gzCMJ<3!D
//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
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类写好了,下面是在JSP中如下调用。 Bye@5D
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<% tW"ptU^9)
CountBean cb=new CountBean(); 1idjX"'
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); CU1\C*
CountCache.add(cb); wU)5Evp[
out.print(CountCache.list.size()+"<br>"); ]!G>8Rc
CountControl c=new CountControl(); <` j[;>O
c.run(); A2:){`Mw
out.print(CountCache.list.size()+"<br>"); .4re0:V
%>