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: b-2pzcK{#
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CountBean.java b/z'`?[
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/* y?"$(%3|
* CountData.java akMJ4EF/
*
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* Created on 2007年1月1日, 下午4:44 x!OWJ/O
* EG%I1F%
* To change this template, choose Tools | Options and locate the template under mZ]P[lQ'5
* the Source Creation and Management node. Right-click the template and choose ?n2C
* Open. You can then make changes to the template in the Source Editor. *3!(*F@M,
*/ X{#bJ
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package com.tot.count; 9z+vFk`
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/** JIVo=5c}
* +I*k0"gj6
* @author h]<GTWj
*/ _cR6ik zW(
public class CountBean { Ad^dF'SN
private String countType; Pa3{Ds
int countId; I+*osk
/** Creates a new instance of CountData */ B^H4Q
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public CountBean() {} j'\>Nn+
public void setCountType(String countTypes){ !&qx7eOSpP
this.countType=countTypes; &Q2NU$
} yVT&rQ"{
public void setCountId(int countIds){ Um/CR!
this.countId=countIds; ]gb _Nv
} +8]W\<Kp
public String getCountType(){ }*0,>w>
return countType; x6"/z
} 1aBD^^Y
public int getCountId(){ GVeL~Q
return countId; 4s[`yV
} \)FeuLGL9
} 7F,07\c
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CountCache.java ixIh
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/* dz{#"No0
* CountCache.java Ii|uGxEc
* pTc$+Z73
* Created on 2007年1月1日, 下午5:01 #E*@/ p/
* nUiS<D2
* To change this template, choose Tools | Options and locate the template under 8w03{H
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* the Source Creation and Management node. Right-click the template and choose O5g}2
* Open. You can then make changes to the template in the Source Editor. SL6mNn9c
*/ Xq+!eOT
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package com.tot.count; 2O?Vr"
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import java.util.*; g7.7E6%H
/** =n> iQS
* 3X,]=f@_
* @author H0: iYHu
*/ np<f,
public class CountCache { es.jh
public static LinkedList list=new LinkedList(); E~'q?LJOB
/** Creates a new instance of CountCache */ 1,m\Q_
public CountCache() {} kJHr&=VO~
public static void add(CountBean cb){ U*
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if(cb!=null){ `2Wl
list.add(cb); >L#];|
} 3 %z
} H|grbTv,
} &mX5&e
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CountControl.java /p[|DJoM
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/* AQE
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* CountThread.java Y'tq m&}
* 6XQ*:N/4al
* Created on 2007年1月1日, 下午4:57 WAtg
* j9{O0[v
* To change this template, choose Tools | Options and locate the template under ^>3tYg&7
* the Source Creation and Management node. Right-click the template and choose L4MxU 2
* Open. You can then make changes to the template in the Source Editor. $ \? N<W
*/ x, G6\QmA
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package com.tot.count; qzuQq94k
import tot.db.DBUtils; pWWL{@ J
import java.sql.*; A~qW.
/** qFvg}}^y
* ~5lKL5w
* @author _<u8%\
*/ vpZu.#5c
public class CountControl{ 1"8Z
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private static long lastExecuteTime=0;//上次更新时间 `4q5CJ2
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 43vGgGW
/** Creates a new instance of CountThread */ M'pb8jf
public CountControl() {} ap Fs UsE
public synchronized void executeUpdate(){ *ge].E
Connection conn=null; ^+(A&PyP?
PreparedStatement ps=null; *>H M$.?Q
try{ r]8wOu-'
conn = DBUtils.getConnection(); Q%M'[L?[
conn.setAutoCommit(false); + ")qi=
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); {DKXn`V
for(int i=0;i<CountCache.list.size();i++){ <C7M";54-
CountBean cb=(CountBean)CountCache.list.getFirst(); 5*s1qA0^
CountCache.list.removeFirst(); sN}s61
ps.setInt(1, cb.getCountId()); <'PR;g^#
ps.executeUpdate();⑴ 2rK-X_}
//ps.addBatch();⑵ h
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} .8u$z`j
//int [] counts = ps.executeBatch();⑶ d$2@,
conn.commit(); [VY8?y
}catch(Exception e){ A)b)ff ,
e.printStackTrace(); tIz<+T_
} finally{ ig2{lEkF
try{
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if(ps!=null) { :FX'[7;p
ps.clearParameters(); +-Z"H)
ps.close(); OaD
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ps=null; #6Efev
} DFt=%aV[
}catch(SQLException e){} _hAj2%SL
DBUtils.closeConnection(conn); P!`Q_h6a
} c8bca`
} 7\7 Brw4
public long getLast(){ yt/20a
return lastExecuteTime; 6%\7.h
} .ujs`9d_-
public void run(){ \_*?R,$3Y,
long now = System.currentTimeMillis(); S5:"_U
if ((now - lastExecuteTime) > executeSep) { |i,zY{GI+2
//System.out.print("lastExecuteTime:"+lastExecuteTime); OqfhCNAY
//System.out.print(" now:"+now+"\n"); Bo\a
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); WUE)SVf
lastExecuteTime=now; ^kCk^D-Gz
executeUpdate(); 'Z*\1Ci
} u)q2YLK8
else{ e3yorQ][
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 5PPPd-'Z_
} g|&.v2 '
} J8sJ~FnUj
} J6*\>N5W
//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 {pcf;1^t
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类写好了,下面是在JSP中如下调用。 H(5S Kv5
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<% _~X8/p/Qh
CountBean cb=new CountBean(); B-y0;0
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); E%wV
CountCache.add(cb); n9<roH
out.print(CountCache.list.size()+"<br>"); dXA{+<!!
CountControl c=new CountControl(); Q%,o8E2~
c.run(); nZ2mEt
out.print(CountCache.list.size()+"<br>"); fWtb mUq
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