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: i]8zZRe
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CountBean.java P/M*XUG.
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/* *!C^L"i
* CountData.java Vi5RkUY]
*
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* Created on 2007年1月1日, 下午4:44 "=P@x|I
* #FTXy>W
* To change this template, choose Tools | Options and locate the template under M={k4r_t
* the Source Creation and Management node. Right-click the template and choose <:RU,
* Open. You can then make changes to the template in the Source Editor. NFmB ^@k
*/ ]=@>;yP)
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package com.tot.count; XImb"7|
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/** qI8{JcFx:
* xCoQ>.4p
* @author ]%>;R^HY
*/ -_b}b)2iYN
public class CountBean { 42Kzdo|}
private String countType; BO/2kL8*
int countId; R4@C>\c%m
/** Creates a new instance of CountData */ R^%7|
public CountBean() {} NBUM* Z
public void setCountType(String countTypes){ \iu2rat^
this.countType=countTypes; t)$>++i
} {{@3r5KGl
public void setCountId(int countIds){ cN&b$8O=%
this.countId=countIds; y$4,r4cmR|
} L.+5`&
public String getCountType(){ K
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return countType; Xps MgJ/w
} bG2!5m4L
public int getCountId(){ 7v%~^l7:x
return countId; "b-6kM
} R:^GNra;
} b4oZ@gVR;
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CountCache.java X1tAV>k5'L
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/* h+N75
* CountCache.java $Iqt
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* T][\wyLx1
* Created on 2007年1月1日, 下午5:01 Q\ro )r
* ==UH)o`?8
* To change this template, choose Tools | Options and locate the template under 2&Wc4,O!i
* the Source Creation and Management node. Right-click the template and choose qI5/ME(}
* Open. You can then make changes to the template in the Source Editor. -!wm]kx
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*/ * k=Pk
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package com.tot.count; ]%shs
import java.util.*; 3&x_%R
/** @kI^6(.
* 5hg>2?e9s?
* @author -kQ{~">w
*/ h'IBVI!P
public class CountCache { ph^qQDA
public static LinkedList list=new LinkedList(); B-r9\fi,
/** Creates a new instance of CountCache */ r95$B6
public CountCache() {} 4v E,nx=
public static void add(CountBean cb){ D/@:wY
if(cb!=null){ E
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list.add(cb); X Uh)z
} O6k[1C
} HZfcLDrO
} YBHmd
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CountControl.java :R<,J=+$u
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/* 8c]\4iau
* CountThread.java >UR-37g{p
* "qQU ^FW
* Created on 2007年1月1日, 下午4:57 aViJ?*
* $~ zqt%}
* To change this template, choose Tools | Options and locate the template under r(i<H%"Z
* the Source Creation and Management node. Right-click the template and choose A+;]# 1y(D
* Open. You can then make changes to the template in the Source Editor.
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*/ 1c?,= ;>
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package com.tot.count; >{npg2
import tot.db.DBUtils; TtKBok
import java.sql.*; vEn12s(lj
/** qX-Jpi P
* So0YvhZ+
* @author r{6 ,;
*/ T5W r;a
public class CountControl{ IxgnZX4N
private static long lastExecuteTime=0;//上次更新时间 t2tH%%Rs
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 |$7!u DU8
/** Creates a new instance of CountThread */ -D{~7&
public CountControl() {}
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public synchronized void executeUpdate(){ KC8A22
Connection conn=null; Tje =vI
PreparedStatement ps=null; H-7*)D
try{ lE=Q(QUr
conn = DBUtils.getConnection(); ^>[DG]g
conn.setAutoCommit(false); q&
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ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); t(Iy[-
for(int i=0;i<CountCache.list.size();i++){ \!z=x#!O$
CountBean cb=(CountBean)CountCache.list.getFirst(); :vX;>SH$p
CountCache.list.removeFirst(); G0y%_"[
ps.setInt(1, cb.getCountId()); B^$l]cvZ
ps.executeUpdate();⑴ ?#slg8[
//ps.addBatch();⑵ jVk|(
} ^x:4%%Q]l
//int [] counts = ps.executeBatch();⑶ mxGvhkj
conn.commit(); o.}^6.h"
}catch(Exception e){ &&JI$x0;
e.printStackTrace(); |WubIj*\{
} finally{ ?ix0n,m
try{ D.R5-
if(ps!=null) { [9aaHf@'
ps.clearParameters(); /KlA7MH 6
ps.close(); .- c3f1i
ps=null; z9;vE7n!
} P]r"E
}catch(SQLException e){} zXUE<\
DBUtils.closeConnection(conn); *b7HtUA
} dpJi5fN
} Mr/^V,rA
public long getLast(){ 5
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return lastExecuteTime; JL;H :`x
} 3=sA]j-+(
public void run(){ k 2;m"F
long now = System.currentTimeMillis(); A 7DdU NR
if ((now - lastExecuteTime) > executeSep) { l_^>spF
//System.out.print("lastExecuteTime:"+lastExecuteTime); Me5umA
//System.out.print(" now:"+now+"\n"); Pgye{{
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ;@v7AF6Hq
lastExecuteTime=now; *M-.Vor?R
executeUpdate(); owYfrf3ZLX
} >Z<ym|(T*
else{ |mY<TWoX
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); &WvJg#f
} '#u2q=n4*
} bis/Nfr]
} cr,o<
//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 E3NYUHfZ
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类写好了,下面是在JSP中如下调用。 [h8F)
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<% _2f}WY3S
CountBean cb=new CountBean(); 8a.
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); T7cT4PAW
CountCache.add(cb); =CRaMjN
out.print(CountCache.list.size()+"<br>"); B;W=61d
CountControl c=new CountControl(); e/@udau
c.run(); Yn1 U@!
out.print(CountCache.list.size()+"<br>"); \EB]J\x<
%>