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: H1 n`A#6?
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CountBean.java pHni"iT
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/* h?bm1e5kE
* CountData.java e}(ws~.
* %1@+pf/
* Created on 2007年1月1日, 下午4:44 GasIOPzK
* 0>Z/3i&?<
* To change this template, choose Tools | Options and locate the template under b0tr)>d
* the Source Creation and Management node. Right-click the template and choose h/V0}|b
* Open. You can then make changes to the template in the Source Editor. ~${.sD\
*/ KxGK`'E'r
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package com.tot.count; f`RcfYt
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/** r?\hZ* |M
* @wYuc{%S
* @author t{Q9Kv
*/ #";(&|7
public class CountBean { FX+Ra@I!
private String countType; HMS9_#[kE
int countId; 72&xEx
/** Creates a new instance of CountData */ KFLIO>hE
public CountBean() {} F,P,dc
public void setCountType(String countTypes){ )e4nKh],
this.countType=countTypes; `+\+
} :a0qm.EN
public void setCountId(int countIds){ hCc_+/j|
this.countId=countIds; CcLP/
} x>!#8?-h
public String getCountType(){ n$axqvG
return countType; PLw;9^<
} p(v+j_ak
public int getCountId(){ 6S2D\Bt,_
return countId; *'QD!Tc
} @Ej{sC!0T
} z./u;/:
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CountCache.java F[l{pc "C
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/* #QXB2x<*
* CountCache.java elJLTG
* (Y)$+9
* Created on 2007年1月1日, 下午5:01 lmp0Ye|
* mmu{K$9}I
* To change this template, choose Tools | Options and locate the template under ORA+>
* the Source Creation and Management node. Right-click the template and choose @L=xY[&{
* Open. You can then make changes to the template in the Source Editor. ZvkO#j
*/
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package com.tot.count; !n}"D:L(
import java.util.*; Qg%B<3 <
/** R8W{[@
* hof:36 <
* @author |jU/R
*/ egYJ.ZzF0
public class CountCache { b=wc-nA
public static LinkedList list=new LinkedList(); J3oH^
/** Creates a new instance of CountCache */ u0A.I_
public CountCache() {} TC<_I0jCh
public static void add(CountBean cb){ y7u"a)T
if(cb!=null){
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list.add(cb); 2Vr F~+
} A]WU*GL2H
} Zyu4!
} :;#^h]Q
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CountControl.java nkG1&wiX
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/* {<v?Z_!68
* CountThread.java 2h@/Q)z
* (ye1t96
* Created on 2007年1月1日, 下午4:57 Z0`Bn5
* ^{DXin 1O`
* To change this template, choose Tools | Options and locate the template under sPyq.oG
* the Source Creation and Management node. Right-click the template and choose _Q t
* Open. You can then make changes to the template in the Source Editor. VWj]X7v
*/ &j<B22t!
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package com.tot.count; ,j:`yB]4,
import tot.db.DBUtils; 0/6f9A
import java.sql.*; yrSmI)&%
/** Z]@my,+Z;
* ey _3ah3x
* @author nVoL7ew+
*/ QgqR93Ic
public class CountControl{ dAh&Z:86\
private static long lastExecuteTime=0;//上次更新时间 `k+ci7;
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 `1=n H/E
/** Creates a new instance of CountThread */ H!y1&
public CountControl() {} _rdEur C6
public synchronized void executeUpdate(){ @>}!g9c
Connection conn=null; \xlelsmB*
PreparedStatement ps=null; ]]Sz|6 P
try{ Sp]"Xr)
conn = DBUtils.getConnection(); ,,sKPj[
conn.setAutoCommit(false); 6U Q~Fv`]
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ,6=j'j1#a
for(int i=0;i<CountCache.list.size();i++){ M2W4 RovfR
CountBean cb=(CountBean)CountCache.list.getFirst(); z\]]d?d?;
CountCache.list.removeFirst(); _ho9}7 >
ps.setInt(1, cb.getCountId()); :XC~G&HuF6
ps.executeUpdate();⑴ 9. 6"C<eYt
//ps.addBatch();⑵ p[2`H$A
} F0qpJM,
//int [] counts = ps.executeBatch();⑶ y'((
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conn.commit(); ;.Zgt8/.
}catch(Exception e){ "oz
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e.printStackTrace(); T`mG+"O
} finally{ +DmfqKKbd
try{ 6!sC
if(ps!=null) { _ I"}3*
ps.clearParameters(); fd!bs*\X
ps.close(); s1.EE|h,5
ps=null; `$*I%oT;
} [3lAKI
}catch(SQLException e){} <tXk\cOg
DBUtils.closeConnection(conn); t1}R#NB
} Q"7vzri
} C jISU$O
public long getLast(){ $9YAq/#Q
return lastExecuteTime; .)59*'0
} ,P ~jO
public void run(){ 'i+j;.
long now = System.currentTimeMillis(); p{X?_ F
if ((now - lastExecuteTime) > executeSep) { #
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//System.out.print("lastExecuteTime:"+lastExecuteTime); )l g>'O
//System.out.print(" now:"+now+"\n"); +txFdc
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); `v?XFwnV`
lastExecuteTime=now; UR?biq
executeUpdate(); ;l`us
} 6Ck 3tCr
else{ %;/?DQU
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); eocq Hwbv
} Iz^h|
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} 6i'GM`>w
} o1lhVM`15
//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 Y\75cfD
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类写好了,下面是在JSP中如下调用。 lt08
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^% ZbjJ7|j
<% dyWj+N5(
CountBean cb=new CountBean(); q> |&u
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); "QSmxr
CountCache.add(cb); /M!b3bmA
out.print(CountCache.list.size()+"<br>"); qQjd@J}^
CountControl c=new CountControl(); $0 ]xeD0X
c.run(); >vQ8~*xd
out.print(CountCache.list.size()+"<br>"); .JCd:'-
%>