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: GOrDDp
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CountBean.java @{N2I$%6
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/* v;m`d{(i2
* CountData.java o81RD#>E)
* fy]z<SPhVJ
* Created on 2007年1月1日, 下午4:44 Bn:"qN~
* J<hqF4z
* To change this template, choose Tools | Options and locate the template under :/UO3 c(
* the Source Creation and Management node. Right-click the template and choose ko<u0SjF)u
* Open. You can then make changes to the template in the Source Editor. }MQNzaXY^
*/ ere h!
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package com.tot.count; =h5&:?X
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/** 7X
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* s8BfOl-
* @author k{\wjaf)
*/ DwSB(O#X
public class CountBean { DEJ0<pnQr
private String countType; p[oR4 HWr
int countId; %87D(h!.I4
/** Creates a new instance of CountData */ 1g_p`(
public CountBean() {} 5&A{IN
public void setCountType(String countTypes){ _G3L+St
this.countType=countTypes; h,-2+}
} 8xf]zM"Q
public void setCountId(int countIds){ YX*NjXL
this.countId=countIds; 2L!s'^m-
} Ao?y2 [sE
public String getCountType(){ QFekj@
return countType; XBx&&
} pHKcKqB*13
public int getCountId(){ <[.{aj]QV
return countId; P:D@5
} qZQB"Q.*
} *^[m?3"W
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CountCache.java gn82_
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/* 10tlD<eYb
* CountCache.java 7x>\/l(
* #/N;ScyUJT
* Created on 2007年1月1日, 下午5:01 t =LIkwD
* !s^[|2D_U
* To change this template, choose Tools | Options and locate the template under &<nj~BL
* the Source Creation and Management node. Right-click the template and choose -Cn x!g}
* Open. You can then make changes to the template in the Source Editor. pW4O[v`
*/ e^!>W %.7Z
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package com.tot.count; s!73To}>
import java.util.*; :O?+Ywn
/** UP<B>Y1a
* \7V[G6'{
* @author Sb QM!Q
*/ RnV#[bM{
public class CountCache { MZIZ"b
public static LinkedList list=new LinkedList(); ATRB9
/** Creates a new instance of CountCache */ wWYo\WH'
public CountCache() {} gh9Gc1tKt
public static void add(CountBean cb){
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if(cb!=null){
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list.add(cb); C>NLZMT
} d\O*Ol*/v
} s2=`haYu
} {!0f.nv
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CountControl.java f]sc[_n]
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/* '@6O3z_{
* CountThread.java R6m6bsZ`
* "!S7D>2y#
* Created on 2007年1月1日, 下午4:57 62.)fCQ^
* S7B\mv
* To change this template, choose Tools | Options and locate the template under tl6x@%\
* the Source Creation and Management node. Right-click the template and choose x@*RF:\}
* Open. You can then make changes to the template in the Source Editor. TI5<'
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*/ k,,Bf-?
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package com.tot.count; 0{^ 0>H0
import tot.db.DBUtils; e6`g[Ap
import java.sql.*; QZwZ4$jkiO
/** tkIpeL[d
* 99GK6}~TGm
* @author S1I# qb
*/ S^Mx=KJG
public class CountControl{ #fVk;]u`[3
private static long lastExecuteTime=0;//上次更新时间 Hb&C;lk
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 *-eDUT|O
/** Creates a new instance of CountThread */ $V870
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public CountControl() {} a&z$4!wQB
public synchronized void executeUpdate(){ .;J6)h
Connection conn=null; aN5"[&
PreparedStatement ps=null; t) uS7y
try{ /1BqC3]tL
conn = DBUtils.getConnection(); BAIR!
conn.setAutoCommit(false); )z\ 73|w
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 1j_
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for(int i=0;i<CountCache.list.size();i++){ 'ZFbyt Q2
CountBean cb=(CountBean)CountCache.list.getFirst(); <SKzCp\
CountCache.list.removeFirst(); STjk<DP(
ps.setInt(1, cb.getCountId()); yedEI[_4
ps.executeUpdate();⑴ *";O_ :C!
//ps.addBatch();⑵ k0bDEz.X
} Ud:;kI%Vj
//int [] counts = ps.executeBatch();⑶ +/>XOY|Ie
conn.commit(); P>nz8NRq
}catch(Exception e){ !sVW0JS h
e.printStackTrace(); 45 B
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} finally{ itmFZZh
try{ b"JX6efnN
if(ps!=null) { GHRr+
ps.clearParameters(); XXg~eu?
ps.close(); QTIC5cl,
ps=null; {
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} ZH)thd9^b
}catch(SQLException e){} Ba}<X;B }
DBUtils.closeConnection(conn); g/+|gHq^
} 1|WrJ-Uf
} ">FuCvQ
public long getLast(){ qFE(H1hy
return lastExecuteTime; ' OXL'_Xl
} sl_f+h0
public void run(){ OrY^ ?E
long now = System.currentTimeMillis(); %CV.xDE8
if ((now - lastExecuteTime) > executeSep) { ^wlo;.8Y
//System.out.print("lastExecuteTime:"+lastExecuteTime); cqG&n0zb
//System.out.print(" now:"+now+"\n"); /0YO`])"
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); LEd@""h
lastExecuteTime=now; _ SJFuv/
executeUpdate(); T@R2H&L
} 'FM_5`&
else{ #i 5@G*
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 888"X3.T
} 9j>LU<Z
} +>QD4z#
} RjxFlKs8
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 T9?8@p\}(
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类写好了,下面是在JSP中如下调用。 LMRq.wxbbB
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<% `u"
)*Q}
CountBean cb=new CountBean(); T4Io+b8$
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); $u cmE
CountCache.add(cb); 7v
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out.print(CountCache.list.size()+"<br>"); si1Szmx,
CountControl c=new CountControl(); PouWRGS_
c.run(); =sUrSVUeU
out.print(CountCache.list.size()+"<br>"); c7@[RG !
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