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: |"Rl_+d7D
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CountBean.java g@<E0
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/* oBm^RHTZ
* CountData.java R>ak 3Y
* !2R<T/9~
* Created on 2007年1月1日, 下午4:44 NiCH$+c\
* aa'u5<<W
* To change this template, choose Tools | Options and locate the template under $p)7k
* the Source Creation and Management node. Right-click the template and choose huu v`$~y
* Open. You can then make changes to the template in the Source Editor. ;m;a"j5
*/ Oh\+cvbG
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package com.tot.count; Kc>C$}/}$
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/** mv,<#<-W
* "K"]/3`k-
* @author AV%?8-
*/ %4%$NdU"
public class CountBean { [^cflmV
private String countType; 4rmSo^vK
int countId; Gl1Qbd0
/** Creates a new instance of CountData */ ^+ hJ& 9W
public CountBean() {} ]$StbBP
public void setCountType(String countTypes){ T JB)]d<
this.countType=countTypes; <H Le,
} O%g%*9
public void setCountId(int countIds){ X/
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this.countId=countIds; $ON4nx
} abHW[VP9
public String getCountType(){ VPKoBJ&
return countType; Nvlfi8.
} 5i+0GN3nd
public int getCountId(){ \uumNpB*n
return countId; f?ImQYqP
} nZfU:N
} =
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CountCache.java H9x,C/r,
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/* w/L^w50pt
* CountCache.java |r]f2Mrm
* D*>EWlZ
* Created on 2007年1月1日, 下午5:01 O:=%{/6&D
* MpV3.
* To change this template, choose Tools | Options and locate the template under %7X<:f|N8x
* the Source Creation and Management node. Right-click the template and choose ?y] q\>
* Open. You can then make changes to the template in the Source Editor. 62R94
*/ {M7`z,,[
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package com.tot.count; m#D+Yh/y{n
import java.util.*; -`iXAyr)m
/** \k#|[d5W
* an4^(SY
* @author ,_JhvPWR,)
*/ uN:|4/;{&
public class CountCache { },"T,t#
public static LinkedList list=new LinkedList(); ndSM*Fq
/** Creates a new instance of CountCache */ JJ50(h)U
public CountCache() {} ]%{.zl!
public static void add(CountBean cb){ GwOn&EpY!
if(cb!=null){ BEQ$p)
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list.add(cb); X>[x7t:
} *Cdw"n
} 9 >t
} 9@Iz:!oqb
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CountControl.java NF}QQwG3
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/* 73-*|@6
* CountThread.java "l-L-sc,
* (1
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* Created on 2007年1月1日, 下午4:57 YF+hN\
* ~*3obZ2>2
* To change this template, choose Tools | Options and locate the template under *h<=
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* the Source Creation and Management node. Right-click the template and choose J3]!<v=
* Open. You can then make changes to the template in the Source Editor. V~Zi #o
*/ ]x8_f6;D
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package com.tot.count; L[]*vj
import tot.db.DBUtils; fn%Gu s~
import java.sql.*; u|!On
/** 0ssKZ9Lc
* &C~R*
* @author N1lhlw6
*/ 9`"o,wGX3
public class CountControl{ I)xB I~x
private static long lastExecuteTime=0;//上次更新时间 Qy)+YhE
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 Xq3n7d.
/** Creates a new instance of CountThread */ LvWl*:z
public CountControl() {} i6"/GSA
public synchronized void executeUpdate(){ ? m$uqi
Connection conn=null; |-WoR u
PreparedStatement ps=null; dDuT,zP
try{ 3)F9:Tzw1
conn = DBUtils.getConnection(); Cm~h\+"
conn.setAutoCommit(false); \9U4V>p
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); y8Q96zi
for(int i=0;i<CountCache.list.size();i++){ =h?Q.vad
CountBean cb=(CountBean)CountCache.list.getFirst(); .Z,3:3,]
CountCache.list.removeFirst(); 5yvaY
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ps.setInt(1, cb.getCountId()); FmfPi
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ps.executeUpdate();⑴ $jt UQ1
//ps.addBatch();⑵ ,BK6a'1J
} ;l^4/BR
//int [] counts = ps.executeBatch();⑶ {U$qxC]M
conn.commit(); v&6=(k{E@R
}catch(Exception e){ -mSiZ
e.printStackTrace(); _%HpB=
} finally{ 81\$X
try{ J{GtH[
if(ps!=null) { K3eYeXV
ps.clearParameters(); w#?@ulr]d
ps.close(); Hpo/CY/
ps=null; TY|5O!
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} fI{ZElPp
}catch(SQLException e){} b.qp&2 A
DBUtils.closeConnection(conn); nI1DLVt
} _3q%
} 4$~]t:n
public long getLast(){ RwH<JaL:
return lastExecuteTime; |{#=#3X
} T5mdC
public void run(){ Hx}K
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long now = System.currentTimeMillis(); -qki^!Y?
if ((now - lastExecuteTime) > executeSep) { |E\0Rv{H3
//System.out.print("lastExecuteTime:"+lastExecuteTime); }3t bqFiH
//System.out.print(" now:"+now+"\n"); CgLS2
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); M`W%nvEDE
lastExecuteTime=now; (S:+#v
executeUpdate(); traJub
} 5lp
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else{ L*ZC`
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//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); {x{/{{wzv
} Yp8~wdm
} 7g-#v'.N
} btq`[gAF\
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 KFCL|9P
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类写好了,下面是在JSP中如下调用。 yOn +Y
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<% F{1;~Yg%
CountBean cb=new CountBean(); }$K2h*
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); %-~W|Y
CountCache.add(cb); +39Vxe:Oy
out.print(CountCache.list.size()+"<br>"); ^!]Hm&.a
CountControl c=new CountControl(); +ahr-v^R<
c.run(); Oeo:V"
out.print(CountCache.list.size()+"<br>"); H].G%,2'
%>