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: V,uhBMT#
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CountBean.java rrSA.J{
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/* tE{7S/?h
* CountData.java l!ye\
* aAko-,URC
* Created on 2007年1月1日, 下午4:44 !qH=l-7A
* MjU>qx::
* To change this template, choose Tools | Options and locate the template under {kJ[) 7
* the Source Creation and Management node. Right-click the template and choose
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* Open. You can then make changes to the template in the Source Editor. $Mx.8FC +
*/ kmW!0hm;e
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package com.tot.count; nm'm*sU\
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/** JoZC+G
* "`:#sF9S
* @author /]xd[^
*/ j.CC.[$g
public class CountBean { YA^9, q6u?
private String countType; CSU> nIE0
int countId; $zCUQthL@
/** Creates a new instance of CountData */ $)@zlnU
public CountBean() {} HIhoYSwB
public void setCountType(String countTypes){ >[xQUf,p
this.countType=countTypes; I{cn ,,8
} S0=BfkHi.
public void setCountId(int countIds){ *OF7{^~&
this.countId=countIds; 4r(rWlM
} ]Ly)%a32
public String getCountType(){ 'd?8OV
return countType; PfrW,R~r
} JsPuxu_
public int getCountId(){ kd\G>
return countId; .yWdlq##
} Fr%KO)s2
} udc9$uO
+[2lS54"W4
CountCache.java 00pHnNoxW
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/* !#iP)"O
* CountCache.java hGus!p"lw
* db%`-UST
* Created on 2007年1月1日, 下午5:01 P6=|C;[
* >Ft jrEB
* To change this template, choose Tools | Options and locate the template under `ZefSmb
* the Source Creation and Management node. Right-click the template and choose FpRK^MEkG
* Open. You can then make changes to the template in the Source Editor. #3CA
*/ h V8A<VT
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package com.tot.count; SyYa_=En
import java.util.*; _ve7Is`/
/** -`?V8OwY]
* d'-^VxO0
* @author Dkdm~~Rr
*/ E0oJ|My
public class CountCache { xUrfH$$!`
public static LinkedList list=new LinkedList(); ;8b f5
/** Creates a new instance of CountCache */ n6uobo-
public CountCache() {} f:utw T
public static void add(CountBean cb){ E_y h9lk
if(cb!=null){ &FanD
list.add(cb); ?y04g u6p
} :!A@B.E
} z(%Zji@!N
} W4YC5ZH{l
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CountControl.java >$"bwr}'4B
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/* i'EXylb
* CountThread.java 5g&'n
* a,tP.Xsl
* Created on 2007年1月1日, 下午4:57 d~_OWCg`
* [}AcCXg`L
* To change this template, choose Tools | Options and locate the template under 7PvuKAv?k
* the Source Creation and Management node. Right-click the template and choose [wOO)FjT
* Open. You can then make changes to the template in the Source Editor. 54)}^ftY^
*/ g{ a0,B/j
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package com.tot.count; $i`YtV
import tot.db.DBUtils; kdo)y(fn@
import java.sql.*; FVpe*]
/** QDDSJ>l5_T
* kB:R-St
* @author eeX>SL5'i
*/ 0!zWXKX
public class CountControl{ 2Vi[qS^
private static long lastExecuteTime=0;//上次更新时间 Z3/ zUtgs
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 HYY|)Wo
/** Creates a new instance of CountThread */ [p(C:rH
public CountControl() {} [lJ[kr*7
public synchronized void executeUpdate(){ z DK+8
Connection conn=null; TUUBC%
PreparedStatement ps=null; 3whyIXs
try{ FPMW"~v
conn = DBUtils.getConnection(); fGfv{4R
conn.setAutoCommit(false); ~>EVI=?
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); >]`x~cE.5
for(int i=0;i<CountCache.list.size();i++){ OL=b hZ
CountBean cb=(CountBean)CountCache.list.getFirst(); 9!OpW:bR|
CountCache.list.removeFirst(); KG?]MVXA
ps.setInt(1, cb.getCountId()); T<?;:MO88
ps.executeUpdate();⑴ D;E&;vP6%
//ps.addBatch();⑵ xSf3Ir(,
} .KD07
//int [] counts = ps.executeBatch();⑶ j?,$*Fi
conn.commit(); 0j yokER
}catch(Exception e){ 2,fB$5+
e.printStackTrace(); R3<+z
} finally{ $200?[
try{ Yl f4q/-
if(ps!=null) { S&0x:VW
ps.clearParameters(); =os j}(
ps.close(); ^m7PXY
ps=null; ,s)H%
} (*1A0+S90
}catch(SQLException e){} cZ(XY}
DBUtils.closeConnection(conn); "&ks83
} g=%&p?1@E
} yqU++;6
public long getLast(){ I@B7uFj
return lastExecuteTime; bM'AD[
} Ob6vg^#
public void run(){ 3m^BYr*y^
long now = System.currentTimeMillis(); jL8zH
if ((now - lastExecuteTime) > executeSep) { izxCbbg
//System.out.print("lastExecuteTime:"+lastExecuteTime); )<|T Ep4r-
//System.out.print(" now:"+now+"\n"); Y `{U45
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); q}!4b'z^
lastExecuteTime=now; c' 6H@m#=
executeUpdate(); 8+u8piG
} gM*s/,;O"
else{ Vh<`MS0X
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); Dz{e@+>M
} a !IH-XJ2
} ZUu^==a
} W< n`[
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 9NT;^K^I
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类写好了,下面是在JSP中如下调用。 \x!>5Z
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<% @FTi*$Ix
CountBean cb=new CountBean(); cNVdGY%&
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); "Wm~\)t(
CountCache.add(cb); DHAWUS6
out.print(CountCache.list.size()+"<br>"); ~JXHBX
CountControl c=new CountControl(); %Z7!9+<
c.run(); g{%';
out.print(CountCache.list.size()+"<br>"); )~/U+,
%>