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: U,tWLX$@
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CountBean.java I7HP~v~
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/* ,H:{twc
* CountData.java 9Fh1rZD<
* |YK4V(5x
* Created on 2007年1月1日, 下午4:44 !--A"
* r=:o$e
* To change this template, choose Tools | Options and locate the template under "dFuQB
* the Source Creation and Management node. Right-click the template and choose ]7
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* Open. You can then make changes to the template in the Source Editor. hC2_Yr>N%
*/ RrRE$g
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package com.tot.count; :'K%&e?7s
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/** M|\C@,F]8
* |s{[<;
* @author =(]||1.
*/ %z5P%F'5
public class CountBean { Jsw%.<
private String countType; Bw*6X`'Q
int countId; /]hE?cmj
/** Creates a new instance of CountData */ 5 $:
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public CountBean() {} 5}he)2*uD
public void setCountType(String countTypes){ Fy-|E>@]D
this.countType=countTypes; )NCSO b
} Qhsk09K_=4
public void setCountId(int countIds){ 6^vHFJ$
this.countId=countIds; "6xTh0D
} 4kdQ h]
public String getCountType(){ sI#r3:?i
return countType; TptXH?
} ="AJ&BqHd
public int getCountId(){ pb=yQ}.
return countId; MP%pEUomev
} 07qL@![!
} Q0-}!5`E1$
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CountCache.java N83g=[
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/* "M4gl
* CountCache.java Ilv
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*
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* Created on 2007年1月1日, 下午5:01 "%fvA;
* D$PR<>=y
* To change this template, choose Tools | Options and locate the template under 8VLD yX2-
* the Source Creation and Management node. Right-click the template and choose .80L>0
* Open. You can then make changes to the template in the Source Editor. 7) e#b
*/ rulw6vTB(
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package com.tot.count; ey! {
import java.util.*; _)F0oC {
/** 4&/m>%r
* EE[JXoke
* @author [SA$d`B/
*/ \<4Hp_2?
public class CountCache { fk
public static LinkedList list=new LinkedList(); e+7x &-+
/** Creates a new instance of CountCache */ {Wh7>*p{3
public CountCache() {} 7(1UXtT
public static void add(CountBean cb){ Th\t6K~
if(cb!=null){ b.sRB1
list.add(cb); eK'ztqQ
} p@bcf5'
} i0e aBG]I
} 0F|DD8tHR
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CountControl.java &a];"2
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/* {5N!udLDr5
* CountThread.java SM@RELA'Lb
* L!V6Rfy
* Created on 2007年1月1日, 下午4:57 `1qM Sq
* PTFe>~vr*
* To change this template, choose Tools | Options and locate the template under M~#%
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* the Source Creation and Management node. Right-click the template and choose 7n*[r*$
* Open. You can then make changes to the template in the Source Editor. of>"qrdZ
*/ RmcQGQ
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package com.tot.count; -+w^"RBV
import tot.db.DBUtils; XVNJ3/
import java.sql.*; DV">9{"5']
/** a54qv^IS
* PDH00(#;+
* @author 6m!%X GZT
*/ i%a jL
public class CountControl{ !JE=QG"
private static long lastExecuteTime=0;//上次更新时间 qD?-&>dBWi
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 =Zc
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/** Creates a new instance of CountThread */ QwL'5ws{q
public CountControl() {} )i{B:w\ ^
public synchronized void executeUpdate(){ =(U&?1 R4
Connection conn=null; c<J/I_!
PreparedStatement ps=null; WG?;Z
try{ soi.`xE
conn = DBUtils.getConnection(); r7=r~3)
conn.setAutoCommit(false); g4fe(.?c,
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); Z_Z; g]|!
for(int i=0;i<CountCache.list.size();i++){ f}U@e0Lsb
CountBean cb=(CountBean)CountCache.list.getFirst(); % HK \
CountCache.list.removeFirst(); {Y#$
ps.setInt(1, cb.getCountId()); rS/}!|uAu
ps.executeUpdate();⑴ >:yU bo)
//ps.addBatch();⑵ 4:S?m(ah/
} t,m},c(B:
//int [] counts = ps.executeBatch();⑶ gNoQ[xFx32
conn.commit(); F"*.Qq
}catch(Exception e){ i9%cpPrg8
e.printStackTrace(); S0uEz;cE
} finally{ !p#+I=
try{ /"*eMe!=
if(ps!=null) { 5v@-.p
ps.clearParameters(); ywS2`(
ps.close(); qq1@v0
ps=null; Z}*{4V`R
} ;`P}\Q{
}catch(SQLException e){} $7bl,~Z
DBUtils.closeConnection(conn); TaN]{k
} M~+T
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} lImg+r T{
public long getLast(){ "2~%-;c
return lastExecuteTime; RN"O/b}qQ
} %W[#60
public void run(){ O3>m,v
long now = System.currentTimeMillis(); TUaW'
if ((now - lastExecuteTime) > executeSep) { *U69rbYI
//System.out.print("lastExecuteTime:"+lastExecuteTime); ejuw+@ _
//System.out.print(" now:"+now+"\n"); k_}aiHdG
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); Im* ~6[
lastExecuteTime=now; Zg#VZg1
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executeUpdate(); h72#AN
} PF4"J^V
else{ F:o<E 42
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); Qso"jYl<
} hn@T ]k
} D^~G(m;-
} yd-Kg zm8n
//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 1VD8y_tC
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类写好了,下面是在JSP中如下调用。 o :tz_5
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<% jg7WMH"`
CountBean cb=new CountBean(); }&{z-/;H
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); I3wv6xZ2
CountCache.add(cb); w6 x{<d
out.print(CountCache.list.size()+"<br>"); m)aNuQvy:Z
CountControl c=new CountControl(); fEB>3hI
c.run(); _Ka6! 9
out.print(CountCache.list.size()+"<br>"); D'!
v9}
%>