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: 2i1xSKRYrD
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CountBean.java `u PLyS.
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/* m]vV.pwv
* CountData.java fFWi
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* Hrph>v
* Created on 2007年1月1日, 下午4:44 #.$y
* R^P>yk8
* To change this template, choose Tools | Options and locate the template under "Aw)0a[j1
* the Source Creation and Management node. Right-click the template and choose 4RYH^9;>K
* Open. You can then make changes to the template in the Source Editor. @qj]`}Gx'
*/ |r36iUHZS
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package com.tot.count; >xq.bG
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/** P=\{
* Au}l^&,zN
* @author +oq<}CNr{
*/ x;\/Xj;
public class CountBean { F"O\uo:3
private String countType; gq/Za/!6
int countId; b78~{ht`
/** Creates a new instance of CountData */ (/,l0
public CountBean() {} xIC@$GP
public void setCountType(String countTypes){ i1-%#YYF(
this.countType=countTypes; /]MelW
} %Ta"H3ZW
public void setCountId(int countIds){ 0K26\1
this.countId=countIds; H:~u(N
} L$.3,./
public String getCountType(){ 0 yq
return countType; +}a(jO
} Jww#zEK
public int getCountId(){ X;Sb^c"j1
return countId; isQOt *
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} lG%697P
} OE9,D:tv
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CountCache.java ) ba~7A
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/* kLZVTVSJt
* CountCache.java l:uQ#Z)
* V
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* Created on 2007年1月1日, 下午5:01 ^87 9sI
* >X'-J{4R
* To change this template, choose Tools | Options and locate the template under WKlyOK=}
* the Source Creation and Management node. Right-click the template and choose kP ,8[r
* Open. You can then make changes to the template in the Source Editor. jy?*` q1]
*/ f17E2^(I(}
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package com.tot.count; r9'[7b1l
import java.util.*; j-W$)c3X
/** `Hlf.>b1
* dnU-v7k,{
* @author J:Qx5;b;
*/ hr 6j+p:
public class CountCache { ,f$P[c
public static LinkedList list=new LinkedList(); k:R\;l5
/** Creates a new instance of CountCache */ 1BZ##xV*:G
public CountCache() {} Ui`{U
public static void add(CountBean cb){ j&'6|s{
if(cb!=null){ 10*Tk 8
list.add(cb); vk48&8
} Kw"y#Ys]
} 3mo4;F,h9
} RO,TNS~
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CountControl.java a*U[;(
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/* Y$A2{RjRq
* CountThread.java to</
* o
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* Created on 2007年1月1日, 下午4:57 C9sU^]#F
* Vb\g49\o/
* To change this template, choose Tools | Options and locate the template under 2a
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* the Source Creation and Management node. Right-click the template and choose /}8Au$nA
* Open. You can then make changes to the template in the Source Editor. $S|+U}]C
*/ &um++
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package com.tot.count; [Tp?u8$p`
import tot.db.DBUtils; Zja3HGL
import java.sql.*; AG=PbY9
/** }3X/"2SW^
* 8TT#b?d
* @author Cd
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*/ YYYF a
public class CountControl{ `@],J
private static long lastExecuteTime=0;//上次更新时间 v#%rjml[
private static long executeSep=60000;//定义更新间隔时间,单位毫秒
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/** Creates a new instance of CountThread */ hQm=9gS
public CountControl() {} 0't)-Pj+,
public synchronized void executeUpdate(){ =CK% Zo
Connection conn=null; [1P_^.Htr
PreparedStatement ps=null; 'WP~-}(
try{ &AJkYh
conn = DBUtils.getConnection(); 1LRP
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conn.setAutoCommit(false); [,AFtg[
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); S*h^7?Bu
for(int i=0;i<CountCache.list.size();i++){ %"A8Af**I
CountBean cb=(CountBean)CountCache.list.getFirst(); >,]a>V
CountCache.list.removeFirst(); ~^Cx->l
ps.setInt(1, cb.getCountId()); r*vh3.Agl
ps.executeUpdate();⑴ Ia}qDGqPp!
//ps.addBatch();⑵ >B**fZ~L
} ZY`9
//int [] counts = ps.executeBatch();⑶ w+
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conn.commit(); 1Ys=KA-!_x
}catch(Exception e){ zP #:Tv'
e.printStackTrace(); B]G2P`sN
} finally{ ]A%3\)r
try{ Za|iU`e\
if(ps!=null) { #&Tm%CvB
ps.clearParameters(); |nx3x
ps.close(); ="& GU%$
ps=null; MLHCBRi
} AYfOETz
}catch(SQLException e){} 'sUOi7U
DBUtils.closeConnection(conn); IeYNTk&<
} e&VC}%m
} zl:by?
public long getLast(){ 6LCtWX
return lastExecuteTime; >:6iFPP
} yC\UT
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public void run(){ z.-yL,Rc`-
long now = System.currentTimeMillis(); HZRFE[ 9nb
if ((now - lastExecuteTime) > executeSep) { qr%N/7
//System.out.print("lastExecuteTime:"+lastExecuteTime); >
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//System.out.print(" now:"+now+"\n"); ?m]vk|>
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); Dnw^H.
lastExecuteTime=now; {. 9BG&
executeUpdate(); %eDSo9Y
} by
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else{ @iuX~QA[9
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); :k1?I'q%
} -#f.}H'
} )v_Wn[Y.H
} T"vf
//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 7wx=#
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类写好了,下面是在JSP中如下调用。 VU,G.eLW
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<% u>lt}0
CountBean cb=new CountBean(); 3 k/E$wOj
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); \[3~*eX6
CountCache.add(cb); h6D4CT
out.print(CountCache.list.size()+"<br>"); md+pS"8o;
CountControl c=new CountControl(); yor'"6)i
c.run(); <jV,VKL#
out.print(CountCache.list.size()+"<br>"); QNx]8r
%>