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: (Iq\+@xE=
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CountBean.java SQ1&n;M}f
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/* [c W
* CountData.java vCmh3TQ
* ih;TQ!c+b
* Created on 2007年1月1日, 下午4:44 x)U;
* *xjIl<`pK
* To change this template, choose Tools | Options and locate the template under ~Igo
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* the Source Creation and Management node. Right-click the template and choose RI*%\~6t?
* Open. You can then make changes to the template in the Source Editor. L"-&B$B:
*/ C4cg,>P7
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package com.tot.count; *|3z($*U]
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/** -'VT
* Lul?@>T
* @author VN".NEL
*/ Ce)Wvuh
public class CountBean { , XR8qi~
private String countType; `dNb%f>
int countId; 7>mYD3
/** Creates a new instance of CountData */ vSL{WT]m
public CountBean() {} h/VYH(Tj
public void setCountType(String countTypes){ ]s SoIT
this.countType=countTypes; 2M1mdkP3
} ZT8j9zs
public void setCountId(int countIds){ Oxvw`a#
this.countId=countIds; 68>zO%
} ?d0Dfqh_
public String getCountType(){ lKwcT!Q4
return countType; >k jJq]A2
} W P&zF$
public int getCountId(){ "|%fAE
return countId; P3|<K-dFAK
} +]zP $5_e
} CKur$$B
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CountCache.java yLX#:
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/* vJ'
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* CountCache.java #lC{R^SL
* x M[#Ah)
* Created on 2007年1月1日, 下午5:01 igL^k`&5^"
* Lgfr"{C
* To change this template, choose Tools | Options and locate the template under srkOad
* the Source Creation and Management node. Right-click the template and choose gA|j\T{c
* Open. You can then make changes to the template in the Source Editor. u^uG_^^,/
*/ TDGzXJf[
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package com.tot.count; ;v'Y'!-J
import java.util.*; OY#_0p)i
/** F&~vD
* pp`U]Q5"gX
* @author *~L]n4-
*/ t*#&y:RG
public class CountCache { X9j+$X\j
public static LinkedList list=new LinkedList(); =R"tnjR
/** Creates a new instance of CountCache */ $gTPW,~s[
public CountCache() {} 5S?yj
public static void add(CountBean cb){ 463dLEd
if(cb!=null){ }{y$$X<:
list.add(cb); BSf"'0I&
} [ub\DLl
} \nWpV7TSN
} (jG$M= q-
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CountControl.java :<gk~3\
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/* `ahXn
* CountThread.java {;/o4[jlg
* t_dg$KB
* Created on 2007年1月1日, 下午4:57 9="sx 8?
* 9R[','x
* To change this template, choose Tools | Options and locate the template under $C/Gn~k 5
* the Source Creation and Management node. Right-click the template and choose 3\G=J
* Open. You can then make changes to the template in the Source Editor. %R>S"
*/ K=)R!e8
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package com.tot.count; pAuwSn#i
import tot.db.DBUtils; 5XHkRcESZ
import java.sql.*; 1%`:8
/** '7R'fhiO/3
* <k6xScy$}
* @author POXn6R!mM1
*/ MvmP["%J4_
public class CountControl{ "-?Y UY`
private static long lastExecuteTime=0;//上次更新时间 z-G (!]:
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 lz 6 Aj
/** Creates a new instance of CountThread */ r|@?v ,
public CountControl() {} WRyLpTr-
public synchronized void executeUpdate(){ J.l%HU
Connection conn=null; V1`|j
PreparedStatement ps=null; Qknc.Z}
try{ zOdKB2_J7
conn = DBUtils.getConnection(); sD+G+
conn.setAutoCommit(false); du,-]fF
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ^nF$<#a
for(int i=0;i<CountCache.list.size();i++){ jYz3(mM'J
CountBean cb=(CountBean)CountCache.list.getFirst(); dDbC0} x/
CountCache.list.removeFirst(); eb\`)MI/
ps.setInt(1, cb.getCountId()); <GRf%zJ
ps.executeUpdate();⑴ 9A(K_d-!H
//ps.addBatch();⑵ +GU16+w~E
} UD`Z;F
//int [] counts = ps.executeBatch();⑶ |/;5|
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conn.commit(); f :5/y^M&
}catch(Exception e){ ,?6m"ov4(
e.printStackTrace(); u_8 22Z
} finally{ z]AS@}wWqg
try{ @\8gzvkt
if(ps!=null) { A#:
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ps.clearParameters(); mU$7_7V~
ps.close(); vKC&Qi ;
ps=null; %Qz`SO8x?
} vq7%SEkES
}catch(SQLException e){} 7F:;3c
DBUtils.closeConnection(conn); 3+5\xRq
} i%8&g2
} qL.Y_,[[
public long getLast(){ U(4_X[qD
return lastExecuteTime; E(_I3mftm
} nk
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public void run(){ re J?38(
long now = System.currentTimeMillis(); m0\}Cc
if ((now - lastExecuteTime) > executeSep) { vPNZFi-(
//System.out.print("lastExecuteTime:"+lastExecuteTime); =Gz>ZWF
//System.out.print(" now:"+now+"\n"); ,{*fOpn
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); @I6 A9do
lastExecuteTime=now; KB*=a
executeUpdate(); 7=A9E]:
} {Y%=/ba W
else{ F|`B2Gr
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); [#'_@zZz
} Qm x~_
} >%dAqYi $
} ibs"Iv34
//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 no6]{qn=6
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类写好了,下面是在JSP中如下调用。 NOp=/
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<% Q8cPKDB
CountBean cb=new CountBean(); , %O3^7i
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); `f+g A
CountCache.add(cb); +/86w59
out.print(CountCache.list.size()+"<br>"); 1|w:xG^
CountControl c=new CountControl(); ?Hxgx
c.run(); z2V8NUn
out.print(CountCache.list.size()+"<br>"); rOr1H!
%>