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: _nIqy&<
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CountBean.java F~d7;x=g
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/* 5LhJ8$W
* CountData.java x":Bw;~
* J:TI>*tn
* Created on 2007年1月1日, 下午4:44 Zc' >}X[G
* O>"r. sR
* To change this template, choose Tools | Options and locate the template under u;'<- _
* the Source Creation and Management node. Right-click the template and choose *nUpO]
* Open. You can then make changes to the template in the Source Editor. c|;|%"Mk
*/ _QOOx+%*5
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package com.tot.count; <>5:u
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/** 1l`s1C
* #K,qF*
* @author pb2{J#
*/ @D=2Er\
public class CountBean { Gad2EEZ%0
private String countType; ^hYR5SX
int countId; YK=#$,6
/** Creates a new instance of CountData */ ^1FZ`2u;
public CountBean() {} ;P0Y6v3
public void setCountType(String countTypes){ ?/|@ #&
this.countType=countTypes; )(|0KarF
} /NN[gz
public void setCountId(int countIds){ uI:3$
this.countId=countIds; |@Idf`N$
} 2Ws/0c
public String getCountType(){ dc@wf;o
return countType; Cak/#1
} C&s }m0R
public int getCountId(){ /x8C70W^
return countId; :]z-Rz
} M]/wei"X
} .V )2Tz
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CountCache.java OTtanJ?
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/* @2Y]p.$q
* CountCache.java ZX5A%`<M
* Z :i"|;
* Created on 2007年1月1日, 下午5:01 .Zo9^0`C
* 8IIdNd
* To change this template, choose Tools | Options and locate the template under 4U y>#IL
* the Source Creation and Management node. Right-click the template and choose $j4?'-i=e
* Open. You can then make changes to the template in the Source Editor. 5SWX v+
*/ CO)b'V,
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package com.tot.count; F~@1n,[
import java.util.*; *~oDP@[S
/** -Fw4;&>
* fz?Wr: I
* @author *y\tns U
*/ ;KZ2L~
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public class CountCache { kc(b;EA
public static LinkedList list=new LinkedList(); -mYI[AG)
/** Creates a new instance of CountCache */ {arjW3~M:
public CountCache() {} o-i.'L)X
public static void add(CountBean cb){ g:e8i~
if(cb!=null){ K|J#/
list.add(cb); Y(!)G!CMc
} UmI@":|-
} YU \t+/b
} +7vh_ _
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CountControl.java = {DB
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/* 89e.\EH
* CountThread.java ;\&bvGj8V
* f'yd{ihFp
* Created on 2007年1月1日, 下午4:57 l aL4ez
* n\)f.}YD8d
* To change this template, choose Tools | Options and locate the template under 1bAp{u&
* the Source Creation and Management node. Right-click the template and choose Mn{Rg>X
* Open. You can then make changes to the template in the Source Editor. j9fL0$+FI
*/ zs^\zCb8
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package com.tot.count; ez9M]! 8Lt
import tot.db.DBUtils; fq!6#Usf;i
import java.sql.*; }sNZQ89V*v
/** eDZ3SIZ
* RKZk/ly
* @author gR6T]v
*/ c+M@{EbuN
public class CountControl{ J0) WRn"h
private static long lastExecuteTime=0;//上次更新时间 z+B
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 W p*
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/** Creates a new instance of CountThread */ ^?VT y5yp
public CountControl() {} 0`Qs=R`OM
public synchronized void executeUpdate(){ +fR`@HI
Connection conn=null; J3JRWy@?P
PreparedStatement ps=null; iQj{J1V
try{ E|}Nj}(*
conn = DBUtils.getConnection(); rG%_O$_dO
conn.setAutoCommit(false); SmEd'YD!J
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?");
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for(int i=0;i<CountCache.list.size();i++){ G8c}re
CountBean cb=(CountBean)CountCache.list.getFirst(); }pZnWK+
CountCache.list.removeFirst(); (I 0t*Se
ps.setInt(1, cb.getCountId()); -Z&{$J
ps.executeUpdate();⑴ +|w~j#j9`
//ps.addBatch();⑵ aRKG)0=
} 1{glRY'
//int [] counts = ps.executeBatch();⑶ e ^&8x
conn.commit(); lMf5F8
}catch(Exception e){ ,
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e.printStackTrace(); s-DL=MD
} finally{ vK>^#b3
try{ q&S.C9W
if(ps!=null) { Mj;'vm7#'
ps.clearParameters(); _C#()#
ps.close(); H~K2`Cr)4
ps=null; MX_a]$\:n
} Nfvg[c
}catch(SQLException e){} R20GjWy=
DBUtils.closeConnection(conn); KD*4n'm!>
} bg. KkJMrR
} {v'Fg
public long getLast(){ ! \Kh\
return lastExecuteTime; 71ybZ 0
} Hx0,kOh)
public void run(){ [uV/ Ra*g
long now = System.currentTimeMillis(); No|{rYYKK
if ((now - lastExecuteTime) > executeSep) { 3CRBu:)m
//System.out.print("lastExecuteTime:"+lastExecuteTime);
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//System.out.print(" now:"+now+"\n"); 6$.Xj\zl
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); };sm8P{M
lastExecuteTime=now; ~"B[6^sW
executeUpdate(); s*WfRY*=V
} /T(~T
else{ 3c6)
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 6>A8#VT
} e-meUf9
} ];]EK6dzG
} (3*Hl
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 FaM~ 56Pa
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类写好了,下面是在JSP中如下调用。 ]bSt[
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<% 7FFYSv,[:
CountBean cb=new CountBean(); k3kqgR*
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); aE$p;I
CountCache.add(cb); a5&j=3)|
out.print(CountCache.list.size()+"<br>"); 5ZxBmQ
CountControl c=new CountControl(); )gF9D1eA
c.run(); %QbrVl+
out.print(CountCache.list.size()+"<br>"); u^p[zepW\
%>