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: !4@G3Ae22
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CountBean.java Huw\&E
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/* 0x2!<z
* CountData.java A?5E2T1L%.
* 4S0>-?{
* Created on 2007年1月1日, 下午4:44 F7m?xy
* ge3sU5iZ
* To change this template, choose Tools | Options and locate the template under >r/rc`Q
* the Source Creation and Management node. Right-click the template and choose XhzGLYb~I`
* Open. You can then make changes to the template in the Source Editor. Rn%N&1
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*/ Ko>&)%))$X
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package com.tot.count; 4o:hyh
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/** =tTqN+4
* 2],_^XBvB
* @author @*N)i?>
*/ ]Hj<IvG
public class CountBean { 9ch#}/7B
private String countType; Z[!d*O%R_
int countId; Ey{%XR+*;
/** Creates a new instance of CountData */ 1iT\df
public CountBean() {} k#TYKft
public void setCountType(String countTypes){ %WG9 dYdS
this.countType=countTypes; 31+;]W=
} {Ee>n^1
public void setCountId(int countIds){ C8N{l:1f]
this.countId=countIds; ek aFN\
} _zxLwU1(x
public String getCountType(){ _?7#MWe&
return countType; .N4
} 5pNY)>]t=
public int getCountId(){ 6< J
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return countId; =!Vf
} h 6G/O`:
} HJ?+A-n/
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CountCache.java fqz28aHh
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/* *x~xWg9^
* CountCache.java qVjWV$j
* |6:=}dE#[
* Created on 2007年1月1日, 下午5:01 5 v^yQ<70
* z><5R|Gf
* To change this template, choose Tools | Options and locate the template under {eJt,[Y *
* the Source Creation and Management node. Right-click the template and choose bo"%0?3n
* Open. You can then make changes to the template in the Source Editor. ,iNv'
*/ Yw3oJf&
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package com.tot.count;
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import java.util.*; mN`YuR~
/** 5 /",<1
* ] U@o0
* @author 2 gq$C"
*/ }F6<w{|
public class CountCache { VO3pm6r5
public static LinkedList list=new LinkedList(); QZAB=rR
/** Creates a new instance of CountCache */ 0oA{Jix
public CountCache() {} JG`Q;K
public static void add(CountBean cb){ yZ]:y-1
if(cb!=null){ 9L0GLmLk1u
list.add(cb); !9*c8bL D
} ,y`CRlr:
} ,ea^,H6
} S 6,4PP
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CountControl.java # M, 7
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/* iO/XhSD
* CountThread.java !2\ r LN
* E"iUq
* Created on 2007年1月1日, 下午4:57 ha@L94Lq
* p=GWq(S6
* To change this template, choose Tools | Options and locate the template under v!3A9!.
* the Source Creation and Management node. Right-click the template and choose DDT_kK;
* Open. You can then make changes to the template in the Source Editor. zIC;7 5#
*/ qL6c`(0
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package com.tot.count; rVvR!"//yH
import tot.db.DBUtils; K`&oC8p
import java.sql.*; 8*SDiZ
/** gXT9 r' k
* I3 =#@2
* @author %V&n*3
*/ !?f5>Bl
public class CountControl{ CZnK8&VDY
private static long lastExecuteTime=0;//上次更新时间 Tm^89I]L
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 #1c]PX
/** Creates a new instance of CountThread */ wS+V]`b
public CountControl() {} yNW\?Z$@q
public synchronized void executeUpdate(){ I&?Qq k
Connection conn=null; &*G<a3Q
PreparedStatement ps=null; m42T9wSsx
try{ k$5 s{q
conn = DBUtils.getConnection(); 2Y}?P+:%>
conn.setAutoCommit(false); 65z"
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); a8u9aEB
for(int i=0;i<CountCache.list.size();i++){ dca;'$
CountBean cb=(CountBean)CountCache.list.getFirst(); YzosZ! L!<
CountCache.list.removeFirst(); nKR{ug>I)
ps.setInt(1, cb.getCountId()); n%h^o
ps.executeUpdate();⑴ ')a(.f
//ps.addBatch();⑵ 5tJ,7Y'
} kK8itO
//int [] counts = ps.executeBatch();⑶ }nt*
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conn.commit(); |r
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}catch(Exception e){ z"D.Bm~ ]
e.printStackTrace(); G;>
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} finally{ Nu8Sr]p
try{ ly% F."v
if(ps!=null) { aKU*j9A?;Z
ps.clearParameters(); "~UUx"Y
ps.close(); 0CSv10Tg
ps=null; ( mxT2"fC
}
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}catch(SQLException e){} bo.(zAz
DBUtils.closeConnection(conn); Cs2;z:O]
} $/Aj1j`"9+
} dEBcfya
public long getLast(){ A+@&"
return lastExecuteTime; :Xc@3gF
} NvM*h%ChM
public void run(){ (&$VxuJ+6y
long now = System.currentTimeMillis(); B|o2K}%f
if ((now - lastExecuteTime) > executeSep) { MX>[^}n
//System.out.print("lastExecuteTime:"+lastExecuteTime); #plY\0E@
//System.out.print(" now:"+now+"\n"); fs/*V~@
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ]v+31vdf:O
lastExecuteTime=now; U%0Ty|$Y
executeUpdate(); W0I#\b18
} Y8flrM2CwG
else{ o\vBOp?hj
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); \.M*lqI
} g^zs,4pPU<
} 8,dBl!G=
} C]Q8:6b
//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 r(gXoq_w
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类写好了,下面是在JSP中如下调用。 B=|cS;bM$3
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<% >:lnt /N3
CountBean cb=new CountBean(); +}jJ&Z9)
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 6;b~Ht
CountCache.add(cb); qWw\_S
out.print(CountCache.list.size()+"<br>"); (p%>j0<
CountControl c=new CountControl(); cu+FM
c.run(); O$4yAaD
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out.print(CountCache.list.size()+"<br>"); rj!0GI
%>