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: D,cD]tB2
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CountBean.java g$uiwqNA%
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/* ]Ozz"4Z
* CountData.java #`_W?-%^
* nk|(cyt)
* Created on 2007年1月1日, 下午4:44 Tv|'6P
* jA,y.(mR
* To change this template, choose Tools | Options and locate the template under e8`d<U
* the Source Creation and Management node. Right-click the template and choose ._0$#J S[
* Open. You can then make changes to the template in the Source Editor. 2!6hB sEr
*/ l -XfUjJ
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package com.tot.count; %g7j7$c
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/** GG#-x$jK
* t%mi#Gh(
* @author `lY-/Ty
*/ 0")_%
public class CountBean { ;rf{T[i
private String countType; i|h{<X7[
int countId; c^_+<C-F
/** Creates a new instance of CountData */ '{,JuX"n
public CountBean() {} )P7oL.)
public void setCountType(String countTypes){ mCnl@
this.countType=countTypes; +IXr4M&3
} 3SY1>}(Y
public void setCountId(int countIds){ W(qK?"s2
this.countId=countIds; r`ftflNh(
} D Z~036
public String getCountType(){ ]fY:+Ru
return countType; x<t?Yc9
} F4=X(P_6
public int getCountId(){ =>S[Dh
return countId; |+h x2?Nv
} ]#N8e?b,
} xRZ K&vkKE
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CountCache.java un\o&0}
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/* 1^AQLOiRE1
* CountCache.java y@}WxSK*0
* Urw =a$
* Created on 2007年1月1日, 下午5:01 C|
* ?z.
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* To change this template, choose Tools | Options and locate the template under FS7D
* the Source Creation and Management node. Right-click the template and choose VVF9X(^rQ
* Open. You can then make changes to the template in the Source Editor. oVl:g:K40
*/ f3;[ZS
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package com.tot.count; "Ml#,kU<T
import java.util.*; 9n5uO[D
/** v%#@.D!)
* 1< b~="
* @author 9QD+
*/ ga'G)d3oS
public class CountCache { !FK)iQy$0
public static LinkedList list=new LinkedList(); lNe5{'OrO
/** Creates a new instance of CountCache */ c*w0Jz>@.7
public CountCache() {} $U&p&pgH=W
public static void add(CountBean cb){ uv$utu><
*
if(cb!=null){ Vf(..8
list.add(cb); 4<EC50@.
} C,O9?t
} 0W
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} ]:#W$9,WL
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CountControl.java 75h]#k9\
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/* 6 {`J I
* CountThread.java ZP:+ '\&J
* ocS}4.a@
* Created on 2007年1月1日, 下午4:57 \^cXmyQ <%
* Vo%ikR #
* To change this template, choose Tools | Options and locate the template under .5~3D97X&
* the Source Creation and Management node. Right-click the template and choose 3#uc+$[
* Open. You can then make changes to the template in the Source Editor. .*?-j?U.
*/ V2yX;u
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package com.tot.count; u3cl7~- yW
import tot.db.DBUtils; F${}n1D
import java.sql.*; &`'@}o>2
/** -LFk7a
* z+c8G
* @author iII%!f?{[
*/ Ln4Dq[M
public class CountControl{ ^%1u3
private static long lastExecuteTime=0;//上次更新时间 ND3|wQ`M0
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 WxJaE;`Ige
/** Creates a new instance of CountThread */ $F/xv&t
public CountControl() {} MHCwjo"
public synchronized void executeUpdate(){ LCSJIt
Connection conn=null; O^~nf%
PreparedStatement ps=null; ]<;y_
try{ Tkj
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conn = DBUtils.getConnection(); *]Eyf")
conn.setAutoCommit(false); (F#2z\$;
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); e\ZV^h}TQ
for(int i=0;i<CountCache.list.size();i++){ Kciz^)'Z
CountBean cb=(CountBean)CountCache.list.getFirst(); tt&{f <*
CountCache.list.removeFirst(); nwi8>MG
ps.setInt(1, cb.getCountId()); 0\1g-kc!v
ps.executeUpdate();⑴ /W{^hVkvC
//ps.addBatch();⑵ ,W$&OD
} B?d+^sz]
//int [] counts = ps.executeBatch();⑶ OP``+z>
conn.commit(); ]0")iY_
}catch(Exception e){ FW4#/H
e.printStackTrace(); QwnqysNx4
} finally{ T|--ZRYn
try{ [KEw5-=i@
if(ps!=null) { S<I9`k G
ps.clearParameters(); wk2Ff*&
ps.close(); 0<Rq
ps=null; 1#XZVp;M
} Tog'3k9Uw
}catch(SQLException e){} "!#KQ''R
DBUtils.closeConnection(conn); ZQsVSz( 1
} k7nke^,|
} f5*hOzKG6
public long getLast(){
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return lastExecuteTime; 2t3)$\ylQp
} 7\i> >
public void run(){ F ^)(
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long now = System.currentTimeMillis(); `cFNO:
if ((now - lastExecuteTime) > executeSep) { Cv<
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//System.out.print("lastExecuteTime:"+lastExecuteTime); 6^ ,;^
//System.out.print(" now:"+now+"\n"); (I#3![q
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); >B$B|g~
lastExecuteTime=now; Ee{Y1W
executeUpdate(); T?*f}J
} u"U7aYGkY
else{ lG`%4}1
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 2GRv%:rZ
} fjqd16{Q
} gq.l=xS
} x.q "FXu
//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 eY`o=xN
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类写好了,下面是在JSP中如下调用。 )D7/[zb^
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<% TV?MB(mN
CountBean cb=new CountBean(); 8)YDUE%VH
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); $OaxetPH
CountCache.add(cb); $AdBX}{
out.print(CountCache.list.size()+"<br>"); T:*l+<?
CountControl c=new CountControl(); =F46v{la
c.run(); *~`BG5w
out.print(CountCache.list.size()+"<br>"); Upz?x{>x
%>