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: ?dTD\)%A
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CountBean.java 4H/OBR
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/* \V:^h[ad
* CountData.java cQ|NJ_F{1
* ]e3Ax(i)
* Created on 2007年1月1日, 下午4:44 NK+o1
* 3`HV(5U[
* To change this template, choose Tools | Options and locate the template under xw%0>K[
* the Source Creation and Management node. Right-click the template and choose <@}9Bid!o
* Open. You can then make changes to the template in the Source Editor. :UdF
*/ ,4rPg]r@
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package com.tot.count; PF2nLb2-
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/** =Qq+4F)MD
* Ac6=(B
* @author 5;?yCWc
*/ 'qi}|I
public class CountBean { G3]4A&h9v~
private String countType; H]s.=.Ki
int countId; a.'*G6~Qgw
/** Creates a new instance of CountData */ QJNFA}*>
public CountBean() {} qR.Q,(b|
public void setCountType(String countTypes){ e!`i3KYn"
this.countType=countTypes; (hsl~Jf
} ex|F|0k4}
public void setCountId(int countIds){ NI5``BwpO
this.countId=countIds; Vi}_{
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} v=k$A
public String getCountType(){ -di o5a
return countType; !wNO8;(
} ]9L
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public int getCountId(){ 4 :=]<sc,
return countId; {*KEP
} BY*Q_Et
} A
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CountCache.java x"(KBEK~
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/* /=h` L,
* CountCache.java ':W[ A
* OB7hlW
* Created on 2007年1月1日, 下午5:01 ddo#P%sH'
* 2tLJU Z1
* To change this template, choose Tools | Options and locate the template under 5r_|yu
* the Source Creation and Management node. Right-click the template and choose :EH=_"
* Open. You can then make changes to the template in the Source Editor. VX/#1StC
*/ r/sNrB1U"y
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package com.tot.count; q=G+Tocv
import java.util.*; F"<vaqT2
/** 2%>FR4a
* .-=vx r
* @author \1`O_DF~o
*/ b\ PgVBf9
public class CountCache { iUwzs&frd
public static LinkedList list=new LinkedList(); ]~%6JJN7
/** Creates a new instance of CountCache */ Wf<LR3
public CountCache() {} PX99uWx5]
public static void add(CountBean cb){ mt`.6Xz~
if(cb!=null){ XM}hUJJW
list.add(cb); s7EinI{^
} ,PZ ge
} V,9cl,z+
} {|\.i
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CountControl.java ?}7p"3j'z
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/* 7?t6UPf
* CountThread.java X@f}Q`{Ymj
* zT[!o
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* Created on 2007年1月1日, 下午4:57 I l.K"ll
* vI]N^j2%
* To change this template, choose Tools | Options and locate the template under tjnIN?YT
* the Source Creation and Management node. Right-click the template and choose rGkyGz8>
* Open. You can then make changes to the template in the Source Editor. X?$_Sd"G+5
*/ x`?3C"N:<
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package com.tot.count; >3_Gw4S*H
import tot.db.DBUtils; Ev P{p
import java.sql.*; j7c3(*Pl
/** VD :/PL
* l(q ,<[O
* @author 9/7u*>:
*/ @I*{f
public class CountControl{ ?s _5&j7
private static long lastExecuteTime=0;//上次更新时间 2m[<]$
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 :aQt;C6Z>
/** Creates a new instance of CountThread */ Z)\@i=m
public CountControl() {} 9,tej
public synchronized void executeUpdate(){ MS]r:X6
Connection conn=null; r9lR|\Ax2U
PreparedStatement ps=null; _y>~
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try{ HKr
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conn = DBUtils.getConnection(); ;\l,5EG
conn.setAutoCommit(false); qv*^fiT
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); +]50D xflA
for(int i=0;i<CountCache.list.size();i++){ `p7=t)5k
CountBean cb=(CountBean)CountCache.list.getFirst(); )0R'(#
CountCache.list.removeFirst(); rt|7h>RQ
ps.setInt(1, cb.getCountId()); <o= 8FO
ps.executeUpdate();⑴ z~Q>V]a>;
//ps.addBatch();⑵ +U.I( 83F
} 9I/N4sou
//int [] counts = ps.executeBatch();⑶ MxGW(p
conn.commit(); p^u:&Quac
}catch(Exception e){ @<Yy{~L|
e.printStackTrace(); l$'wD hN*
} finally{ }{<
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try{ e,5C8Q`Z
if(ps!=null) { C/&-l{7
ps.clearParameters(); d'I"jZ
ps.close(); TW>WHCAm
ps=null; s!e3|pGS
} }#E[vRf
}catch(SQLException e){} 8Bg;Kh6B
DBUtils.closeConnection(conn); 4NIRmDEd
} 5P$4 =z91
} Zsh9>]ML
public long getLast(){ gl_^V&c
return lastExecuteTime; v]c6R-U
} S/I /-Bp~
public void run(){ s|B3~Q]
long now = System.currentTimeMillis(); :U(A;U1,
if ((now - lastExecuteTime) > executeSep) { a -moI+y
//System.out.print("lastExecuteTime:"+lastExecuteTime); f>Jr|#k
//System.out.print(" now:"+now+"\n"); ~F?u)~QZ#
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); BI}Cg{^km
lastExecuteTime=now; -FlzEZ
executeUpdate(); {$Gd2gO
} 7(
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else{ Ji 0
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//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 5lT*hF
} PIpi1v*qz
} $"&{aa
} m7>JJX3=<
//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 ~**.|%Kc
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类写好了,下面是在JSP中如下调用。 t3Y:}%M
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<% }XM(:|8J,
CountBean cb=new CountBean(); yqiq,=OvP
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); nL.<[]r
CountCache.add(cb); *``JamnSO
out.print(CountCache.list.size()+"<br>"); !GEJIefx_
CountControl c=new CountControl(); 0tB0@Wj
c.run(); *~j@*{u
out.print(CountCache.list.size()+"<br>"); `P;s8~
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