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: p9/bzT34.
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CountBean.java <Cu'!h_nL
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/* i B%XBR
* CountData.java dj3|f{kg{
* Mx^y>\X)v
* Created on 2007年1月1日, 下午4:44 kXigX-
* b+W)2rFO
* To change this template, choose Tools | Options and locate the template under XlRw Z/Wc
* the Source Creation and Management node. Right-click the template and choose W7%p^;ZQ$
* Open. You can then make changes to the template in the Source Editor. zs4>/9O
*/ T48BRVX-F
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package com.tot.count; ]AFj&CteZ/
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/** -_s%8l^
* DD2adu^
* @author IS-}:~Pi
*/ \'[3^/('
public class CountBean { s;s0}Td_1
private String countType; s jSi;S4
int countId; ]t*33
/** Creates a new instance of CountData */ :b"=KQ
public CountBean() {} \$'R+k-57;
public void setCountType(String countTypes){ :eSc;
this.countType=countTypes; OSU{8.
} V:(y*tFA
public void setCountId(int countIds){ jh>N_cp
this.countId=countIds; 37#cx)p^f
} F@g17 aa
public String getCountType(){ eUYZxe :6
return countType; P=2wkzeJj
} P2O\!'aEh
public int getCountId(){ uG4$2
return countId; HHZ`%
} -4 8`#"xy
} {&E?<D2_&
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CountCache.java "";=DH
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/* M
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* CountCache.java PVhik@Yoh
* @]*[c})/
* Created on 2007年1月1日, 下午5:01 `4_c0q)N4
* </,.K`''W
* To change this template, choose Tools | Options and locate the template under cxgE\4_u"
* the Source Creation and Management node. Right-click the template and choose $Tfm/ =e
* Open. You can then make changes to the template in the Source Editor. >Dxe>Q'df
*/ 87pnSj/X"
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package com.tot.count; z23#G>I&
import java.util.*; OH>r[,z0
/**
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* nkTYWw
* @author (9E( Q*J5x
*/ / HL_$g<
public class CountCache { nMkOUW:T!
public static LinkedList list=new LinkedList(); 7vw;Egd@@-
/** Creates a new instance of CountCache */ ~)_K"h.DY
public CountCache() {} 2.ew^D#
public static void add(CountBean cb){ :Pc(DfkS
if(cb!=null){ }4Zkf<#7$
list.add(cb); I,]J=xi
} 0Yp>+:#
} 04~}IbeJ
} '(tj[&aL
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CountControl.java X6'H`E[
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/* alVdQfu
* CountThread.java >:A<"wZ
* as(; ]
* Created on 2007年1月1日, 下午4:57 \Yd4gaY\o
* ;uK";we
* To change this template, choose Tools | Options and locate the template under *<7l!#
* the Source Creation and Management node. Right-click the template and choose g@Ld"5$^2
* Open. You can then make changes to the template in the Source Editor. d @m\f
*/ bf1)M>g,O
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package com.tot.count; qIz}$%!A
import tot.db.DBUtils; mf$Sa58
import java.sql.*; g
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/**
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* i@XB&;*c\
* @author &~'S)Nun
*/ i *'Z3Z)
public class CountControl{ S!`:E
private static long lastExecuteTime=0;//上次更新时间 VNO'="U
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 \X5 3|Y;=
/** Creates a new instance of CountThread */ VtWT{y5Ec
public CountControl() {} _W}(!TKO
public synchronized void executeUpdate(){ R#ya,L
Connection conn=null; TU%bOAKF\
PreparedStatement ps=null; 2[ksi51y
try{ NZ+7p{&AN
conn = DBUtils.getConnection(); sDX/zF6t
conn.setAutoCommit(false); -R :X<eb
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); "b`7[ ;a
for(int i=0;i<CountCache.list.size();i++){ ]
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CountBean cb=(CountBean)CountCache.list.getFirst(); &atyDFJ'
CountCache.list.removeFirst(); Q(e{~
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ps.setInt(1, cb.getCountId()); O5M2`6|As
ps.executeUpdate();⑴ D#ZPq,f
//ps.addBatch();⑵ J+|/-{g
} YQYX,b
//int [] counts = ps.executeBatch();⑶ JCD?qeTg
conn.commit(); Z%OW5]q
}catch(Exception e){ e}e6r3faz
e.printStackTrace(); {yS;NU`2
} finally{ WFem#hq
try{ 7E\g
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if(ps!=null) { 8ljuc5,J
ps.clearParameters(); uFo/s&6K
ps.close(); lm*g Gy1i
ps=null; 2T?TM! \Q
} zqf[Z3
}catch(SQLException e){} o,*=$/or
DBUtils.closeConnection(conn); x6v,lR
} m8+:=0|$
} 8SZK:VE@
public long getLast(){ [S0mY["
return lastExecuteTime; :3O5ET'1
} KUFz:&wK
public void run(){ ^BiPLQ
long now = System.currentTimeMillis(); n]iyFZ`9
if ((now - lastExecuteTime) > executeSep) { %J!NL0x_
//System.out.print("lastExecuteTime:"+lastExecuteTime); + {e`]t>_
//System.out.print(" now:"+now+"\n"); nmg{%P
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); c]NN'9G!{
lastExecuteTime=now; #)]E8=}
executeUpdate(); , D"]y~~I5
} (:n|v%
else{ #w|5jN?
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); dlR_ckp
} Zi*%*nX
} qnXTNs
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} |IN[uQ
//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 n}q$f|4!
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类写好了,下面是在JSP中如下调用。 =)
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<% P,ydt
CountBean cb=new CountBean(); I .P6l*$
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); NbkK&bz
CountCache.add(cb); ;A"\?i Q
out.print(CountCache.list.size()+"<br>"); dp<$Zw8BE
CountControl c=new CountControl(); vBoO'l9'M
c.run(); 9yL6W'B!
out.print(CountCache.list.size()+"<br>"); \=fh-c(J,
%>