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: )B,|@ynu
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CountBean.java lKZB?Kk^w\
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/* ,to+oSZE
* CountData.java M])dJ9&e
* Mj[f~
* Created on 2007年1月1日, 下午4:44 M" ^PW,k
* J]f3CU,<N
* To change this template, choose Tools | Options and locate the template under iu&wO<)+?
* the Source Creation and Management node. Right-click the template and choose 4vBL6!z:Z
* Open. You can then make changes to the template in the Source Editor. >h0-;
*/ m3Il3ZY.
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package com.tot.count; 4jD2FFG-
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/** jck}" N
* 2^i(gaXUQ
* @author ]?*I9
*/ .tD*2
public class CountBean { |2{wG4
private String countType; g=I8@m
int countId; sc,Xw:YO
/** Creates a new instance of CountData */ e=O,B8)_
public CountBean() {} x c{hC4^V
public void setCountType(String countTypes){ pb~pN
this.countType=countTypes; "etPT@gF
} w^t/9Nasi
public void setCountId(int countIds){ XQw>EZdj_N
this.countId=countIds; lok=
} g) -bW+]q
public String getCountType(){ 9-MUX^?u
return countType; T#>7ub
} YpqrZWvh
public int getCountId(){ kh`"WN Nt
return countId; x&0vKo;
} fk&8]tK4
} t<#h$}=:Vt
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CountCache.java ;3@cy|\:
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/* >D4#y
* CountCache.java ;n
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* pej|!oX
* Created on 2007年1月1日, 下午5:01 4qk9NK2 U
* #)nSr
* To change this template, choose Tools | Options and locate the template under cI4K+
* the Source Creation and Management node. Right-click the template and choose t;}:waZD
* Open. You can then make changes to the template in the Source Editor. ?U2<
*/ P(f0R8BE
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package com.tot.count; rogT~G}q
import java.util.*; LA}Syt\F
/** 9J2NH|]c
* fSokm4]vg
* @author 6|PrX
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*/ V T\F]Oa#
public class CountCache { QD0"rxZJ
public static LinkedList list=new LinkedList(); TOB]IrW
/** Creates a new instance of CountCache */ ;5659!;
public CountCache() {} 24z< gO
public static void add(CountBean cb){ ?j"KV_
if(cb!=null){ u=`L)
list.add(cb); '/^qJ7eb
} *GL/aEI<$
} xLK<W"%0
} [PNT\ElT
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CountControl.java VHIOwzC
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/* @$[?z9ck"
* CountThread.java 1;Ou7T9w
* n>BkTaI
* Created on 2007年1月1日, 下午4:57 2N: ,Q8~
* %C|n9*
* To change this template, choose Tools | Options and locate the template under J IUx
* the Source Creation and Management node. Right-click the template and choose wl#@lOv-P
* Open. You can then make changes to the template in the Source Editor. DtXrWS/
*/ fF7bBE)L/|
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package com.tot.count; }fb#G<3
import tot.db.DBUtils; K,+LG7ec
import java.sql.*; ~*z% e*EL
/** 4T|b
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* %4et&zRC
* @author _>(^tCo
*/ ,,%i;
public class CountControl{ J8uLJ
private static long lastExecuteTime=0;//上次更新时间 kMi/>gpQ
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 u0|8Tgf
/** Creates a new instance of CountThread */ .HS"}A T
public CountControl() {} GpY"fc%
public synchronized void executeUpdate(){ q&s3wDl/
Connection conn=null; X[]m _@ v
PreparedStatement ps=null; &"f";
try{ *|%@6I(
conn = DBUtils.getConnection(); *W,]>v0%T
conn.setAutoCommit(false); :61Tun
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ,k )w6)
for(int i=0;i<CountCache.list.size();i++){ _}lZ,L(w
CountBean cb=(CountBean)CountCache.list.getFirst(); \F1_lq;K
CountCache.list.removeFirst(); t<#mP@Mz=N
ps.setInt(1, cb.getCountId()); ?pr9f5
ps.executeUpdate();⑴ ^t` k0<
//ps.addBatch();⑵ S%bCyK%p
} I4/8 _)b^
//int [] counts = ps.executeBatch();⑶ ;X?}x%$
conn.commit(); ^U
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}catch(Exception e){ hn5h\M?
e.printStackTrace(); 0h#lJS*
} finally{ GPkmf%FJ
try{ -I*^-+>H
if(ps!=null) { Y2a5bc P
ps.clearParameters(); .`HYA*8_
ps.close(); ]op}y0
ps=null; fol,xMc&
} \Jx04[=
}catch(SQLException e){} *W.C7=
DBUtils.closeConnection(conn); %eX{WgH
} S>h;K`
} 3LAIl913
public long getLast(){ tjIl-IQ
return lastExecuteTime; $bW3_rl%X
} "@%7 -nu
public void run(){ Huy5-[)15
long now = System.currentTimeMillis(); }Mst jm
if ((now - lastExecuteTime) > executeSep) { $;1#To
//System.out.print("lastExecuteTime:"+lastExecuteTime); "S8uoSF`>
//System.out.print(" now:"+now+"\n"); (}{G`N>.{
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ^N7e76VwR
lastExecuteTime=now; PPb7%2r
executeUpdate(); pOGeruu?
} ?3nR
else{ \]</w5 Pi,
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); I KqQ>Z-q~
} 4]yOF_8h
} &+cEV6vb+
} YM1'L\^
//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 p2ogn}`
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类写好了,下面是在JSP中如下调用。 wb]%m1H`:
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<% :yRo3c
CountBean cb=new CountBean(); kO,zZF&
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); )k\H@Dy%$
CountCache.add(cb); kW*f.!
out.print(CountCache.list.size()+"<br>"); dYG,_ji
CountControl c=new CountControl(); S0B|#O%Z
c.run(); =T-&j60
out.print(CountCache.list.size()+"<br>"); +b.g$CRr
%>