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: LYECX
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CountBean.java @i!+Z
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/* @3KSoA"^
* CountData.java )VkVZf | S
* 6Q7=6
* Created on 2007年1月1日, 下午4:44 nt$PA(Y
* dxAGO(
* To change this template, choose Tools | Options and locate the template under ,$:u^;V(
* the Source Creation and Management node. Right-click the template and choose k-
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* Open. You can then make changes to the template in the Source Editor. nMzt_Il I
*/ Hq 5#.rZ#
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package com.tot.count; 4;J.$
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/** DZ2gnRg
* 5X)QW5A
* @author ~Ze!F"
*/ IF6$@Q
public class CountBean { -d'FKOD
private String countType; M?sax+'
int countId; :?zq!
/** Creates a new instance of CountData */ z0/+P
public CountBean() {} Z40k>t
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public void setCountType(String countTypes){ nc:/GxP
this.countType=countTypes; 0SYJ*7lPX
} S?JCi=
public void setCountId(int countIds){ KPO w
this.countId=countIds; /kG?I_z
} rtz-kQ38R
public String getCountType(){ N.q~\sF^
return countType; #)7`}7N
} =@M9S
public int getCountId(){ b'+Wf#.]f0
return countId; Yv]vl6<
} VVch%
} BedL `[,
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CountCache.java "rLm)$I
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/* v\6.#>NQ
* CountCache.java F]6G<6T[
* I2CI9,0
* Created on 2007年1月1日, 下午5:01 jy.L/s
* 5}hQIO&^%
* To change this template, choose Tools | Options and locate the template under O713'i
* the Source Creation and Management node. Right-click the template and choose ,jC~U s<
* Open. You can then make changes to the template in the Source Editor. )uHat#
*/ [>?|wQy >=
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package com.tot.count; @-S7)h>~
import java.util.*; Fz(;Eo3
/** N\ Mdia
* 18%$Z$K,
* @author A,EG0yb
*/ 8Gy]nD
public class CountCache { @4*eH\3
public static LinkedList list=new LinkedList(); vzI>:Bf
/** Creates a new instance of CountCache */ ,)xtl`fc
public CountCache() {} Ne|CWUhO
public static void add(CountBean cb){ $!9U\Au>2
if(cb!=null){ h\@X!Z,
list.add(cb); 3lWGa7<4Z
} >g!$H}\
} }GURq#
} <Rw2F?S~)n
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CountControl.java $m5Iv_
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/* dLH@,EKl)
* CountThread.java GPh;r7xg6
* h!(#
/
* Created on 2007年1月1日, 下午4:57 6)YckxN^
* v2]N5
* To change this template, choose Tools | Options and locate the template under ?SYmsaSr5
* the Source Creation and Management node. Right-click the template and choose ,x&WE@tD|
* Open. You can then make changes to the template in the Source Editor. @*xP A
*/ I_8 n>\u
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package com.tot.count; WP\kg\o
import tot.db.DBUtils; j7g>r/1eE
import java.sql.*; 7CR#\&h`
/** +pq=i
* .R`_"7
* @author aU.3
*/ sqhIKw@
public class CountControl{ 63\
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private static long lastExecuteTime=0;//上次更新时间 fI;nVRfp
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 r\fkx>
/** Creates a new instance of CountThread */ [Y`E"1f2
public CountControl() {} lQ^"-zO4
public synchronized void executeUpdate(){ <^>
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Connection conn=null; ~u0<c:C^
PreparedStatement ps=null; /<T{g0s
try{ VSUWX1k4%
conn = DBUtils.getConnection(); gA EB
conn.setAutoCommit(false); w$&;s<0
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); .u&X:jOE
for(int i=0;i<CountCache.list.size();i++){ =[aiW|Y
CountBean cb=(CountBean)CountCache.list.getFirst(); :##$-K*W"
CountCache.list.removeFirst(); y]R+/
ps.setInt(1, cb.getCountId()); PyI"B96gz
ps.executeUpdate();⑴ voRb>xF
//ps.addBatch();⑵ g51UIN]o-
} Zp{K_ec{
//int [] counts = ps.executeBatch();⑶ B)DuikV.D
conn.commit(); tIV9Y=ckr0
}catch(Exception e){ vAG|Y'aO@%
e.printStackTrace(); I+Yq",{%
} finally{ c]k+ Sx&}
try{ Y#9bM$x7
if(ps!=null) { mDA+
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ps.clearParameters(); 45-x$o
ps.close(); L"1AC&~u
ps=null; =`(W^&|
} 6j1C=O@S
}catch(SQLException e){} 0r$n
DBUtils.closeConnection(conn); \uo{I~Qd
} Ed0}$b
} ]!"7k_
public long getLast(){ j7I?K
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return lastExecuteTime; kene'
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} ,V5fvHPH)8
public void run(){ #$U/*~m $
long now = System.currentTimeMillis(); ^pY8'LF6
if ((now - lastExecuteTime) > executeSep) { +:aNgO#e8
//System.out.print("lastExecuteTime:"+lastExecuteTime); a)S6Z
//System.out.print(" now:"+now+"\n"); x3 ( _fS
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ep5`&g]3
lastExecuteTime=now; ^(T~ Q p
executeUpdate(); [q0^Bn}h
} QS4~":D/C
else{ S~m8j|3K
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); nRX'J5Q
m<
} (u@X5O(a
} k`' *niz
} 2Kr8#_) 0
//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 7;.Iat9gMf
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类写好了,下面是在JSP中如下调用。 fWIWRsy%
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<% X<W${L$G
CountBean cb=new CountBean(); 4%<wxrod
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); G[`2Nd<
CountCache.add(cb); PD^ 6Ywn>s
out.print(CountCache.list.size()+"<br>"); eq"Xwq*
CountControl c=new CountControl(); vqoK9
c.run(); 8ZjRMr}
out.print(CountCache.list.size()+"<br>"); `{IL.9M!f
%>