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: 1+-F3ROP
u7-0?
CountBean.java _$v$v$74^
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/* xCMuq9zt@
* CountData.java 1z3I^gI*i
* l_(4CimOZ
* Created on 2007年1月1日, 下午4:44 |D8c=c%
* g$8aB{)
* To change this template, choose Tools | Options and locate the template under "azrcC
* the Source Creation and Management node. Right-click the template and choose O)r>AdLGn
* Open. You can then make changes to the template in the Source Editor. i^/H>E%u
*/ [U{RDX
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package com.tot.count; ^Ux*"\/Es
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/** +jp^
* ur
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* @author ` $[`C/h
*/ [+:KIW<
public class CountBean { r\|"j8
private String countType; XP65
int countId; ";59,\6
/** Creates a new instance of CountData */ u?8e>a
public CountBean() {} puGy`9eKv1
public void setCountType(String countTypes){ -} +PE 4fh
this.countType=countTypes; !i=k=l=
} ,Lw
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public void setCountId(int countIds){ Uq2 Qh@B
this.countId=countIds; &MP8.(u `
} ~I%JVX%
public String getCountType(){ P"c7h7
return countType; H3S u'3
} *Rj*%S
public int getCountId(){ hhOrO<(
return countId; e#4 iue7U
} !|#1z}(
} H, O_l%
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CountCache.java r$Y% 15JV
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/* jyjK~!0
* CountCache.java h,'m*@Eg
* }sGH}n<9*
* Created on 2007年1月1日, 下午5:01 i(<do "Am<
* 8f#&CC!L
* To change this template, choose Tools | Options and locate the template under 6z+*H7Qz
* the Source Creation and Management node. Right-click the template and choose ;#?+i`9'q
* Open. You can then make changes to the template in the Source Editor. f@IL2DL}\
*/ (( Wq
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package com.tot.count; qd?k#Gw&
import java.util.*; {7o|*M
/** [2ZZPY9?Q
* c::Vh
* @author ekuRGG
*/ +JL"Z4b@R}
public class CountCache { g ??@~\Ov
public static LinkedList list=new LinkedList(); `)eqTeW
/** Creates a new instance of CountCache */ C$EvcF%1
public CountCache() {} %g%#=a;]q
public static void add(CountBean cb){ RIxGwMi%
if(cb!=null){ @Tf5YZ*
list.add(cb); XZ&q5]PJI
} {2%@I~US
} _{'HY+M
} !8>tT
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CountControl.java YPsuG -is
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/* :. a}pgh
* CountThread.java 1:lhZFZ
* v#`P?B\
* Created on 2007年1月1日, 下午4:57 s&zg!~@5b
* cwA+?:Ry}
* To change this template, choose Tools | Options and locate the template under p[-buB]
* the Source Creation and Management node. Right-click the template and choose EK}f-Xei
* Open. You can then make changes to the template in the Source Editor. DvvjIYB~
*/ u-E*_%y
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package com.tot.count; g4*]R>f
import tot.db.DBUtils; 20H$9M=}
import java.sql.*; vZpt}u
/** W%RjjLJ@
* { sL(PS.z
* @author ? k*s!YCZ
*/ O
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public class CountControl{ Y:XxTa*
private static long lastExecuteTime=0;//上次更新时间 `l95I7
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 A?*_14&
/** Creates a new instance of CountThread */ .pQ4#AJ
public CountControl() {} &llp*<
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public synchronized void executeUpdate(){ 9rsty{J8
Connection conn=null; h $}&N
PreparedStatement ps=null; j*jO809%^
try{ I 0}+}{M:
conn = DBUtils.getConnection(); E6d0YgfD
conn.setAutoCommit(false); t,K_!-HX+
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); HLcK d`$/
for(int i=0;i<CountCache.list.size();i++){ &Q"Ox{~W
CountBean cb=(CountBean)CountCache.list.getFirst(); '\X<+Sm'
CountCache.list.removeFirst(); ef=LPCi?
ps.setInt(1, cb.getCountId()); VZ8HnNAbX
ps.executeUpdate();⑴ Ni[2 p
//ps.addBatch();⑵ s9Aq-N
} Yxt`Uvc(^h
//int [] counts = ps.executeBatch();⑶ YQ}bG{ V
conn.commit(); Iz\IQa
}catch(Exception e){ PO[
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e.printStackTrace(); M[R\URu8
} finally{ !fcr3x|Y~M
try{ 1[vmK,N=E
if(ps!=null) { @OlV6M;qJ
ps.clearParameters(); w%[`'_[
ps.close(); T7=~l)I
ps=null; agFWye
} I)Dd"I
}catch(SQLException e){} lT3, G#(
DBUtils.closeConnection(conn); "p~1|?T
} ~cSOni`
} s:y=X$&M
public long getLast(){ *a7&v3X
return lastExecuteTime; u@$C i/J*
} 'i|z>si[*
public void run(){ iVt*N$iZ
long now = System.currentTimeMillis(); 7usf^g[dh
if ((now - lastExecuteTime) > executeSep) { \P_1@sH=
//System.out.print("lastExecuteTime:"+lastExecuteTime); =%YU~
//System.out.print(" now:"+now+"\n"); "$tP>PO{<
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); `\:92+
lastExecuteTime=now; X|F([,o
executeUpdate(); 'o2x7~C@
} bqxbOQd
else{ p`3pRrER
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); }w&+H28.#
} t YmR<^
} ?2;r#)
} E,nC}f
//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)NQK9~
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类写好了,下面是在JSP中如下调用。 F.b;O :
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<% X'Dg= |
CountBean cb=new CountBean(); EF?@f{YY$n
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); qsUlfv9L6
CountCache.add(cb); 7
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out.print(CountCache.list.size()+"<br>"); \KmjA)(
CountControl c=new CountControl(); eGS1% [
c.run(); Y
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out.print(CountCache.list.size()+"<br>"); 37 wm[Z
%>