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: e&Y0}oY
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CountBean.java =y ]Jl,_.
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/* Ry;$^.7%
* CountData.java qV1O-^&[f=
* O_@2;iD^^
* Created on 2007年1月1日, 下午4:44 T(X:Yw
* GrEs1M1]*
* To change this template, choose Tools | Options and locate the template under IY(h~O
* the Source Creation and Management node. Right-click the template and choose `{<frB@
* Open. You can then make changes to the template in the Source Editor. pck >;V
*/ Qez SJ
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package com.tot.count; ^i%A7pg
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/** 3*S[eqMJc
* @Z(rgF{{
* @author ~&G4)AM
*/ $`Nd?\$
public class CountBean { /F[+13C
private String countType; tn<6:@T
int countId; 0LVE@qEL
/** Creates a new instance of CountData */ #Fd W/y5
public CountBean() {} oN2=DYC41
public void setCountType(String countTypes){ iSp
this.countType=countTypes; e=f .y<
} 8:;#,Urr
public void setCountId(int countIds){ nnCug
this.countId=countIds; 6XUuGxQV/
} ``4wX-y
public String getCountType(){ +H'\3^C-
return countType; ^[# &
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} WO</Q6+
public int getCountId(){ 2wpjU&8W!
return countId; a0_(eO-S
} )*1.eObhL
} )qM|3],
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CountCache.java |"k&fkS$
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/* x!{
* CountCache.java 0Oxz3r%}r
* CmC0k-%w
* Created on 2007年1月1日, 下午5:01 b](o]O{v
* D!FaE N
* To change this template, choose Tools | Options and locate the template under ym%slg
* the Source Creation and Management node. Right-click the template and choose Df=q-iq<{/
* Open. You can then make changes to the template in the Source Editor. TQ9'76INb
*/ Ek .3
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package com.tot.count; uDG+SdyN@
import java.util.*; )s")y
/** &sOM>^SAD
* av' *u
* @author Wc'Ehyi;
*/ vZjZb(jlN
public class CountCache { : }?{@#Z
public static LinkedList list=new LinkedList(); ZlR!s!vv
/** Creates a new instance of CountCache */ #}o<v|;
public CountCache() {} 'Ji+c
public static void add(CountBean cb){ i ^|@"+
if(cb!=null){ 4,}GyVJFb`
list.add(cb); MV936
} I-:`cON=G
} Vewzo1G2
} y4F^|kS) [
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CountControl.java 'h*Zc}Q:
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/* :m`/Q_y"
* CountThread.java gue(C(~.k_
* 1L[S*X
* Created on 2007年1月1日, 下午4:57 Yo2Trh
* )!-S|s'
* To change this template, choose Tools | Options and locate the template under ~775soN
* the Source Creation and Management node. Right-click the template and choose {'~sS
* Open. You can then make changes to the template in the Source Editor. ,IjdO(?TC
*/ vjTwv+B"
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package com.tot.count; &'O?es|Lb
import tot.db.DBUtils; nFXAF!,jj
import java.sql.*; !<Z{@7oH
/** :kp0EiJ
* f5?hnt`m
* @author ?)cJZ>$!w
*/ 0xBY(#;Q
public class CountControl{ R<g =\XO'y
private static long lastExecuteTime=0;//上次更新时间 QkX@QQT?
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 Kym:J \}9B
/** Creates a new instance of CountThread */ [ X|OrRA
public CountControl() {} FmA-OqEpA
public synchronized void executeUpdate(){ .BL:h&h|y
Connection conn=null; raQYn?[
PreparedStatement ps=null; Nmf#`+7gCI
try{ <nA3Sd"QfV
conn = DBUtils.getConnection(); AQ}l%
conn.setAutoCommit(false); 3wNN<R
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 4(m3c<'P
for(int i=0;i<CountCache.list.size();i++){ f[@#7,2~M
CountBean cb=(CountBean)CountCache.list.getFirst(); :&$Xe1)i]
CountCache.list.removeFirst(); "jGe^+9uT
ps.setInt(1, cb.getCountId()); tc/ jY]'32
ps.executeUpdate();⑴ dofR)"<p,^
//ps.addBatch();⑵ Mf7E72{D
} l$`G:%qHj
//int [] counts = ps.executeBatch();⑶ :yD@5)
conn.commit(); c~oe,9
}catch(Exception e){ s5.k|!K
e.printStackTrace(); Wf1-"Q
} finally{ y''V"Be
try{ <4NQL*|>
if(ps!=null) { zjWyGt(Q
ps.clearParameters(); }85#[~m'
ps.close(); ^'Zh;WjI7
ps=null; SRk7gfP*q
} r %xB8e9
}catch(SQLException e){} YPQCOG
DBUtils.closeConnection(conn); ~%G Ssm\J
}
* D3
} WFdem/\kX
public long getLast(){ Prt#L8
return lastExecuteTime; JWSq"N
} gT7I9 (x!W
public void run(){ $y4M#yv
long now = System.currentTimeMillis(); :+A;TV
if ((now - lastExecuteTime) > executeSep) { 9jjL9f_3
//System.out.print("lastExecuteTime:"+lastExecuteTime); zf")|9j
//System.out.print(" now:"+now+"\n"); nP)-Y#`~7
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); m2MPWy5s
lastExecuteTime=now; <^'{ G
executeUpdate(); V9]uFL
} {q2<KRU2+#
else{ 4+,*sn
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); <M>#qd@c
} %>]#vQ|
} =z%s8D2
} @f'AWeJ2
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 ;@O(z*14@
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类写好了,下面是在JSP中如下调用。 ,,2_/u\"/i
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<% qZc)Sa.S
CountBean cb=new CountBean(); gU*I;s>
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); > hesxC!
CountCache.add(cb); CY\mU_.b
out.print(CountCache.list.size()+"<br>"); y7
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CountControl c=new CountControl(); /^WE@r[:
c.run(); '|+=B u
out.print(CountCache.list.size()+"<br>"); .Px,=56$X
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