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: i(.c<e{v~
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CountBean.java 8>q:Q<BB2
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/* Ycb<'M*jE
* CountData.java TSu^.K
* $$YLAgO4
* Created on 2007年1月1日, 下午4:44 4/D~H+k
* G3QB Rh{
* To change this template, choose Tools | Options and locate the template under Q"c!%`\
* the Source Creation and Management node. Right-click the template and choose -eAo3
* Open. You can then make changes to the template in the Source Editor. g;en_~g3j
*/ K]dqK'
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package com.tot.count; 0^44${bA
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/** J{72%S
* 'R6D+Vk/
* @author @'[w7HsJ
*/ QI>yi&t
public class CountBean { jeb<qi>
private String countType; F=
int countId; |E@G sw
/** Creates a new instance of CountData */ JA7HO|
public CountBean() {} &|<~J(L;
public void setCountType(String countTypes){ .UbmU^y|
this.countType=countTypes; vj0`[X
} M"F?'zTkJ
public void setCountId(int countIds){ #f]R:Ix>
this.countId=countIds; gUDd2T#
} GV)#>PL
public String getCountType(){ e1{t qNJ
return countType; bj`cYL%
} ]!H*oP8a*
public int getCountId(){ ,
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return countId; THQW8 V
} l ,)l"6OV
} {B|U8j[
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CountCache.java G~)jk+Qq
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/* `< y[V
* CountCache.java 18w[T=7)
* Zx25H"5j
* Created on 2007年1月1日, 下午5:01 Faa:h#
* t&SJ!>7_c
* To change this template, choose Tools | Options and locate the template under uR)itmc?
* the Source Creation and Management node. Right-click the template and choose 'xZxX3
* Open. You can then make changes to the template in the Source Editor. # l~d
*/ ,: w~-
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package com.tot.count; O89<IXk
import java.util.*; P>euUVMPz4
/** 9In&vF7$
* H_;Dq*
* @author 'N=' B<^;%
*/ eFXxkWR)
public class CountCache { KtY~Y
public static LinkedList list=new LinkedList(); M@!Gk
/** Creates a new instance of CountCache */ ]Ke|wRQD
public CountCache() {} k}>l+_*+7
public static void add(CountBean cb){ 05*_h0}
if(cb!=null){ 'DsfKR^s
list.add(cb); &0f7>.y
} 2bX!-h
} Tv3 ZNh
} doc5;?6
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CountControl.java EN.yU!N.4
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/* w,8 M
* CountThread.java ] >ipC,v
* Djf2ir'
* Created on 2007年1月1日, 下午4:57 dG7sY
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* ~\<ZWU<BE
* To change this template, choose Tools | Options and locate the template under ^.kas7<
* the Source Creation and Management node. Right-click the template and choose qa^x4xZM
* Open. You can then make changes to the template in the Source Editor. ;~~Oc
*/ a,cDj
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package com.tot.count; R$,`}@VqZ3
import tot.db.DBUtils; nq/xD;q
import java.sql.*; ?0[%+AD hM
/** AG}'
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* ZM;EjS1
* @author [$[t.m
*/ ieBW 0eMi
public class CountControl{ >;xEzc!W3*
private static long lastExecuteTime=0;//上次更新时间 rF~q"9
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 +*0THol-
/** Creates a new instance of CountThread */ |&n dQ(!l
public CountControl() {} AaTtYd
public synchronized void executeUpdate(){ O-T/H-J`
Connection conn=null; n^&QOII@>
PreparedStatement ps=null; R~RY:[5?w
try{ *kyy''r
conn = DBUtils.getConnection(); 8" 8{Nf-"
conn.setAutoCommit(false); xDADJ>u2K
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); mSQ!<1PM
for(int i=0;i<CountCache.list.size();i++){ yvDzxu
CountBean cb=(CountBean)CountCache.list.getFirst(); 4vqu(w8
L
CountCache.list.removeFirst(); R<UjhCvx.
ps.setInt(1, cb.getCountId()); aE{b65'Dt
ps.executeUpdate();⑴ "6KOql3
//ps.addBatch();⑵ Cc Ni8Wg_
} sef!hS06
//int [] counts = ps.executeBatch();⑶ 't)j
conn.commit(); fE7WLV2I>
}catch(Exception e){ 8-?n<h%8E
e.printStackTrace(); dJ24J+9}]j
} finally{ ixKQh};5/
try{ 4zf#zJw
if(ps!=null) { H8\{GGg
ps.clearParameters(); fI$,?>
ps.close(); |?8CV\D!
ps=null; Q ;k_q3
} +#B%Y K|LR
}catch(SQLException e){} A5H[g`&
DBUtils.closeConnection(conn); 3J,/bgL5
} *c3o&-ke9
} 9 oq(5BG,
public long getLast(){ cQ+,F2
return lastExecuteTime; :He:Bdk
} /=r&9P@Ay<
public void run(){ \17)=W
long now = System.currentTimeMillis(); n.1a1 Tf
if ((now - lastExecuteTime) > executeSep) { V|a59[y?
//System.out.print("lastExecuteTime:"+lastExecuteTime); b/5~VY*T
//System.out.print(" now:"+now+"\n"); tQl=
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); q0c)pxD%`
lastExecuteTime=now; i;dr(c/ft
executeUpdate(); X 4/r#<Da
} =~EQ3uX
else{ YYM
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); (U.&[B
} O0$ijJa|
} hR`dRbBi%
} R>0ta
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//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 ?1412Tq5
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类写好了,下面是在JSP中如下调用。 rW6w1
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<% a9qZI
CountBean cb=new CountBean(); g)p[A 4
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); %##9.Xm6l
CountCache.add(cb); 1^W Aps
out.print(CountCache.list.size()+"<br>"); Bkz
CountControl c=new CountControl(); JGdBpj:
c.run(); 9a4RW}S<
out.print(CountCache.list.size()+"<br>"); ;zJ_apZ:{
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