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: m.FN ttkM
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CountBean.java hC4
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/* JS/~6'uB
* CountData.java oB(9{6@N
* #O{cplh,
* Created on 2007年1月1日, 下午4:44 c!GJS`/
* p=V1M-
* To change this template, choose Tools | Options and locate the template under 1vYa&!
* the Source Creation and Management node. Right-click the template and choose 26p_fKY
* Open. You can then make changes to the template in the Source Editor. H<tU[U=G
*/ "xNP"S
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package com.tot.count; 6tGF
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/** wq|7sk{
* &dPI<HlM
* @author N85ZbmU~
*/ FNs$k=*8
public class CountBean { U02
private String countType; FOhq&\nkU
int countId; qDcoccEf
/** Creates a new instance of CountData */ $b[Ha{9(v
public CountBean() {} R8 LHwRQ
public void setCountType(String countTypes){ Jl1\*1"
this.countType=countTypes; n5#QQk2
} hj\A-Yf
public void setCountId(int countIds){ bYmk5fpRG
this.countId=countIds; pgs<Mo$\%B
} T7-yZSw-m
public String getCountType(){ Dw>)\\n{Kl
return countType; QQ=Kj%R
} <\$?.tTZ{
public int getCountId(){ &Xc=PQ:I
return countId; IgRi(q^b-
} P4LiU2C
} bM2x
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CountCache.java MEM(uBYKOb
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/* ,J=l Hj
* CountCache.java l;$FR4}d
* =q>lP+
* Created on 2007年1月1日, 下午5:01 ,M:[GuXD<
* NV==[$ (r
* To change this template, choose Tools | Options and locate the template under Uw| -d[!
* the Source Creation and Management node. Right-click the template and choose FAdTp.
* Open. You can then make changes to the template in the Source Editor. aPRMpY-YC3
*/ / U!xh3
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package com.tot.count; "3'a.b akw
import java.util.*; J*_^~t
/** S<jiy<|`
* `sA xk
* @author 'blMwD{0&\
*/ AAqfp/DC
public class CountCache { B%`|W@v
public static LinkedList list=new LinkedList(); ]+b?J0|P<
/** Creates a new instance of CountCache */ ,Vl2U"
public CountCache() {} `[e0_g\
public static void add(CountBean cb){ =$%-RX7
if(cb!=null){ v
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list.add(cb);
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} -d thY(8
} 9g#
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} b~B'FD
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CountControl.java /q8B | (U
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/* 0:-z+`RHE
* CountThread.java ';}:*nZ//_
* 5s;@ ;V
* Created on 2007年1月1日, 下午4:57 C(UWir3mW?
* !Pt4\
* To change this template, choose Tools | Options and locate the template under @4KKm@(p85
* the Source Creation and Management node. Right-click the template and choose w
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* Open. You can then make changes to the template in the Source Editor. qu!x#OY+
*/ 9I`0`o"A
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package com.tot.count; <f =<r*6
import tot.db.DBUtils; O3)B]!xL
import java.sql.*; hsJ^Au=})w
/** 6G#[Mc yn
* `t44.=%
* @author \Ui8gDJ8y5
*/ )T? BO
public class CountControl{ (D6ks5Uui
private static long lastExecuteTime=0;//上次更新时间 4sX?O4p
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 -m[ tYp,q
/** Creates a new instance of CountThread */ xA<-'8ST
public CountControl() {} kM@e_YtpY
public synchronized void executeUpdate(){ bxO[y<|XL
Connection conn=null; :'xZF2
PreparedStatement ps=null; k<Xb<U
try{ gPA8A>U)[
conn = DBUtils.getConnection(); \gK'g-)}
conn.setAutoCommit(false); xwW(WHdC]
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); !I\eIV>0b
for(int i=0;i<CountCache.list.size();i++){ P: L6Zo-J
CountBean cb=(CountBean)CountCache.list.getFirst(); |eg8F$WU
CountCache.list.removeFirst(); Ut C<TBr
ps.setInt(1, cb.getCountId()); PW iuM=E
ps.executeUpdate();⑴ .:4*HB
//ps.addBatch();⑵ j?T>S]xOX
} BHS@whj
//int [] counts = ps.executeBatch();⑶ vl6|i)D
conn.commit(); }}u`*&,g
}catch(Exception e){ &;WK=#
e.printStackTrace(); S,udpQ7
} finally{ U>00B|<GJ
try{ kGC*\?<LmR
if(ps!=null) { >wL!`:c'"
ps.clearParameters(); "=KFag
ps.close(); MRZN4<}9
ps=null; t-n'I/^5
} Nf2lw]-G4
}catch(SQLException e){} 7xY&7 x(v
DBUtils.closeConnection(conn); dd;rnev+
} Vq/hk
} 1|s`z
public long getLast(){ +fKV/tSWi
return lastExecuteTime; ;8
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} ;CoD5F!
public void run(){ __1Hx?f
long now = System.currentTimeMillis(); \TnK<83
if ((now - lastExecuteTime) > executeSep) { {X<_Y<
//System.out.print("lastExecuteTime:"+lastExecuteTime); ;Jb%2?+=!
//System.out.print(" now:"+now+"\n"); PMX'vA`
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 2P${5WT
lastExecuteTime=now; b"`Q&V.
executeUpdate(); ke KsLrd
} H#WqO<<v
else{ X+HPdrT
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 6' \M:'<0e
} 3u 7A(
} j|qdf3^f
} U#sv.r/L}3
//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 W5()A,R
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类写好了,下面是在JSP中如下调用。
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<% WP Gp(Xw
CountBean cb=new CountBean(); E7.{SGH}
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); \d:Uq5d)0
CountCache.add(cb); O<mA+yk
out.print(CountCache.list.size()+"<br>"); C
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CountControl c=new CountControl(); Fi 7~JZZ
c.run(); R<hsG%BS(D
out.print(CountCache.list.size()+"<br>"); O*N:.|dUw
%>