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: + Z2<spqG
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CountBean.java G$uOk?R#5c
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/* Kg-X]yu*0
* CountData.java IF}c*uGj}
* l0xFt
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* Created on 2007年1月1日, 下午4:44 LlY*r+Cgl1
* 8lSn*;S,
* To change this template, choose Tools | Options and locate the template under /C2f;h(1
* the Source Creation and Management node. Right-click the template and choose WTs[Sud/
* Open. You can then make changes to the template in the Source Editor. UDtbfc7bk
*/ \&)W#8V
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package com.tot.count; 8Flf,"a
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/** v/.h%6n?
* &})d%*n
* @author U*"cf>dB(
*/ i/~QJ1C
public class CountBean { h^ $}1[
private String countType; 2BA9T nxC
int countId; 1y-lZ}s_
/** Creates a new instance of CountData */ aW-o=l@;
public CountBean() {} EFt`<qwj
public void setCountType(String countTypes){ <`UG#6z8
this.countType=countTypes; C_ZD<UPA\
} 15o
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public void setCountId(int countIds){ ,Ysl$^\
this.countId=countIds; ,T*_mDVY
} L^{;jgd&T9
public String getCountType(){ $_zkq@
return countType; mKQST ]5
} fB,1s}3Hn
public int getCountId(){ :_,]?n
return countId; "u8o?8+q~
} i)PV{3v$J
} EZumJ."
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CountCache.java O| 6\g>ew
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/* X+E\]X2
* CountCache.java Dke($Jr{
* Yj7= T%5
* Created on 2007年1月1日, 下午5:01 6aZt4Lw2\
* /,N!g_"Z
* To change this template, choose Tools | Options and locate the template under >dvWa-rNUT
* the Source Creation and Management node. Right-click the template and choose Bx : So6:
* Open. You can then make changes to the template in the Source Editor. 'BdmFKy1
*/ oT (:33$
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package com.tot.count; Y!1^@;)^
import java.util.*; Q] yT
/** C6V&R1" s
* X$|TN+Ub
* @author !eAdm
*/ kbp(
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public class CountCache { ={E!8"
public static LinkedList list=new LinkedList(); ml33qXW:
/** Creates a new instance of CountCache */ ^&';\O@)
public CountCache() {} _[vdY|_
public static void add(CountBean cb){ Lr}b,
if(cb!=null){ PUjoi@]
list.add(cb); Ie&b<k
} hp]ng!I{\u
} +fP/|A8P
} 'W?v.W &
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CountControl.java jo;uR l
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/* Ei9_h
* CountThread.java i
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* QTjftcu
* Created on 2007年1月1日, 下午4:57 <V:<x
* x\J;ZiWwW
* To change this template, choose Tools | Options and locate the template under 4$zFR}f
* the Source Creation and Management node. Right-click the template and choose ZkB6bji
* Open. You can then make changes to the template in the Source Editor. zdjM%l);
*/ q
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package com.tot.count; s\Pt,I@Y_
import tot.db.DBUtils; !(]dz~sM
import java.sql.*; B=gsd0^]
/** |j~EV~AJ
* XHZ:
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* @author YD='M.n\
*/ +r-dr>&H@
public class CountControl{ Rg?{?qK\K
private static long lastExecuteTime=0;//上次更新时间 MB8SB
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 #NN"(I
/** Creates a new instance of CountThread */ ^?s~Fk_V
public CountControl() {} ~C"k$;(n
public synchronized void executeUpdate(){ 5Q$r@&qp
Connection conn=null; KM6N'x ^z
PreparedStatement ps=null; 5&?KW)6 Rz
try{ j
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conn = DBUtils.getConnection(); 4P4 Fo1
conn.setAutoCommit(false); O@r.>
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); zY1s7/$i
for(int i=0;i<CountCache.list.size();i++){ =CKuiO.j
CountBean cb=(CountBean)CountCache.list.getFirst(); G !1~i*P$u
CountCache.list.removeFirst(); &>W (l.
ps.setInt(1, cb.getCountId()); LmXF`Y$
ps.executeUpdate();⑴ xMNNXPz(
//ps.addBatch();⑵ xI@$aTGq
} 0;FqX*
//int [] counts = ps.executeBatch();⑶ GDHK.?GY
conn.commit(); q[)q|R|
}catch(Exception e){ f8LrDR
e.printStackTrace(); .|-l+
} finally{ hg?j)jl|
try{ <}EV*`w4
if(ps!=null) { tM^;?HL]
ps.clearParameters(); ~MhgAC
ps.close(); 2JiAd*WK
ps=null; :WK"-v
} _(oP{wgB
}catch(SQLException e){} mvHh"NJ
DBUtils.closeConnection(conn); :Su #xI
} jD '
} JO2ZS6k[
public long getLast(){ 7b&JX'`Mb
return lastExecuteTime; X-)RU?
} .:{h{@a
public void run(){ r=~WMDCz@
long now = System.currentTimeMillis(); 11)/] ?/j
if ((now - lastExecuteTime) > executeSep) { $hjP}- oUX
//System.out.print("lastExecuteTime:"+lastExecuteTime); M&qh]v gC
//System.out.print(" now:"+now+"\n"); 'dIX=/RZ
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); Ml8 YyF/~
lastExecuteTime=now; n+{HNr
executeUpdate(); d ~{jEg
} L$+d.=]
else{ ?$|uT
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); W\@?e32
} 9Z,*h-o
} .D8~)ZWN
} >=-GD2WK
//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 h4CTTe)
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类写好了,下面是在JSP中如下调用。 w]>"'o{{
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<% oA4D\rn8"
CountBean cb=new CountBean(); $!YKZ0)B'0
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); OUEI~b1
CountCache.add(cb); 7FmbV/&c
out.print(CountCache.list.size()+"<br>"); 1Pk mg%+
CountControl c=new CountControl(); =\~E n5
c.run(); r0\cc6
out.print(CountCache.list.size()+"<br>"); ?HrK\f3wWO
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