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: QXrK-&fju
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CountBean.java zbnQCLs
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/* OJK/>
* CountData.java :DD4BY
* [L275]4n!]
* Created on 2007年1月1日, 下午4:44 $p0s
* kju:/kY A
* To change this template, choose Tools | Options and locate the template under MhsG9q_%
* the Source Creation and Management node. Right-click the template and choose 3aOFpCs|#
* Open. You can then make changes to the template in the Source Editor.
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*/ k.0C*3'
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package com.tot.count; ]uZH 0
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/** jlB3BwG{w
* ^KlOD_GN|
* @author h~1QmEat
*/ /t/q$X
public class CountBean { &><`?
private String countType; fx|9*|E
int countId; 4S=lO?\"A
/** Creates a new instance of CountData */ #Z.JOwi
public CountBean() {} RS1oPY
public void setCountType(String countTypes){ '-x%?Ll
this.countType=countTypes; J0oR]eT}
} EAI[J&c
public void setCountId(int countIds){ +2g3%c0}
this.countId=countIds; zPXd]jIwV
} iO@wqbg$6
public String getCountType(){ ^Nu} HcC+
return countType; (UM+?]Qwy
} ?R+$4;iy
public int getCountId(){ Jq!($PdA
return countId; k9,"`dk@
} Y}6)jzBV
} Xu$*ZJ5w
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CountCache.java gu/Yc`S[
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/* |WX4L7yrhK
* CountCache.java i!iODt3k
* v!uLd.(
* Created on 2007年1月1日, 下午5:01 pg<>Ow5,~l
* ,..b)H5n
* To change this template, choose Tools | Options and locate the template under [q@%)F
* the Source Creation and Management node. Right-click the template and choose HfF$>Z'kM
* Open. You can then make changes to the template in the Source Editor. |RmBa'.)z
*/ cBA[D~s
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package com.tot.count; 1-n0"lP~4
import java.util.*; +~@Y#>+./l
/** l\5NuCgRY
* IlrmXSr
* @author ' 4"L;){:L
*/ O^GX Fz^
public class CountCache { s,RS}ek~|
public static LinkedList list=new LinkedList(); 3:gk:j#
/** Creates a new instance of CountCache */ 5Zov<+kE
public CountCache() {} Px8E~X<@
public static void add(CountBean cb){ BCbW;w8aI
if(cb!=null){ /[s$A?
list.add(cb); ra&C|"~E
} %F~
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} ~IXfID!8
} jt3SA
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CountControl.java V6k9L*VP
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/* c>g%oE
* CountThread.java B]vj1m`9
* 6PH*]#PfoD
* Created on 2007年1月1日, 下午4:57 )N/KQ[W
* j7d;1 zB+G
* To change this template, choose Tools | Options and locate the template under PjHm#a3zg%
* the Source Creation and Management node. Right-click the template and choose e#('`vGB
* Open. You can then make changes to the template in the Source Editor. Ua]zTMI
*/ ;p9D2&
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package com.tot.count; -O5m@rwt<
import tot.db.DBUtils; ^kq! /c3r
import java.sql.*; R4/@dA0
/** Ir'f((8:
* FuKNH~MevQ
* @author a|NU)mgEI
*/ J\V(MN,
public class CountControl{ [OcD#~drO
private static long lastExecuteTime=0;//上次更新时间 hG^23FiN
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ,zFN3NLtA
/** Creates a new instance of CountThread */ xpM~*Gpm
public CountControl() {} )N<!3yOz
public synchronized void executeUpdate(){ >U)O@W)
Connection conn=null; if'4MDl
PreparedStatement ps=null; H/$q]i*#K
try{ *v+ fkg
conn = DBUtils.getConnection(); zYL^e @
conn.setAutoCommit(false); +[ zo2lBx
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ^Ram8fW
for(int i=0;i<CountCache.list.size();i++){ w(D9'
CountBean cb=(CountBean)CountCache.list.getFirst(); hd~rC*I
CountCache.list.removeFirst(); rx/6x(3
ps.setInt(1, cb.getCountId()); ;qMlGXW*q
ps.executeUpdate();⑴ 9m6j?CFG}
//ps.addBatch();⑵ @-}]~|<
} brWt
//int [] counts = ps.executeBatch();⑶ Ei-OuDM;)
conn.commit(); (XJQ$n
}catch(Exception e){ u W T[6R
e.printStackTrace(); ~}w 8UO
} finally{ H~Cfni;
try{ WQx;tX
if(ps!=null) { KfNXX>'
ps.clearParameters(); jH1~Ve+q9
ps.close(); wNZ7(W.U
ps=null; i"xDQ$0G6
} %a `dOEO
}catch(SQLException e){} k:Q<Uanc[
DBUtils.closeConnection(conn); 3:Wr)>l}#
} gwJu&HA/
} I>aa'em
public long getLast(){ w C"%b#(}
return lastExecuteTime; S41>VbtEp
} CCO g1X_
public void run(){ SO/]d70HG
long now = System.currentTimeMillis(); pZxL?N!
if ((now - lastExecuteTime) > executeSep) { ; \+0H$
//System.out.print("lastExecuteTime:"+lastExecuteTime); D,a%Je-r,
//System.out.print(" now:"+now+"\n"); IJ;*N
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); =Qrz|$_rv
lastExecuteTime=now; OB22P%
executeUpdate(); cmI#R1\
} ub5hX{uT
else{ Hea<!zPH
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); Y=Qf!Cq]
} W<"\hQI
} =L%3q <]p
} Kf#!IY][
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 5eA]7$ic
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类写好了,下面是在JSP中如下调用。 9DX3]Z\7X
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<% "'Uk0>d=_I
CountBean cb=new CountBean(); B:cOcd?p
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); fx:KH:q3
CountCache.add(cb); (N4(r<o;
out.print(CountCache.list.size()+"<br>"); 'OCo1|iK~
CountControl c=new CountControl(); ->=++
c.run(); J-F_XKqH
out.print(CountCache.list.size()+"<br>"); kB#vh
%>