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: ,{C
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CountBean.java C0gY
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/* c5em*qCw$
* CountData.java |Vo{ {)
* VPr`[XPXb
* Created on 2007年1月1日, 下午4:44 11iV{ h
* elGwS\sw
* To change this template, choose Tools | Options and locate the template under -=WQed}
* the Source Creation and Management node. Right-click the template and choose >bFrJz}
* Open. You can then make changes to the template in the Source Editor. kXroFLrY
*/ L$z(&%Nx
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package com.tot.count; h(K}N5`
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/** B#;6z%WK
* q o6~)Aws
* @author &_$0lIDQ
*/ r_hs_n!6
public class CountBean { ";U#aK1p
private String countType; o-
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int countId; ]~:WGo=_
/** Creates a new instance of CountData */ a@S{A5j
public CountBean() {} Kw7uUJR
public void setCountType(String countTypes){ 0N87G}Xu
this.countType=countTypes; mUNAA[0 L
} 9RPZj>ezjA
public void setCountId(int countIds){ ;(-Wc9=
this.countId=countIds; Ge`PVwn
} c6T[2Ig
public String getCountType(){ LzQOzl@z
return countType; 5AK@e|G$w
} o1Krp '*
public int getCountId(){ ~l8w]R3A
return countId; JT! Cb$!
} }X/>WiGh:
} Ye| (5f
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CountCache.java \iRmGvT
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/* j#jwK(:]
* CountCache.java 7?;ZE:
* /K(l[M
* Created on 2007年1月1日, 下午5:01 M`&78j
* ;4QE.&s`
* To change this template, choose Tools | Options and locate the template under Urz9S3#\
* the Source Creation and Management node. Right-click the template and choose < V*/1{
* Open. You can then make changes to the template in the Source Editor. Y?6}r;<
*/ ^;sE)L6
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package com.tot.count; -W{ !`<8D
import java.util.*; 6j Rewj
/** ?PYZW5
* 5\Rg%Ezl
* @author 7~~suQ{F4
*/ }X6w"
public class CountCache { ]$BC f4:
public static LinkedList list=new LinkedList(); :*ZijN*{)$
/** Creates a new instance of CountCache */ VHi'~B#'*
public CountCache() {} <@$+uZt+
public static void add(CountBean cb){ S.Q:O{]
if(cb!=null){ Q?bCQZ{-Lh
list.add(cb); . H}R}^
} 1QPz|3f@\
} =$y;0]7Lwi
} H)h$@14xu
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CountControl.java 1k]L ,CX
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/* h[;DRD!Z
* CountThread.java )KY4BBc
* M.\XG}RR
* Created on 2007年1月1日, 下午4:57 Y!`pF
* AyNpY_B0c
* To change this template, choose Tools | Options and locate the template under v|KGzQx$.*
* the Source Creation and Management node. Right-click the template and choose nvCp-Z$
* Open. You can then make changes to the template in the Source Editor. EiDnUL(W7h
*/ 'jXJ!GFw
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package com.tot.count; `An p;el
import tot.db.DBUtils; !+z&] S3s
import java.sql.*; D~FIv
/** "=ki_1/P
* QUm[7<"
* @author jNI9 .45y
*/ w9StW94p
public class CountControl{ aCJ-T8?'
private static long lastExecuteTime=0;//上次更新时间 dlA0&;}z
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 Xf{9rZ+
/** Creates a new instance of CountThread */ OnH3Ss$
public CountControl() {} )gD2wk(
public synchronized void executeUpdate(){ 53$;ZO3
Connection conn=null; iaJLIr l
PreparedStatement ps=null; H&
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try{ 6HPuCP
conn = DBUtils.getConnection(); LLFQ5py{
conn.setAutoCommit(false); l_4^TYF
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); Cd]g+R}j
for(int i=0;i<CountCache.list.size();i++){ :*/g~y(fE
CountBean cb=(CountBean)CountCache.list.getFirst(); 1>/ iYf
CountCache.list.removeFirst(); Qp7F3,/#
ps.setInt(1, cb.getCountId());
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ps.executeUpdate();⑴ <(_Tanx9Q
//ps.addBatch();⑵ {6O}E9
} l$kO%E'
//int [] counts = ps.executeBatch();⑶ |N}*
conn.commit(); ;Ea8>
}catch(Exception e){ dq%C~j{v
e.printStackTrace(); })`z6d]3
} finally{ )w5!'W4Z8
try{ i8KoJY"
if(ps!=null) { -GMaK.4=
ps.clearParameters(); mHAfK B
ps.close(); DZ1.Bm0
ps=null; Y78DYbU.
} As5-@l`@
}catch(SQLException e){} E#3tkFF0Z[
DBUtils.closeConnection(conn); 3}8L!2_p
} $E!f@L
} LqO=wK~
public long getLast(){ c^cr_i
return lastExecuteTime; `Z#':0Z
} c[V.j+Iy#^
public void run(){ h:|BQC
long now = System.currentTimeMillis(); K2\)9
if ((now - lastExecuteTime) > executeSep) { cq 5^7.
//System.out.print("lastExecuteTime:"+lastExecuteTime); yJ`{\7Uqg
//System.out.print(" now:"+now+"\n"); $=ESY>MO
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ^O=G%de
lastExecuteTime=now; cs_
executeUpdate(); M6 8foeeN
} 7<=p*
else{ L7n G5i
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); (>Nwd^
} E!.&y4
} db=S*LUbl
} , Y,^vzX6
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 IlwHHt;njp
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类写好了,下面是在JSP中如下调用。 W'=}2Y$]u
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<% *wsZ aQ
CountBean cb=new CountBean(); ~g%Ht#<
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); l^KCsea#
CountCache.add(cb); BJ\81 R
out.print(CountCache.list.size()+"<br>"); WMW=RgiW\
CountControl c=new CountControl(); \rATmjsKzS
c.run(); Vr d16s
out.print(CountCache.list.size()+"<br>"); sP}u zS
%>