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: TUIj-HSe
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CountBean.java jA$g0>
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/* QzPq^
* CountData.java U[*VNJSp
* F^7qLvh
* Created on 2007年1月1日, 下午4:44 K~H)XJFF
* K:Wxx"
* To change this template, choose Tools | Options and locate the template under i6?,2\K
* the Source Creation and Management node. Right-click the template and choose %%`Nq&'
* Open. You can then make changes to the template in the Source Editor. #:s*)(Qn
*/ P,k~! F^L
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package com.tot.count; kQ7$,K#
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/** 0^az<!!O#
* :tp2@*]9Z
* @author =@AWw:!:,
*/ V&;1n
public class CountBean { J 05@SG':
private String countType; Yz=(zj
int countId; OXe+=Lp<
/** Creates a new instance of CountData */ [9(tIb!x
public CountBean() {} t.$3?"60~
public void setCountType(String countTypes){
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this.countType=countTypes; CnSf GsE>
} hEi]-N\X
public void setCountId(int countIds){ 'iA#lKG
this.countId=countIds; GwQW
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} SeN4gr*
public String getCountType(){ $,v
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return countType; Zk4Hs%n
} GR@!mf
public int getCountId(){ +~?ze,Di
return countId; N+ZDQa[
} )uC],CbW{
} T6h-E^Z
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CountCache.java id<i|
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/* )Fx"S.Ok
* CountCache.java 11[[H kX@
* reR ><p
* Created on 2007年1月1日, 下午5:01 C,~wmS )@
* 1j0OV9 -|
* To change this template, choose Tools | Options and locate the template under \ZX5dFu0
* the Source Creation and Management node. Right-click the template and choose T]-yTsto
* Open. You can then make changes to the template in the Source Editor. eQu%TZ(x-$
*/ <f.* =/]W2
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package com.tot.count; Zu`;
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import java.util.*; h6<abT@I
/** ~T@t7Cg
* BZejqDr*
* @author x|U~?
*/ F-[zuYGp
public class CountCache { 7[h_"@_A7
public static LinkedList list=new LinkedList(); XK??5'&{
/** Creates a new instance of CountCache */ IROX]f}r (
public CountCache() {} 4)0 %^\p
public static void add(CountBean cb){ QEKSbxL\W
if(cb!=null){ i!+D
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list.add(cb); BLZ#vJR
} 6r!
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} 4
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} TP o%zZo
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CountControl.java qX{"R.d
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/* wgfA\7Z
* CountThread.java .] mYpz
* 9qN4f8R
* Created on 2007年1月1日, 下午4:57 oJa6)+b(3
* YL-/z4g
* To change this template, choose Tools | Options and locate the template under Z?X0:WK
* the Source Creation and Management node. Right-click the template and choose Mx{VN
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* Open. You can then make changes to the template in the Source Editor. o|Cq#JFG
*/ OzY55
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package com.tot.count; #[0:5$-[
import tot.db.DBUtils; t\~lGG-p
import java.sql.*; ddvSi6
/** pYZ6-s
* QR4rQu
* @author &7z79#1NS
*/ U<,@u,_Ja
public class CountControl{ 2gz}]_
private static long lastExecuteTime=0;//上次更新时间 kms&o=^
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 z@;]Hy
/** Creates a new instance of CountThread */ W%LTcm
public CountControl() {} ?&;d#z*4
public synchronized void executeUpdate(){ KilgeN:
Connection conn=null; CvfXm
PreparedStatement ps=null; zvjVM"=G
try{ X8~dFjhX
conn = DBUtils.getConnection(); *uHL'Pe;m
conn.setAutoCommit(false); uo0g51%9
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ,:g.B\'Q
for(int i=0;i<CountCache.list.size();i++){ $$ %4,\{l
CountBean cb=(CountBean)CountCache.list.getFirst(); y_O [r1MF
CountCache.list.removeFirst(); 5tPBTS<<"L
ps.setInt(1, cb.getCountId()); K$OxeJP?F
ps.executeUpdate();⑴ -c-af%xD
//ps.addBatch();⑵ =|>CB
} hY
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//int [] counts = ps.executeBatch();⑶ [-o`^;
conn.commit(); Gr9/@U+
}catch(Exception e){ vSty.:bY\p
e.printStackTrace(); Fe
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} finally{ }L
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try{ /2}o:vLj
if(ps!=null) { Q#C;4)e
ps.clearParameters(); ?#8',:
ps.close(); r~cmrLQa
ps=null; H`u8}{7
} ZeewGa^r
}catch(SQLException e){} $YZsaw
DBUtils.closeConnection(conn); lv
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} 1d/-SxhZ
} 0dS}pd">k
public long getLast(){ .5Y%I;~v
return lastExecuteTime; EvZ;i^.8LS
} *hVbjI$
public void run(){ GC?X>AC:
long now = System.currentTimeMillis(); |GuIp8~
if ((now - lastExecuteTime) > executeSep) { RmS|X"zc
//System.out.print("lastExecuteTime:"+lastExecuteTime); D|-^}I4
//System.out.print(" now:"+now+"\n"); x._IP,vRx^
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); sYV7t*l
lastExecuteTime=now; fw>@:m_bK
executeUpdate(); !iKR~&UpAL
} DxjD/?R8
else{ JQ{g'cT
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); m87,N~DP
} k=w;jX&;`
} .K?',x
} TU ]Ed*'&
//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 m"Y;GzqQl
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类写好了,下面是在JSP中如下调用。 &`>[4D*
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<% z;1y7W!v
CountBean cb=new CountBean(); =Y`P}vI]w%
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); |8I #`
CountCache.add(cb); 8r
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out.print(CountCache.list.size()+"<br>"); ^NJ]~h{n$
CountControl c=new CountControl(); Zgp]s+%E
c.run(); [6x-c;H_4
out.print(CountCache.list.size()+"<br>"); rkhQoYZ[
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