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: -i8KJzPL f
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CountBean.java S=k!8]/d|
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/* +fk*c[FG
* CountData.java 7z$Z=cs
* 2{h2]F
* Created on 2007年1月1日, 下午4:44 8b?nr;@
* x/O;8^b
* To change this template, choose Tools | Options and locate the template under SxYz)aF~
* the Source Creation and Management node. Right-click the template and choose i]c{(gd`
* Open. You can then make changes to the template in the Source Editor. W p)!G
*/ 'oIE:#b
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package com.tot.count; bX$z)]KKu
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/** {c*$i^T
* )P(S:x'b0
* @author v8-My1toV
*/
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public class CountBean { uU 7 <8G
private String countType; XN<!.RCw
int countId; Z^V;B _
/** Creates a new instance of CountData */ h*VDd3[#
public CountBean() {} j~N*T XkC
public void setCountType(String countTypes){ H=BI%Z
this.countType=countTypes; s^zlBvr|.
} IMWt!#vuY
public void setCountId(int countIds){ fo,0NxF9
this.countId=countIds; Ixn|BCi60A
} ytY\&m
public String getCountType(){ #1%@R<`
return countType; X]y8-}Qf
} 5}G_2<G
public int getCountId(){ STnM Bz7
return countId; aE'nW_f
} 6>)fNCe`
} +DRt2a#
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CountCache.java 7"Xy8]i{z
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/* 6vK`J"d{~D
* CountCache.java d7kE}{,
* /
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* Created on 2007年1月1日, 下午5:01 ~3bV~H#~m
* {Z/iYHv~#c
* To change this template, choose Tools | Options and locate the template under Xgx/ubca0
* the Source Creation and Management node. Right-click the template and choose 1e[?}q]*
* Open. You can then make changes to the template in the Source Editor. x~5,v5R^]
*/ qA '^b~
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package com.tot.count; p-"C^=l
import java.util.*; +1wEoU.l2
/** 0cG[<\qT
* +~V_^-JG&
* @author ]izHn; +
*/ )r.Wge
public class CountCache { m^oG9&";
public static LinkedList list=new LinkedList(); LhAN( [
/** Creates a new instance of CountCache */ K ar!
public CountCache() {} p1'q{E+o*
public static void add(CountBean cb){ vT#R>0@mi
if(cb!=null){ q%G[tXw
list.add(cb); B5 /8LEWw
} C+/EPPi
} Y!j/,FU
} ^!B]V>L-
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CountControl.java V<WWtu;3
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/* C1{Q 4(K%
* CountThread.java "S#$:92
* [,Ul
* Created on 2007年1月1日, 下午4:57 \Yj_U'2"i
* <p<6!tdO
* To change this template, choose Tools | Options and locate the template under
#om Gj&
* the Source Creation and Management node. Right-click the template and choose M%:\ ry4:
* Open. You can then make changes to the template in the Source Editor. yreH/$Ou8
*/ |\Gkhi>;
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package com.tot.count; \'=svJ
import tot.db.DBUtils; P6%qNR/ x
import java.sql.*; $|7"9W}m*
/** C)m@/w
* r4u,I<ZbH
* @author ]A[}:E 5}
*/ b6S"&hs
public class CountControl{ ozsd6&z5l
private static long lastExecuteTime=0;//上次更新时间 r } Wdj
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 cl`kd)"v
/** Creates a new instance of CountThread */ /mJb$5=1
public CountControl() {} r2f%E:-0G
public synchronized void executeUpdate(){ \#biwX
Connection conn=null; 8cfsl lI
PreparedStatement ps=null; n=b!c@f4
try{ $~q{MX&J
conn = DBUtils.getConnection(); 6DHZ,gWq
conn.setAutoCommit(false); 1g=T"O&=
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); }{:Jj/d
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for(int i=0;i<CountCache.list.size();i++){ q>%.zc[x
CountBean cb=(CountBean)CountCache.list.getFirst(); rui 8x4c
CountCache.list.removeFirst(); BT(eU*m-
ps.setInt(1, cb.getCountId()); ,r3`u2)
ps.executeUpdate();⑴ EQoK\.;
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//ps.addBatch();⑵ I.t)sf,
} DBy%"/c
//int [] counts = ps.executeBatch();⑶ ,MHK|8!
conn.commit(); 1WaQWZ:=
}catch(Exception e){ dgQ<>+9]6
e.printStackTrace(); @RB^m(> 5
} finally{ !gyW15z'
try{ '~yxu$aK
if(ps!=null) { z*VK{O)o
ps.clearParameters(); 6GAEQ]
ps.close(); Y, Lpv|
ps=null; 0XljFQ
} .`KzA]
}catch(SQLException e){} \|vo@E
DBUtils.closeConnection(conn); p}~Sgi
} V,zFHXO
} ~9YEb
public long getLast(){ ?pQ0*
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return lastExecuteTime; 'ym Mu}q
} DQ$m@_/4w
public void run(){ l^tRy_T:-
long now = System.currentTimeMillis(); Z[!kEW
if ((now - lastExecuteTime) > executeSep) { i%i s<'
//System.out.print("lastExecuteTime:"+lastExecuteTime); B{`K?e0
//System.out.print(" now:"+now+"\n"); ?!"pzDg
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); "8)%XSb
lastExecuteTime=now; _TdH6[9
executeUpdate(); v"Bm4+c&0
} gr!!pp;
else{ uu-M7>+
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 0WZd $
} ^[I>#U
} (3K,f4S@
} /^K-tz-R
//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 \0i0#Dt9
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类写好了,下面是在JSP中如下调用。 "\lOOp^-
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<% 6[FXgCb
CountBean cb=new CountBean(); <D& Ep
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); V~8]ag4
CountCache.add(cb); lRS'M,/
out.print(CountCache.list.size()+"<br>"); )~xH!%4F
CountControl c=new CountControl(); lV./K;\T
c.run(); x*j
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out.print(CountCache.list.size()+"<br>"); c8zok `\P_
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