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: t.485L%
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CountBean.java FzFY2h;n]B
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/* v=iz*2+X
* CountData.java w9H%u0V?
* |P>>
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* Created on 2007年1月1日, 下午4:44 ib;:*
* YmNBtGhT
* To change this template, choose Tools | Options and locate the template under u
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* the Source Creation and Management node. Right-click the template and choose @;JT }R H-
* Open. You can then make changes to the template in the Source Editor. !N?|[n1
*/ `b# w3 2
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package com.tot.count; Zb<DgJ=3
hdfNXZ{A"
/** D@7\Fg
* yrE|cH'f0
* @author )I$_wB!UV
*/ 52{jq18&
public class CountBean { CYes'lr
private String countType; OB;AgE@
int countId; LtXFGPQ f
/** Creates a new instance of CountData */ V~NS<!+q
public CountBean() {} D9 ,~Fc
public void setCountType(String countTypes){ d=Q0/sI&
this.countType=countTypes; L`yS'
} - "h
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public void setCountId(int countIds){ q}1AV7$Ai
this.countId=countIds; i*nNu-g
} q@r8V&-<
public String getCountType(){ m:ITyQ+
return countType; E.}T.St
} 6*tI~
public int getCountId(){ \62|w HX
return countId; "72
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} ^#vWdOlt
} C(xdiQJh
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CountCache.java rP^2MH"
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/* vb\ UP&Ip
* CountCache.java [gqV}Y"Md
* oju4.1
* Created on 2007年1月1日, 下午5:01 P0 hC4Sxf
* GyRU/0'BME
* To change this template, choose Tools | Options and locate the template under "qMd%RP
* the Source Creation and Management node. Right-click the template and choose Y GvtG U-
* Open. You can then make changes to the template in the Source Editor. }+,1G!?z
*/ *=UEx0_!q
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package com.tot.count; s-3vp
import java.util.*; ,K,n{3]
/** !1-:1Whz8
* QE m6#y
* @author Z_ak4C
*/ #e{l:!uS\
public class CountCache { bCy.S.`jHQ
public static LinkedList list=new LinkedList(); o3qBRT0[R
/** Creates a new instance of CountCache */ M,3sK!`>
public CountCache() {} vqJiMa j@Z
public static void add(CountBean cb){ G#
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if(cb!=null){ m80Q Mosp
list.add(cb); eM*@}3
} b:+.Y$%F-
} O{%yO=`r
} o~*% g.
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CountControl.java rB<
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/* |z-A;uL <
* CountThread.java v0apEjT
* &3:-(:<U
* Created on 2007年1月1日, 下午4:57 '>@evrG
* roVGS{4T\
* To change this template, choose Tools | Options and locate the template under B24wn8<
* the Source Creation and Management node. Right-click the template and choose |36d<b Io
* Open. You can then make changes to the template in the Source Editor. >E^sZmY[f-
*/ _r?H by<b
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package com.tot.count; ApG_Gd.
import tot.db.DBUtils; PI)lJ\
import java.sql.*; .Q>.|mu
/** 8I$>e (
* */u_RJ
* @author ]wc'h>w
*/ zL+jlUkE
public class CountControl{ Gh>Rt=Qu%
private static long lastExecuteTime=0;//上次更新时间 gC>
A*~J;
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 Cz#0Gh>1
/** Creates a new instance of CountThread */ xKv\z1ra
public CountControl() {} -V%"i,t
public synchronized void executeUpdate(){ 4`7N}$j#,
Connection conn=null; s%1 O}X$c
PreparedStatement ps=null; qm{(.b^
try{ 4703\
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conn = DBUtils.getConnection(); v8I&~_b
conn.setAutoCommit(false); %}J[EV
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); XBh0=E?qiS
for(int i=0;i<CountCache.list.size();i++){ }N&}6U
CountBean cb=(CountBean)CountCache.list.getFirst(); H"=%|/1M0
CountCache.list.removeFirst(); kD8$ir'UYG
ps.setInt(1, cb.getCountId()); .-awl1 W
ps.executeUpdate();⑴ 9i;%(b{
//ps.addBatch();⑵ N>/!e787OU
} %-/[.DYt
//int [] counts = ps.executeBatch();⑶ =e$<["
conn.commit(); 1~zzQ:jAZ
}catch(Exception e){ YNRpIhb
e.printStackTrace(); F w)#[
} finally{ 6c$ so
try{ $BXZFC_1S
if(ps!=null) { qRZv[T%*Q
ps.clearParameters(); !D!~4h)
ps.close(); wqk D
ps=null; ZUyG
}6)J
} V|13%aE_v
}catch(SQLException e){} iP]KV.e'/C
DBUtils.closeConnection(conn); A,Wwt
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} ;6KcX \g-
} J<'[P$D
public long getLast(){ lmi,P-Q
return lastExecuteTime; |-a5|3
} k Pi%RvuQ
public void run(){ U0 nSI
long now = System.currentTimeMillis(); -GCC
if ((now - lastExecuteTime) > executeSep) { MxQhkY-=
//System.out.print("lastExecuteTime:"+lastExecuteTime); Ye% e!
//System.out.print(" now:"+now+"\n"); ePv3M&\J
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); sEkfmB2J/
lastExecuteTime=now; %IL]
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executeUpdate(); aMe]6cWHV>
} ]V0V8fU|
else{ Z$LWZg
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); dWqKt0uh!
} `<2k.aW4e8
} Q3[MzIk 4
} =(2y$,6g?
//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 wI8
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类写好了,下面是在JSP中如下调用。 "\cDSiD
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<% 2[
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CountBean cb=new CountBean(); <:/Lap#D^
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); &W+lwEu
CountCache.add(cb); 6
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out.print(CountCache.list.size()+"<br>"); >Q3_-yY+
CountControl c=new CountControl(); : fMQ,S0
c.run(); DB%}@IW"
out.print(CountCache.list.size()+"<br>"); "jV:L
%>