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: mBEMwJ}O`
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CountBean.java U'^ G-@
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/* Ng1bjq}E2
* CountData.java ?\I@w4
* 6"[J[7up
* Created on 2007年1月1日, 下午4:44 g[' 7 $
* La28%10
* To change this template, choose Tools | Options and locate the template under ly69:TR7I
* the Source Creation and Management node. Right-click the template and choose 'pyIMB?x
* Open. You can then make changes to the template in the Source Editor. od$$g(
*/ F >H\F@Wl
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package com.tot.count; DQ}&J
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/**
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* M+M ;@3
* @author uGn BlR$}
*/ Adet5m.|[8
public class CountBean { JC`;hY
private String countType; 2I3H?Lrx!m
int countId; s1R#X~d
/** Creates a new instance of CountData */ 39m8iI%w[
public CountBean() {} vTo+jQs^
public void setCountType(String countTypes){ vT MCZ+^g
this.countType=countTypes; OLWn0
} S(Z\h_m(
public void setCountId(int countIds){ :fDzMD
this.countId=countIds; q6hH]Q>w*
} 0}YadNb7
public String getCountType(){ +U<.MVOo.
return countType; belBdxa{"
} LN)yQ-
public int getCountId(){ L8Q/!+K
return countId; c_,pd
} \Unawv~
} Xgl
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CountCache.java +vH#xc\'
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/* &> _aY #
* CountCache.java j+>[~c;0)
* -tx%#(?wH
* Created on 2007年1月1日, 下午5:01 [VLq/lg*
* I %sw(uoE
* To change this template, choose Tools | Options and locate the template under "$b{EYq6
* the Source Creation and Management node. Right-click the template and choose q,_EHPc
* Open. You can then make changes to the template in the Source Editor. N?8nlrDQ
*/ Q-A_ 8
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package com.tot.count; R5mb4
import java.util.*; V6+:g=@U-l
/** 4jlwu0L+
* YzJWS|]
* @author p.<d+S<
*/ :?}>Q
public class CountCache { `9k\~D=D~
public static LinkedList list=new LinkedList(); ,$aqF<+;
/** Creates a new instance of CountCache */ T24$lhM
public CountCache() {} 1NG[
public static void add(CountBean cb){ FI[]#
if(cb!=null){ eL'fJcjw<
list.add(cb); Dw 5Ze
} fOKAy'
} =*.S<Ko)
} z
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CountControl.java Q<DXDvL
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/* g~(G P
* CountThread.java asE.!g?
* e|>@ >F]K
* Created on 2007年1月1日, 下午4:57 QxuU3#l
* \F\xZ.r
* To change this template, choose Tools | Options and locate the template under RH$l?j6
* the Source Creation and Management node. Right-click the template and choose R&:Qy7"
* Open. You can then make changes to the template in the Source Editor. &|h9L' mr
*/ z_#HJ}R=
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package com.tot.count; /1m+iM^V
import tot.db.DBUtils; il"pKQF
import java.sql.*;
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/** |Bv,*7i&
* <[T{q
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* @author $VP\Ac,!
*/ I)9,
public class CountControl{ VV#'d
private static long lastExecuteTime=0;//上次更新时间 a1ps'^Qhh
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 6OJhF7\0&
/** Creates a new instance of CountThread */ Jh36NE8r
public CountControl() {} 0W_u"UY$c
public synchronized void executeUpdate(){ ,1.Td=lY$
Connection conn=null; w_;$ahsu~
PreparedStatement ps=null; ~$rSy|19
try{ mVN\
conn = DBUtils.getConnection(); (dy:d^
conn.setAutoCommit(false); _PQk<QZ
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); <]_[o:nOP
for(int i=0;i<CountCache.list.size();i++){ 5 /T#>l<
CountBean cb=(CountBean)CountCache.list.getFirst(); hZ/p'
CountCache.list.removeFirst(); 7AqbfLO
ps.setInt(1, cb.getCountId()); '|*e4n
ps.executeUpdate();⑴ C[l5[DpH
//ps.addBatch();⑵ J l{My^I5
} bA'N2~.,
//int [] counts = ps.executeBatch();⑶ hSN38wy
conn.commit(); U-$nwji
}catch(Exception e){ #;+SAoN
e.printStackTrace(); !w0=&/Y{R
} finally{ U7e2NES
try{ *y` (^kyS
if(ps!=null) { kw7E<aF!
ps.clearParameters(); 6\v4#
ps.close(); rJB/)4
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ps=null; q0['!G%["
} PsS.lhj0"
}catch(SQLException e){} b2j~"9
DBUtils.closeConnection(conn); (^_INy*
} [r9HYju=
} : w>R|]
public long getLast(){ R((KAl]dL
return lastExecuteTime; i=hA. y`
} -6X+:r`>u
public void run(){ zz<o4bR
long now = System.currentTimeMillis(); T-x9IoE
if ((now - lastExecuteTime) > executeSep) { " ub0}p4V
//System.out.print("lastExecuteTime:"+lastExecuteTime); r^ '
//System.out.print(" now:"+now+"\n"); RMid}BRE
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); [M:<!QXw
lastExecuteTime=now; ytV[x
executeUpdate(); Bt1v7M
} 79k+R9m
else{ ,w=u?
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 6\VZ6oS
} eOfVBF<C2
} J$T(p%
} JL<<EPC
//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 F7]8*[u
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类写好了,下面是在JSP中如下调用。 o h9L2 "
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<% H
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CountBean cb=new CountBean(); l&mY}k
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); v0bP|h[t
CountCache.add(cb); ~E vGNnTL
out.print(CountCache.list.size()+"<br>"); 9Sa6v?sRor
CountControl c=new CountControl(); xK5~9StP
c.run(); 7xO~v23oe
out.print(CountCache.list.size()+"<br>"); )YZx]6\l)
%>