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: ~DLIz g7p!
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CountBean.java 3z{S}~
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/* (OQ?<'Qa
* CountData.java bO49GEUT _
* 0zqj0
* Created on 2007年1月1日, 下午4:44 PdY>#Cyh
* ^ua12f
* To change this template, choose Tools | Options and locate the template under +zWrLf_Rc
* the Source Creation and Management node. Right-click the template and choose @XOi62(
* Open. You can then make changes to the template in the Source Editor. G+)?^QTn
*/ |Vx~fK S\
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package com.tot.count; z^sST
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/** !v!N>f4S$
* iUr xJh
* @author dDKqq(9(`
*/ 8U.$FMx :
public class CountBean { za,2r^
private String countType; Nm8w/Q5D`
int countId; 0^]t"z5f0
/** Creates a new instance of CountData */ w1B<0'#
public CountBean() {} FsCwF&/q
public void setCountType(String countTypes){ zj]b&In6;
this.countType=countTypes; L(WOet( '
} ccO
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public void setCountId(int countIds){ <<3+g"enno
this.countId=countIds; Ugi5OKdj7)
} RT"O;P
public String getCountType(){ +0pW/4x
return countType; PW_`qP:
} $(>f8)Uku(
public int getCountId(){ PI7IBI
return countId; 6tOi^+qN
} '\*A"8;h
} k)E ;(
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CountCache.java fkW(Dt,
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/* MM_py!=>7
* CountCache.java *d
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* I=YCQ VvA
* Created on 2007年1月1日, 下午5:01 "d?f:x3v^
* 7b.U!Ju
* To change this template, choose Tools | Options and locate the template under `=!p$hg($
* the Source Creation and Management node. Right-click the template and choose J1-):3A
* Open. You can then make changes to the template in the Source Editor. PN\V[#nS
*/ \:sk9k
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package com.tot.count; v+tO$QZ`
import java.util.*; ^\YQ_/\~L
/** ~t9$IB
* P,1exgq9
* @author vug-n 8
*/ ~yN(-I1P
public class CountCache { ChIoR:y>
public static LinkedList list=new LinkedList(); e<'U8|}hc{
/** Creates a new instance of CountCache */ *?Wtj
public CountCache() {} }'jV/
public static void add(CountBean cb){ 5c~'!: 7
if(cb!=null){ Ck(.N
list.add(cb); v,\93mNp[
} SY6r 8RK
} |p'i,.(c_W
} K%<GU1]-]
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CountControl.java /:6Q.onmLn
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/* G4yUC<TqBP
* CountThread.java 5TET<f6R
* &V;x 4
* Created on 2007年1月1日, 下午4:57 ew"m!F#
* B_@7IbB
* To change this template, choose Tools | Options and locate the template under 6ZHv,e`?
* the Source Creation and Management node. Right-click the template and choose NhtEW0xCr
* Open. You can then make changes to the template in the Source Editor. J_/05(48
*/ %EB;1
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package com.tot.count; Q}z{AZ
import tot.db.DBUtils; 0(vdkC4\A
import java.sql.*; 7h1"^}M&
/** I:/4t^%
* -CElk[u
* @author ZW2s[p r
*/ [5LMt*Y
public class CountControl{ aZ/yCS7
private static long lastExecuteTime=0;//上次更新时间 *C/KM;&
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 fSC.+,qk
/** Creates a new instance of CountThread */ `g8tq
public CountControl() {} 3It8&x:
public synchronized void executeUpdate(){ %f#\i#G<k
Connection conn=null; Jh(mbD
PreparedStatement ps=null; 2_Jb9:/X
try{ agTK=
conn = DBUtils.getConnection(); %((cFQ9
conn.setAutoCommit(false); T=yCN#cqQ`
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); i\Q":4
for(int i=0;i<CountCache.list.size();i++){ PE7t_iSV
CountBean cb=(CountBean)CountCache.list.getFirst(); >!G5]?taa
CountCache.list.removeFirst(); E$&;]a
ps.setInt(1, cb.getCountId()); 2E([#Pzb
ps.executeUpdate();⑴ HqDa2q4
//ps.addBatch();⑵ (T2<!&0 @
} dff#{
//int [] counts = ps.executeBatch();⑶ :9O|l)N)W=
conn.commit(); `0[fLEm
}catch(Exception e){ tQ6| PV
e.printStackTrace(); tQCj)Ms 'X
} finally{ Z0z)
try{ L]a|vp
if(ps!=null) { %SFw~%@3&~
ps.clearParameters(); }(rzH}X@
ps.close(); j~Ff/O
ps=null; tpd|y|
} b`?M9f5
}catch(SQLException e){} t3M0La&
DBUtils.closeConnection(conn); KD9Ca $-
} B4 <_"0
} OT"lP(,
public long getLast(){ ~CJYQFt
return lastExecuteTime; cxk=|
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} H;X~<WN&AW
public void run(){ G)K9la<p
long now = System.currentTimeMillis(); !zl/0o
if ((now - lastExecuteTime) > executeSep) { "9.6\Y\*
//System.out.print("lastExecuteTime:"+lastExecuteTime); ~v,!n/('
//System.out.print(" now:"+now+"\n"); hXBqz9
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); Zm5nLxM
lastExecuteTime=now; ]#+5)[N$>
executeUpdate(); ;S{ZC5
} M`q#,Y?3^I
else{ J~:kuf21
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); Dj/Q1KY$m
} )/i4YLO
} X ^9t
} 8F.(]@NY
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 [29$~.m$Y
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类写好了,下面是在JSP中如下调用。 X{4xm,B/
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<% Iy-u`S
CountBean cb=new CountBean(); \y<+Fac1S
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); pq@$&G
CountCache.add(cb); UYlJO{|a
out.print(CountCache.list.size()+"<br>"); ]IL3 $eR
CountControl c=new CountControl(); "P9wT)J_
c.run(); C[^a/P`i
out.print(CountCache.list.size()+"<br>"); )vxVg*.Ee
%>