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: L"'=[O~
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CountBean.java :Vxt2@p{
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/* >2s6Y
* CountData.java :=B.)]F.)
* E.*hY+kGZ
* Created on 2007年1月1日, 下午4:44 J920A^)j!
* 0HWSdf|w
* To change this template, choose Tools | Options and locate the template under K F'fg
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* the Source Creation and Management node. Right-click the template and choose d7kE}{,
* Open. You can then make changes to the template in the Source Editor. /
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*/ ~3bV~H#~m
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package com.tot.count; J6CSu7Voa
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/** XdJD"|,h
* t#.}0Te7
* @author us.[wp'Sh
*/ C[,h!
public class CountBean { ~S('\h)1
private String countType; ^Z)7Z%
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int countId; _9=87u0
/** Creates a new instance of CountData */ `e ZDG
public CountBean() {} ~a_hOKU5
public void setCountType(String countTypes){ 7;p/S#P:
this.countType=countTypes; bR7tmJ[)Z
} cgG*7E
public void setCountId(int countIds){ JAHg_!
this.countId=countIds; U1:m=!S;x
} Yuv=<V
public String getCountType(){ _zDS-e@
return countType; Tp-W/YC
} jP<6J(
public int getCountId(){ 8d*S9p,/
return countId; r#WqXh_uk
} Oey
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} >aJmRA-C}
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CountCache.java !!L'{beF
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/* ky|k g@n{
* CountCache.java ;}6wj@8He
* L&+k`b
* Created on 2007年1月1日, 下午5:01 lai@,_<GV
* eM!Oc$C8[
* To change this template, choose Tools | Options and locate the template under Ly(iq
* the Source Creation and Management node. Right-click the template and choose (^~a1@f,J
* Open. You can then make changes to the template in the Source Editor. 9 5!xJdq
*/ 2`Bb9&ut>
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package com.tot.count; D% *ww'mt0
import java.util.*; gA=Pz[i)p
/** s[7$%|~W
* nrE.0Ue1
* @author b6S"&hs
*/ @8 c@H#H
public class CountCache { iJh{,0))g
public static LinkedList list=new LinkedList(); `}t5` :#k
/** Creates a new instance of CountCache */ "zw{m+7f,
public CountCache() {} ]iTP5~8U
public static void add(CountBean cb){ ;LgMi5dN
if(cb!=null){ T^eD
list.add(cb); ]foS.D,
} ,sj(g/hg
} ?6*\M
} @8\0@[]
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CountControl.java W
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/* al Rz@N
* CountThread.java v "2A?
* ipu~T)}
* Created on 2007年1月1日, 下午4:57 A
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* F+G+XtOS
* To change this template, choose Tools | Options and locate the template under 9/8+R%
* the Source Creation and Management node. Right-click the template and choose -ik$<>{X
* Open. You can then make changes to the template in the Source Editor. nd\$Y
*/ (Qw >P42J
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package com.tot.count; lw8t#_P
import tot.db.DBUtils; M.SF}U
import java.sql.*; 0XljFQ
/** y+^KVEw
* YO.ddy*59
* @author 0{d)f1
*/ maSVq G
public class CountControl{ {y{O ze
private static long lastExecuteTime=0;//上次更新时间 b!-=L&V
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 mb_6f:Qh3
/** Creates a new instance of CountThread */ DIYR8l}x
public CountControl() {} \*5z0A9)5)
public synchronized void executeUpdate(){ S^1ZsD.
Connection conn=null; Z!q$d/1
PreparedStatement ps=null; .,VLQbtg
try{ \1?'JdN
conn = DBUtils.getConnection(); `+."X1
conn.setAutoCommit(false); .5SYN-@
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); @(6P L^I
for(int i=0;i<CountCache.list.size();i++){ _TdH6[9
CountBean cb=(CountBean)CountCache.list.getFirst(); v"Bm4+c&0
CountCache.list.removeFirst(); ~"bBwPI
ps.setInt(1, cb.getCountId()); ?Z!R
ps.executeUpdate();⑴ qz)KCEs
//ps.addBatch();⑵ "KCG']DF
} I=Y_EjZD
//int [] counts = ps.executeBatch();⑶ C5KUIOg
conn.commit(); k g(}%Ih
}catch(Exception e){ kxrYA|x
e.printStackTrace(); SPe%9J+
} finally{ %Ze7d&
try{ A]%*ye"NT
if(ps!=null) { PXl%"O%d
ps.clearParameters(); 1D1kjM^Bo
ps.close(); ?]*"S{Cq v
ps=null; lt'N{LFvc
} )C\/ (
}catch(SQLException e){} )`<&~>qp
DBUtils.closeConnection(conn); `p)U6J
} butBS
} -oZw+ge}
public long getLast(){ T#e|{ZCbq
return lastExecuteTime; 4K~>
} am'K$s
public void run(){ W3('1
long now = System.currentTimeMillis(); L;Yn q<x
if ((now - lastExecuteTime) > executeSep) { 6 %` h2Z
//System.out.print("lastExecuteTime:"+lastExecuteTime); 1TzwXX7
//System.out.print(" now:"+now+"\n"); CG35\b;Q
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ;xFB
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lastExecuteTime=now; /A>nsN?:]
executeUpdate(); 6c>:h)?
} <RbsQ^U
else{ 4"nYxL"<4
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); .|P
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} Gf!c
} 2#qcYU
} CCC9I8rZD
//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 1JOoICjB
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类写好了,下面是在JSP中如下调用。 j:8Pcx
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<% 5|}u25J
CountBean cb=new CountBean(); WK0IagYw
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); @tRDKPh
CountCache.add(cb); 3C;;z
out.print(CountCache.list.size()+"<br>"); 5)rN#_BKj
CountControl c=new CountControl(); :Ez*<;pF'
c.run(); -`X`Ff
out.print(CountCache.list.size()+"<br>"); V<}chLd,
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