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: `8FC&%X_
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CountBean.java iZMsN*9[
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/* Sa,N1r
* CountData.java 'EZ[aY!);
* V2 VsJ
* Created on 2007年1月1日, 下午4:44 m9G,%]4|
* o95O!5 hl
* To change this template, choose Tools | Options and locate the template under e!4akKw4wD
* the Source Creation and Management node. Right-click the template and choose a+{g~/z;,Q
* Open. You can then make changes to the template in the Source Editor. ,xD{A}}V
*/ jLQjv
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package com.tot.count; 1
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/** (X>y)V
* SOK2{xCG
* @author CCEx>*E6c
*/ w|L~+
public class CountBean { =R>Sxaq
private String countType; pK'WJ
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int countId; 3~cOQ%#]4
/** Creates a new instance of CountData */ A^K,[8VX
public CountBean() {} M%B[>pONb7
public void setCountType(String countTypes){ l m
this.countType=countTypes; e-e{-pB6
} 5)nv
public void setCountId(int countIds){ }qKeX4\-
this.countId=countIds; >`{i[60r
} BB%(!O4Dl
public String getCountType(){ (Wx)YI
return countType; Ap!UX=HBb
} 0H>Fyl2_
public int getCountId(){ 7_K(xmK
return countId; tjd"05"@:
} vj^UF(X
} ZH0f32K
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CountCache.java N"T8
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/* O]Kb~jkd
* CountCache.java }TF<C!]
* 6U&Uyd)
* Created on 2007年1月1日, 下午5:01 z!3Z^d`
* rmabm\QY
* To change this template, choose Tools | Options and locate the template under %'=oMbi>i4
* the Source Creation and Management node. Right-click the template and choose Qy70/on9
* Open. You can then make changes to the template in the Source Editor. VuPET
*/ dt \O7Rjw8
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package com.tot.count; i3%~Gc63
import java.util.*; ~qqtFjlG^
/** q~w;C([k_
* xlwsZm{V
* @author 'I<j`)4`d
*/ L3GJq{t
public class CountCache { 'D/AL\1{p(
public static LinkedList list=new LinkedList(); +.N;h-'
/** Creates a new instance of CountCache */ 4z*_,@OA
public CountCache() {} @ [FFYVru
public static void add(CountBean cb){ UpIf t=@P
if(cb!=null){ u}:O[DG
list.add(cb); XBY"7}
} h7y*2:l6
} YSwD#jO0
} =#^dG''*"
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CountControl.java 0iL8i#y*
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/* )F$Stg3e
* CountThread.java 41zeN++
* ZbrE m
* Created on 2007年1月1日, 下午4:57 j |i6/Pk9J
* R/wSGP`W
* To change this template, choose Tools | Options and locate the template under s{,e^T
* the Source Creation and Management node. Right-click the template and choose /,>.${,;u
* Open. You can then make changes to the template in the Source Editor. X<QE]RZ
*/ J6%op{7/
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package com.tot.count; Orb(xLChJ
import tot.db.DBUtils; kp6x6%{K\
import java.sql.*; K$]QzPXS
/** zh.c_>jS
* lET)<V(Y
* @author P
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*/ }dHiW:J>
public class CountControl{ u#,]>;
private static long lastExecuteTime=0;//上次更新时间 O.E0LCABC
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 :I$2[K
/** Creates a new instance of CountThread */ {S}@P~H=
public CountControl() {} Y o(B8}?0!
public synchronized void executeUpdate(){ Sy'>JHx
Connection conn=null; dJ!o/y6
PreparedStatement ps=null; -Fdi,\e
try{ 3?XLHMxW
conn = DBUtils.getConnection(); e||_j
conn.setAutoCommit(false); %OtW\T=u
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); =z/F=1^<
for(int i=0;i<CountCache.list.size();i++){ D1n2Z:9
CountBean cb=(CountBean)CountCache.list.getFirst(); 2|=_kN8;
CountCache.list.removeFirst(); kwL)&@
ps.setInt(1, cb.getCountId()); Ih7Eq/iu
ps.executeUpdate();⑴ ry\']\k
//ps.addBatch();⑵ o{he)r6)_
} q"Md)?5N
//int [] counts = ps.executeBatch();⑶ #Kl2K4
conn.commit(); +o3g]0
}catch(Exception e){ z3C^L
e.printStackTrace(); ul?BKV+3E
} finally{ qLP+@wbJ
try{ =c,gK8C
if(ps!=null) { X]fw9tZ
ps.clearParameters(); V~_nyjrJM
ps.close(); PsgzDhRv
ps=null; K;qZc\q
} TUaK:*x*
}catch(SQLException e){} [:QMnJ
DBUtils.closeConnection(conn); (*RybKoaA
} zvf]}mNx
} ;Wa{q.)
public long getLast(){ &~%@QC/
return lastExecuteTime; N>R%0m<e
} ie(7m|.
public void run(){ (<l2 ^H
long now = System.currentTimeMillis(); v'!Ntk
if ((now - lastExecuteTime) > executeSep) { 3+-(;>>\
//System.out.print("lastExecuteTime:"+lastExecuteTime); Q]wM/7
//System.out.print(" now:"+now+"\n"); wuzz%9;@B
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); XNUqZ-M:
lastExecuteTime=now; [&CM-`
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executeUpdate(); a~*V
} ^kr)U8
else{ W/>?1+r.Z
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); iy]}1((hR
} $3TTHS o
} i .N1Cvp&
} !_9$[Oq~
//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 h)rf6*hw
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类写好了,下面是在JSP中如下调用。 UTQKlwPa
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<% k&/)g3(N(
CountBean cb=new CountBean(); IDh`0/i]
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); Xa@wN/"F
CountCache.add(cb); (UF!Zb]{
out.print(CountCache.list.size()+"<br>"); Gme$FWa
CountControl c=new CountControl(); DANSexW
c.run(); !XG&=Rd?
out.print(CountCache.list.size()+"<br>"); EKPTDKut
%>