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: vQ/}E@?u
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CountBean.java :xJ]#
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/* oNQ;9&Z,^2
* CountData.java wgfA\7Z
* .] mYpz
* Created on 2007年1月1日, 下午4:44 9qN4f8R
* ~,+n_KST;
* To change this template, choose Tools | Options and locate the template under j[l6&eX
* the Source Creation and Management node. Right-click the template and choose xFxl9oM."
* Open. You can then make changes to the template in the Source Editor. WA}<Zme3[
*/ _J(n~"eR
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package com.tot.count; /WlK*8C
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/** jXA!9_L7
* W9n0Jv
* @author gw~%jD-2
*/ bHVAa#
public class CountBean { (uW/t1
private String countType; qcMVY\gi
int countId; i; Cs,Esnf
/** Creates a new instance of CountData */ M2HO!btf
public CountBean() {} ALvj)I`Al
public void setCountType(String countTypes){
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this.countType=countTypes; \Zc$X^}vN
} Q|QVm,m
public void setCountId(int countIds){ ?#;
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this.countId=countIds; ^2f'I iE
} 0q'd }D W
public String getCountType(){ L[l?}\
return countType; =OfU#i"c
} -YM#.lQ
public int getCountId(){ r>73IpJI
return countId; #p&&w1
} h 'VN& T,
} j.FA!4L
}
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CountCache.java 5v"r>q[
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/* :#D?b.=
* CountCache.java 5\93-e
* s2f95<B
* Created on 2007年1月1日, 下午5:01 jv$Y]nf
* RtVy^~=G
* To change this template, choose Tools | Options and locate the template under ' =MaO@ @
* the Source Creation and Management node. Right-click the template and choose MuNM)pyxp
* Open. You can then make changes to the template in the Source Editor. #qkokV6`
*/ ZeewGa^r
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package com.tot.count; HQHFD0hv
import java.util.*; KHwzQ<Z3
/** C!Cg.^;
* 9~+A<X]Hd
* @author 7sP;+G
*/ hsV+?#I
public class CountCache { v|5:;,I
public static LinkedList list=new LinkedList(); is=sV:j:
/** Creates a new instance of CountCache */ nQ|4.e;
public CountCache() {} zNSix!F
public static void add(CountBean cb){ W: Rs 0O
if(cb!=null){ @L^Fz$Sx
list.add(cb); D|8vS8p
} y,qP$5xiq
} !0ly1T 9
} Y.I-hl1<r
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CountControl.java p- 5)J&
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/* O%)@> 5#S
* CountThread.java RjS;Ck@;
* }~P%S(zB
* Created on 2007年1月1日, 下午4:57 fDc>E+,
* [8*Ovd
* To change this template, choose Tools | Options and locate the template under '\%c"?
* the Source Creation and Management node. Right-click the template and choose V:F;Nq%+j
* Open. You can then make changes to the template in the Source Editor. 6BIP;, M=
*/ Xx{ho4qq
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package com.tot.count; KTn,}7vZ
import tot.db.DBUtils; 8
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import java.sql.*; x_9<&Aj6
/** *8}Y0V\s
* =4GJYhj
* @author `|K,E
*/ b?Wg|D
public class CountControl{ K/RQ-xd4
private static long lastExecuteTime=0;//上次更新时间 H5t 9Mg|
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 J6x\_]1:*
/** Creates a new instance of CountThread */ 216+ tX5Z
public CountControl() {} M=[ /v/M=
public synchronized void executeUpdate(){ 4 -)'a} O
Connection conn=null; T1zft#1~
PreparedStatement ps=null; Ta #vD_QP
try{ u#5/s 8
conn = DBUtils.getConnection(); EubR]ckB
conn.setAutoCommit(false); SNP.n))
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); d_9Fc"C~
for(int i=0;i<CountCache.list.size();i++){ -1Y9-nn[m
CountBean cb=(CountBean)CountCache.list.getFirst(); gyH'92ck
CountCache.list.removeFirst(); /x.TF'Z*
ps.setInt(1, cb.getCountId()); &pwSd
ps.executeUpdate();⑴ #!p=P<4M
//ps.addBatch();⑵ 6cof Zc$
} s
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//int [] counts = ps.executeBatch();⑶ {#q']YDe`
conn.commit(); 4GJ1P2
}catch(Exception e){ 'B}pIx6k~
e.printStackTrace(); mhTpR0
} finally{ ZK5(_qW&i
try{ 3oX%tx
if(ps!=null) { 4X7y}F.J
ps.clearParameters(); 9@AGx<S1
ps.close(); %VYQz)yW
ps=null; G)gf +)W
} 8?] :>
}catch(SQLException e){} ~^/zCPy[w
DBUtils.closeConnection(conn); J5L P#o(V
} $mm =$.
} n+@}8;oeP
public long getLast(){ rUfW0
return lastExecuteTime; 3{_A zL
} 3WyK!@{
public void run(){ j&E4|g (
long now = System.currentTimeMillis(); 5@c,iU-L
if ((now - lastExecuteTime) > executeSep) { .lu:S;JSnS
//System.out.print("lastExecuteTime:"+lastExecuteTime); >JT{~SRB|Y
//System.out.print(" now:"+now+"\n"); U`q[5U"
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ^B@4 w\t
lastExecuteTime=now; zjgK78!<
executeUpdate(); gd<8RVA
} oTZ?x}Z1
else{ "?,3O2t
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); FD(zj ^*
} 992;~lBu
} 1!8*mk_R{
} 20m6-rkI<}
//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 P
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类写好了,下面是在JSP中如下调用。 ezTu1-m
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