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: O^4:4tRpt
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CountBean.java Y-@K@Zu]?
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/* N ~g'Z
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* CountData.java % nP13V]
* KS1Z&~4
* Created on 2007年1月1日, 下午4:44 LYkW2h`JQ
* *w59BO&M4
* To change this template, choose Tools | Options and locate the template under z9YC9m)jK
* the Source Creation and Management node. Right-click the template and choose 44mYs`]
* Open. You can then make changes to the template in the Source Editor. L&Bc-kMH
*/ Nx;U]O6A
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package com.tot.count; R.*KaCA
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/** -GDX#A-J
* -`FTWH
* @author >j_,3{eJ
*/ TR5"K{WDx
public class CountBean { 4=>/x90y
private String countType; C B=H1+
int countId; r2qxi'
/** Creates a new instance of CountData */ Pc`d@q
public CountBean() {} tlQ3BKp
public void setCountType(String countTypes){ 4 )*8&
this.countType=countTypes; S;MS,R
} Fla,#uB
public void setCountId(int countIds){ \zR{D}aS
this.countId=countIds; Elh: %dr Q
} G?8LYg!-
public String getCountType(){ 8@|+-)t
return countType; DL_2%&k/
} 2Do^N5y
public int getCountId(){ sr
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return countId; 8BhLO.(<O
} ;Q:^|Fw!F
} Wb68" )$
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CountCache.java <hkg~4EKc
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/* }>6=(!
* CountCache.java kNMhMEez
* Se%FqI
* Created on 2007年1月1日, 下午5:01 @w[WG:-+
* P'KaW u9z
* To change this template, choose Tools | Options and locate the template under KaZ*HPe(
* the Source Creation and Management node. Right-click the template and choose 12~zS
* Open. You can then make changes to the template in the Source Editor. 2N9
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*/ #&\^{Z
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package com.tot.count; N9r02c
import java.util.*; 2d >kc2=*
/** ,i;kAy)
* w6'o<=
* @author nMNAn}~*M
*/ sFC&DTb?
public class CountCache { l&dHH_m3
public static LinkedList list=new LinkedList(); Jb#*QJ=
/** Creates a new instance of CountCache */ "O<JVC{m
public CountCache() {} 7,d^?.~S
public static void add(CountBean cb){ $C##S@
if(cb!=null){ cH.T6u_%
list.add(cb); |g}!
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} zT6ng#
} tV9BVsN
} $Ud-aRlD
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CountControl.java EtWpB g
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/* xO`w|k
* CountThread.java {
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* o) `zb?
* Created on 2007年1月1日, 下午4:57 p^Kp= z
* vtc} )s\
* To change this template, choose Tools | Options and locate the template under lNs 'jaD
* the Source Creation and Management node. Right-click the template and choose l[.*X
* Open. You can then make changes to the template in the Source Editor. U{q6_z|c
*/ :CV!:sUm
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package com.tot.count; 9TjAEeU
import tot.db.DBUtils; .Kv>*__-Q
import java.sql.*; :@I?JSi
/** mR,p?[P
* IvTtQq
* @author WIb\+!
*/ WLV'@$ <|(
public class CountControl{ 4tz8^z[Kw
private static long lastExecuteTime=0;//上次更新时间 Uq 2Uv
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 Is` S
/** Creates a new instance of CountThread */ 5@" bx=
public CountControl() {} 6d&BN7B
public synchronized void executeUpdate(){ ;_R;P;<
Connection conn=null; jJg9M'@2!
PreparedStatement ps=null; sZ{Kl\1@
try{ =iC5um:
conn = DBUtils.getConnection(); [R)?93
conn.setAutoCommit(false); z%Ywjfn'
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); E
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for(int i=0;i<CountCache.list.size();i++){ s1<_=sfnT
CountBean cb=(CountBean)CountCache.list.getFirst(); R|%
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CountCache.list.removeFirst(); B08q/qi
ps.setInt(1, cb.getCountId()); f&bY=$iff
ps.executeUpdate();⑴ UB@>i3
//ps.addBatch();⑵ Jvw~b\
} :
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//int [] counts = ps.executeBatch();⑶ 'm# -)R!
conn.commit(); j
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}catch(Exception e){ W1f]A#t<
e.printStackTrace(); wb2N$Ew=
} finally{ *YZ'Uy?
try{ 41>Bm*if
if(ps!=null) { 1 b+B
ps.clearParameters(); HNxJ`x~Z~
ps.close();
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ps=null; ELeR5xT
} <1.].A@b*
}catch(SQLException e){} ])!|b2:s3
DBUtils.closeConnection(conn); u`$,S&Er
} '\H {Y[
} 6C9KT;6
public long getLast(){ EJO:3aKa
return lastExecuteTime; L,of@>
} ,GS8Gu
public void run(){ BhJqMK>'S
long now = System.currentTimeMillis(); d i`}Y&
if ((now - lastExecuteTime) > executeSep) { =L{lt9qQz
//System.out.print("lastExecuteTime:"+lastExecuteTime); _SjS^z~
//System.out.print(" now:"+now+"\n"); a"&@G=M@d
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); "tBdz V
lastExecuteTime=now; 2GLq#")P
executeUpdate(); &_HSrU
} W}EI gVHs
else{ #M&rmKv)g
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); @g(N!n~
} HUr;ysw
} .!RBhLH_g
} PA5ET@mD
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 MI0'ou8l
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类写好了,下面是在JSP中如下调用。 u{"o*udU
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<% N*$<Kjw
CountBean cb=new CountBean(); x~!B.4gT2
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); H@bra~k-
CountCache.add(cb); V:9| 9$G
out.print(CountCache.list.size()+"<br>"); J4 .C"v0a
CountControl c=new CountControl(); C_dsYuQ5R
c.run(); ~;_]U[eOL
out.print(CountCache.list.size()+"<br>"); GeWB"(t
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