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: k]?z~ p
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CountBean.java {J~(#i
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/* -B1YZ/.rz"
* CountData.java T&r +G!2
* 8F zHNG
* Created on 2007年1月1日, 下午4:44 N5nvL)a~
* ,0!uem}1i
* To change this template, choose Tools | Options and locate the template under 'h-3V8m^e
* the Source Creation and Management node. Right-click the template and choose J=UZ){c>:.
* Open. You can then make changes to the template in the Source Editor. d5DP^u
*/ $]@O/[
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package com.tot.count; }B y)y;~
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/** c 9rVgLqn!
* fO].e"}
* @author ]7a;jNQu
*/ [6D>f?z
public class CountBean { FU%~9NKX
private String countType; I4)Nb WQ
int countId; ?75\>NiR
/** Creates a new instance of CountData */ dQ: ?<zZ
public CountBean() {} K7IyCcdB
public void setCountType(String countTypes){ Kb}MF9?:e
this.countType=countTypes; K~c^*;F
} 6Wj@r!u
public void setCountId(int countIds){ JE0?@PI$
this.countId=countIds; x6LjcRS|
} KNy`Lj)VPY
public String getCountType(){ [?-]PZ
return countType; ;}LJh8_
} RfKc{V
public int getCountId(){ hM~eJv
return countId; D7)(D4S4
} B4Q79gEh=
} KiQ(XNx
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CountCache.java 9"~9hOEct
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/* )8;{nqoC
* CountCache.java
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* )S^z+3p
* Created on 2007年1月1日, 下午5:01 Q6=MS>JW]w
* Y2<dM/b/
* To change this template, choose Tools | Options and locate the template under a\=-D:
* the Source Creation and Management node. Right-click the template and choose b\?3--q
* Open. You can then make changes to the template in the Source Editor. qgtn5]A
*/ A8J8u,u9
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package com.tot.count; L?!$EPr
import java.util.*; *ksb?|<Ot
/** &.zj5*J
* Q:mZ" i5
* @author =yo{[&Jz
*/ L[rpb.'FG
public class CountCache { @%c81rv?
public static LinkedList list=new LinkedList(); j")FaIM
/** Creates a new instance of CountCache */
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public CountCache() {} c15r':.5
public static void add(CountBean cb){ "3SWO3-x
if(cb!=null){ O}QFq14<+
list.add(cb); Rp0|zP,5
} +P|2m"UA
} vv &BhIf3
} 1] j^d
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CountControl.java X(]Zr
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/* }qAVN
* CountThread.java `fz,Lh*v
* =`-|&
* Created on 2007年1月1日, 下午4:57 =+<d1W`>0
* u,eZ6
* To change this template, choose Tools | Options and locate the template under #4><r.v3
* the Source Creation and Management node. Right-click the template and choose Nsn~@.UuSW
* Open. You can then make changes to the template in the Source Editor. b$Ln}<
*/ fD{II+T
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package com.tot.count; ~Q?!W0ZBE
import tot.db.DBUtils; CZY7S*fL
import java.sql.*; [![ G7H%f
/** EWA;L?g|A
* J*j5#V];
* @author =h|wwQE
*/ rnO0-h-;
public class CountControl{ +dw!:P&
private static long lastExecuteTime=0;//上次更新时间 %hc'dZ
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 1* ^'\W.
/** Creates a new instance of CountThread */ 0z7L+2#b^
public CountControl() {} `B:"6nW6
public synchronized void executeUpdate(){ o-z &7@3Hu
Connection conn=null; fywvJ$HD]L
PreparedStatement ps=null; k9mi5Oc
try{ *_1[[~Aw
conn = DBUtils.getConnection(); @uM EXP
conn.setAutoCommit(false); L,?/'!xV
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); h*3{6X#(/
for(int i=0;i<CountCache.list.size();i++){ A2NF<ZsD
CountBean cb=(CountBean)CountCache.list.getFirst(); G`F8!O(
CountCache.list.removeFirst(); g6%Z)5D]!
ps.setInt(1, cb.getCountId()); QL97WK\$
ps.executeUpdate();⑴ ;wR 'z$8
//ps.addBatch();⑵ RPH1''*!
} B76 v}O:
//int [] counts = ps.executeBatch();⑶ 44HiTWQS?l
conn.commit(); .'1SZe7O
}catch(Exception e){ /ZW&0E
e.printStackTrace(); _9@ >;]
} finally{ >.<ooWw
try{ YTQps&mD.
if(ps!=null) { -Wc~B3E|
ps.clearParameters(); _6MdF<Xb/
ps.close(); B[F-gq-
ps=null; Gf0,RH+
} u[")*\CP
}catch(SQLException e){} S@xXq{j
DBUtils.closeConnection(conn); Yp1bH+/u
} gcf6\f}\<
} Dx-KMiQ,"(
public long getLast(){ q+ pOrGh
return lastExecuteTime; U>P|X=)
} \4{2eU
public void run(){ XV>&F{
long now = System.currentTimeMillis(); inAAgW#s}
if ((now - lastExecuteTime) > executeSep) { <x0H@?f7
//System.out.print("lastExecuteTime:"+lastExecuteTime); zN~6HZ_:^
//System.out.print(" now:"+now+"\n"); |cDszoT
/
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 0q,pi qjO
lastExecuteTime=now; M T6/2d
executeUpdate(); P`jL]x
} {Dr@HP/x=s
else{ 33K*qaRAD
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); +}@8p[`)
} J!TBREK
} .A6lj).:
} HjA_g0u
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 p'f%%#I
% /}WUP^H
类写好了,下面是在JSP中如下调用。 B$vr'U
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<% o>?*X(+le
CountBean cb=new CountBean(); ~@4'HMQ
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); syPWs57pH
CountCache.add(cb); .lN s4e
out.print(CountCache.list.size()+"<br>"); !bU\zH
CountControl c=new CountControl(); DC Q^fZ/
c.run(); *5VXyt2
out.print(CountCache.list.size()+"<br>"); 2c(aO[%h9
%>