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: 9<ev]XaSl
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CountBean.java rfdT0xfcU
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/* LK'|sO>|
* CountData.java 85Hb~|0
* ;P{HePs=)
* Created on 2007年1月1日, 下午4:44 _26~<gU8
* itmdY!;<
* To change this template, choose Tools | Options and locate the template under dsh S+d
* the Source Creation and Management node. Right-click the template and choose OEN!~-u
* Open. You can then make changes to the template in the Source Editor. Y^Olcz
*/ w/`I2uYu
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package com.tot.count; p+;[i%`
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/** A\jX #gg
* RU1+-
* @author \v'\
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*/ N!fTt,
public class CountBean { 1qw*mV;W)_
private String countType; ]i3 1@O
int countId; 3',|HA /x
/** Creates a new instance of CountData */ }BpCa6SAs
public CountBean() {} lUR7zrwJ]o
public void setCountType(String countTypes){ qDQ$Zq[
this.countType=countTypes; R0n#FL^E
} 8p?Fql}F[
public void setCountId(int countIds){ %z(nZ%,Z
this.countId=countIds; BmRk|b
} @} 61D
public String getCountType(){ F .(zS(q
return countType; ;eG,T-:
} L%[om c?
public int getCountId(){ uH}cvshv
return countId; wi]F\ q"Y^
} :CQ-?mT^LA
} _dT,%q
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CountCache.java ~
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/* b|cUKsL5
* CountCache.java ng-g\&-
* z]NzLz9VfL
* Created on 2007年1月1日, 下午5:01 `|1#Vuk
* |g3a1El
* To change this template, choose Tools | Options and locate the template under F0O/SI(cA
* the Source Creation and Management node. Right-click the template and choose a|*{BlY
* Open. You can then make changes to the template in the Source Editor. ov{
*/ uIG,2u,
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package com.tot.count; wgK:^DP
import java.util.*; 6w
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/** h|_E>6d)
* R).?lnS
* @author qjsS2,wM
*/ [dK5kO
public class CountCache { GgoPwl#{
public static LinkedList list=new LinkedList(); a)+;<GZ~
/** Creates a new instance of CountCache */ H0zKL]D'>
public CountCache() {} Fu*~{n
public static void add(CountBean cb){ ?F@0"qi
if(cb!=null){ hcvWf\4'#q
list.add(cb); >i> %@
} ay\ e#)
} U{2[nF
} ~>af"<
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CountControl.java NArql
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/* : GZx-
* CountThread.java ?N
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* v'"0Ya
* Created on 2007年1月1日, 下午4:57 =tJ}itcJ'
* pq 4/>WzE
* To change this template, choose Tools | Options and locate the template under $"d< F3k
* the Source Creation and Management node. Right-click the template and choose }{J5)\s9
* Open. You can then make changes to the template in the Source Editor. kxJ! #%w
*/ 3x=f}SO&
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package com.tot.count; hrpql_9.
import tot.db.DBUtils; #S57SD
import java.sql.*; =Fq"lq %
/** "t4$%7L]
* k^
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* @author eIzT(3(
*/
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public class CountControl{ de?Bn+mvi.
private static long lastExecuteTime=0;//上次更新时间 ]]\\Y|0
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 :27GqY,3sK
/** Creates a new instance of CountThread */ ,k*g`OTW
public CountControl() {} l2)) StEm
public synchronized void executeUpdate(){ WUQlAsme
Connection conn=null; YQyf:xJ
PreparedStatement ps=null; mHqw,28}
try{ 'N?,UtG R
conn = DBUtils.getConnection(); >tf y\P Y:
conn.setAutoCommit(false); UN7>c0B
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); jG"n);WF
for(int i=0;i<CountCache.list.size();i++){ I`?6>Z+%)
CountBean cb=(CountBean)CountCache.list.getFirst(); ?U~9d"2=
CountCache.list.removeFirst(); <P)vx
ps.setInt(1, cb.getCountId()); K,7IBv,B[
ps.executeUpdate();⑴ k_p4 f %9
//ps.addBatch();⑵ xef@-%mcoy
} *_
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//int [] counts = ps.executeBatch();⑶ D<=:9
conn.commit(); nE!h&}(
}catch(Exception e){ |K(j}^1k
e.printStackTrace(); sb"etc`w%-
} finally{ 1(z&0Y ;
try{ t(-`==.R
if(ps!=null) { J. ;9-
ps.clearParameters(); I:4m]q b
ps.close(); $F|3VQ~
ps=null; [whX),3>
} ={[s)G
}catch(SQLException e){} VKcO]_W1
DBUtils.closeConnection(conn); Mqu>#lL
} q*,g
} (E v/R%Z
public long getLast(){ wAC*D=Qj
return lastExecuteTime; bLrC_
} 2f'3Vjp~G
public void run(){ | |=q"h3(
long now = System.currentTimeMillis(); &tT*GjPwg;
if ((now - lastExecuteTime) > executeSep) { Tw|cg B
//System.out.print("lastExecuteTime:"+lastExecuteTime); PNwXZ/N%
//System.out.print(" now:"+now+"\n"); -e6~0%X
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); N/ 7Q(^
lastExecuteTime=now; E1(2wJ-3"
executeUpdate(); 2!Ip!IQ:
} ZJCD)?]=3
else{ ZP>KHiA
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); >7yOu!l
} >syQDB
} D^+#RR'#,
} 86bl'FdKS
//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 Tx)X\&ij&
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类写好了,下面是在JSP中如下调用。 u{F^Ngy
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<% 's.%rre%
CountBean cb=new CountBean(); UZ8
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 8!a6)Zeux
CountCache.add(cb); Q;m:o8Q5
out.print(CountCache.list.size()+"<br>"); #/u% sX`#y
CountControl c=new CountControl(); &/K:zWk3mx
c.run(); 7X\azL
out.print(CountCache.list.size()+"<br>"); !&f(Xs
%>