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: HaA2y
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CountBean.java `_+%
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/* :>K8oE
* CountData.java nw,XA0M3
* {JlSfJw!
* Created on 2007年1月1日, 下午4:44 *&doI%q
* e5$S2o~JF
* To change this template, choose Tools | Options and locate the template under wBI>H
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* the Source Creation and Management node. Right-click the template and choose #5yz~&
* Open. You can then make changes to the template in the Source Editor. a98J_^ n
*/ oxNQNJ!X
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package com.tot.count; _V,bvHWlM
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/** :k Kdda<g#
* &cZl2ynPi
* @author CLgfNrW~
*/ uN@El1ouY
public class CountBean { ?+G
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private String countType; @iBaJ"*,
int countId; c>%%'c
/** Creates a new instance of CountData */ ^i!I0Q2yd
public CountBean() {} vw6DHN)k
public void setCountType(String countTypes){ !,9;AMO
-
this.countType=countTypes; ")Qhg-l
} ;5tQV%V^Q
public void setCountId(int countIds){ 61Wh %8-
this.countId=countIds; H(tT8Q5i
} 1O2jvt7M
public String getCountType(){ Sb.%B^O
return countType; yYiu69v
} V*gh"gZ<
public int getCountId(){ F% z$^ m-
return countId; ~cul;bb#
} 88On{Kk.v
} V`m9+<.1 b
}v6@yU
CountCache.java
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/* zALtG<_t
* CountCache.java x7!gmbMfK'
* Ejj+%)n.
* Created on 2007年1月1日, 下午5:01 6,~]2H'zq
* y' RQ_Gi
* To change this template, choose Tools | Options and locate the template under >';UF;\5]Q
* the Source Creation and Management node. Right-click the template and choose q0{ _w
* Open. You can then make changes to the template in the Source Editor. +1nzyD_E
*/ W
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package com.tot.count; e=`=7H4P
import java.util.*; "t%Jj89a\
/** !3)WW)"!r
* 6h7TM?lt
* @author &3 *#h
*/ r"!xI
public class CountCache { ;r}yeISf
public static LinkedList list=new LinkedList(); sBa&]9>m
/** Creates a new instance of CountCache */ @?*;
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public CountCache() {} ^$s&bH'8
public static void add(CountBean cb){ y I} >
if(cb!=null){ }H:wgy`
list.add(cb); LZDJ\"a-
} Y)2#\ F
} (qzBy \\p
} hv *XuT/
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CountControl.java 3.6Gh|7
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/* fZb}-
* CountThread.java *tfD^nctO
* vZ1?4hG
* Created on 2007年1月1日, 下午4:57 Lk.tEuj=82
* QzxEkTc;
* To change this template, choose Tools | Options and locate the template under ?2,{+d |
* the Source Creation and Management node. Right-click the template and choose $r)NL
* Open. You can then make changes to the template in the Source Editor. n(W&GSj|u9
*/ [l}H%S
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package com.tot.count; }$b!/<7FD
import tot.db.DBUtils; S0`u!l89(
import java.sql.*; aKintb}n
/** |nBs(>b
* Q5HSik4
* @author \_x~lRqJJ
*/ Vwb_$Yi+]
public class CountControl{ FuC\qF
private static long lastExecuteTime=0;//上次更新时间 TE6]4E*
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 -""(>$b2
/** Creates a new instance of CountThread */ ;;+h4O )
public CountControl() {} #gVWLm<
public synchronized void executeUpdate(){ zUq(bD
Connection conn=null; Qna*K7kv
PreparedStatement ps=null; x@3cZd0j#
try{ EiVVVmm!
conn = DBUtils.getConnection(); _&r19pY
conn.setAutoCommit(false); \1hQ7:f;\
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); O8~RfB
for(int i=0;i<CountCache.list.size();i++){ L{oG'aK4
CountBean cb=(CountBean)CountCache.list.getFirst(); &ET$ca`j#
CountCache.list.removeFirst(); $Z3{D:-)
ps.setInt(1, cb.getCountId()); [5]n,toAh
ps.executeUpdate();⑴ pj$kSS|m6-
//ps.addBatch();⑵ k*D8IB
} >[;L.
//int [] counts = ps.executeBatch();⑶ 8erG](
conn.commit(); +J#8wh
}catch(Exception e){ TfHL'u9B
e.printStackTrace(); 4s@Tn>%SP
} finally{ ^SK!?M
try{ *c
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if(ps!=null) { HPg%v|
ps.clearParameters(); N`~f77G
ps.close(); +S WtHj7e
ps=null; ]Ljb&*IEj
} Q\>mg*79
}catch(SQLException e){} X#HH7V>
DBUtils.closeConnection(conn); lOM8%{.'_x
} eAStpG"*
} .osG"cS
public long getLast(){
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return lastExecuteTime; 8`6G_:&X
} 2A:&Cqo
public void run(){ ;y-:)7J
long now = System.currentTimeMillis(); j{D tjV8
if ((now - lastExecuteTime) > executeSep) { m&s>Sn+
//System.out.print("lastExecuteTime:"+lastExecuteTime); AD+OQLG]`
//System.out.print(" now:"+now+"\n"); 7 IJn9 b
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); +d7Arg!m
lastExecuteTime=now; aKE`nA0\B
executeUpdate(); kP'm$+1or
} p:W{c/tV
else{ 5 D=r7
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); -9;?k{{[T
} GFju:8P?
} +o):grWvQ
} zszmG^W{
//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 |6;-P&_n
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类写好了,下面是在JSP中如下调用。 K]uH7-YvL/
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<% zl|
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CountBean cb=new CountBean(); 62MQ+H
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); wqT9m*VK
CountCache.add(cb); |3 Iug
out.print(CountCache.list.size()+"<br>"); 78r0K 5=
CountControl c=new CountControl(); Xvoz4'Gme
c.run(); 1Wiz0X/
out.print(CountCache.list.size()+"<br>"); 1z0|uc
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