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: B:Ec(USe
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CountBean.java _-$O6eZ
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/* MQ>.^]B]o
* CountData.java 6m"_=.k%
* %T4htZa
* Created on 2007年1月1日, 下午4:44 b1Bu5%bt,:
* b0|q@!z>
* To change this template, choose Tools | Options and locate the template under i>#[*.|P
* the Source Creation and Management node. Right-click the template and choose m`l3@Z
* Open. You can then make changes to the template in the Source Editor. ]@)T]
*/ /*\pm!]._^
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package com.tot.count; JfS:K'
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/** &"]Uh
* {Bk9]:'$5
* @author H-$ )@
*/ g"gh2#!D
public class CountBean { iLiEh2%P
private String countType; teh$W<C
int countId; jsL\{I^>
/** Creates a new instance of CountData */ 0O+[z9
public CountBean() {} YcW[BMy5h
public void setCountType(String countTypes){ U9GmkXRix
this.countType=countTypes; mVFz[xI
} -7\Rl3c
public void setCountId(int countIds){ SEsc"l8
this.countId=countIds; ckFnQhW
} R
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public String getCountType(){ Rd7[e^HSN
return countType; <20rxOEnf
} 04>dxw)8
public int getCountId(){ PI@/jh
return countId; Bwv@D4bii
} 7 \)OWp
} )2t!=
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CountCache.java c^0YuBps[
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/* {?tK]g#
* CountCache.java wG6@.;3
* E=!=4"rZF
* Created on 2007年1月1日, 下午5:01 @*SgeLeL
* 8;2UP`8s ?
* To change this template, choose Tools | Options and locate the template under am;)@<8~Q
* the Source Creation and Management node. Right-click the template and choose YYfX@`\
* Open. You can then make changes to the template in the Source Editor. S0?4}7`A
*/ J-C3k`%O
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package com.tot.count; ` QC
import java.util.*; Qx{k_ye`
/** $%~-p[)<(P
* 0\3mS{s
* @author nk.m Gny
*/ Z^? 1MJ:`
public class CountCache { U(#)[S,
public static LinkedList list=new LinkedList(); eHr|U$Rpo
/** Creates a new instance of CountCache */ oL?(;
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public CountCache() {} ?
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public static void add(CountBean cb){ +%vBDcf
if(cb!=null){ +c&n7
list.add(cb); <s/n8#i=H
} z~tCag8I(k
} rUZRYF4C
} <WXO].^
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CountControl.java 9$[I~I#z
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/* sjh>i>t
* CountThread.java P(OgT/7A
* &6!~Q,;K-
* Created on 2007年1月1日, 下午4:57 z.fh4p
* %JmRJpCvR
* To change this template, choose Tools | Options and locate the template under _ 4:@+{
* the Source Creation and Management node. Right-click the template and choose QP/6N9/
* Open. You can then make changes to the template in the Source Editor. [^wEKRt&
*/ _hP siZY9
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package com.tot.count; u6&<Bv
import tot.db.DBUtils; r(sQI#
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import java.sql.*; "-aak )7w
/** JNhHQvi\
* HU[a b
* @author 0Y rdu,c
*/ RiHOX&-7
public class CountControl{ Wn;B ~
private static long lastExecuteTime=0;//上次更新时间 q-c9YOz_
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 Xk#"rM< Y
/** Creates a new instance of CountThread */ 7P3PQ%:
public CountControl() {} b=:$~N@Y
public synchronized void executeUpdate(){ _isqk~ ul
Connection conn=null; TMt,\gTd
PreparedStatement ps=null; Nxk3uF^
try{ 4o,%}bo&
conn = DBUtils.getConnection(); HQi57QB
conn.setAutoCommit(false); >7@kwj-f)
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); =+um:*a.
for(int i=0;i<CountCache.list.size();i++){ a*4"j2j v
CountBean cb=(CountBean)CountCache.list.getFirst(); Lg[v-b=?I
CountCache.list.removeFirst(); QF^ _4Yn
ps.setInt(1, cb.getCountId()); YTBZklM
ps.executeUpdate();⑴ 'qD5
//ps.addBatch();⑵ Cj).
} cd8ZZ8L
//int [] counts = ps.executeBatch();⑶ Qd~M;L O"i
conn.commit(); gH87e
}catch(Exception e){ ;zy[xg.7
e.printStackTrace(); |~'D8 g:Ak
} finally{ J?/.|Y]e
try{ O6rrv,+_L
if(ps!=null) { u<8 f;C_
ps.clearParameters(); {"<6'2T3
ps.close(); ml7nt0{
ps=null; B35zmFX|}N
} :,.g_@wvG
}catch(SQLException e){} M6n9>aW4
DBUtils.closeConnection(conn); KP)BD;
} x;H#-^LxW=
} RB]K?
public long getLast(){ }7k!>+eQ
return lastExecuteTime; F\m
} ^B9rt\,q
public void run(){ y/'^r?
long now = System.currentTimeMillis(); -9BKa~ DVQ
if ((now - lastExecuteTime) > executeSep) { m9*Lo[EXO
//System.out.print("lastExecuteTime:"+lastExecuteTime); \EH:FM}l,
//System.out.print(" now:"+now+"\n"); o`^GUY}
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); H^jFvAI,8
lastExecuteTime=now; Lo,z7"8
executeUpdate(); wk {9
} q|PB[*T
else{ ]:* 8
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//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); StUiL>9T#
} k;V4%O
} {"33 .^=
} Q;O\tl
//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 F",]*>r
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类写好了,下面是在JSP中如下调用。 )k5lA=(Yr+
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<% U^_'e_)
CountBean cb=new CountBean(); yQwj[
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); m35Blg34
CountCache.add(cb); A`4Di8'Me
out.print(CountCache.list.size()+"<br>"); Q(lj&!?1k
CountControl c=new CountControl(); |_l\.
c.run(); >V~q`htth
out.print(CountCache.list.size()+"<br>"); }g WSV
%>