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: ba|x?kz
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CountBean.java >=^g%K$L6J
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/* 1YR;dn
* CountData.java R6dw#;6{I
* |tz1'YOB
* Created on 2007年1月1日, 下午4:44 |Z6rP-
* N^q*lV#kob
* To change this template, choose Tools | Options and locate the template under x*5'
6
* the Source Creation and Management node. Right-click the template and choose liFNJd`|o+
* Open. You can then make changes to the template in the Source Editor. `d6
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*/ e.G&hJr
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package com.tot.count; K]zBPfx
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/** NAV}q<@v
* V'pNo&O=
* @author iKV;>gF,)v
*/ E5 H6&XU
public class CountBean { jD0^,aiG
private String countType; U/,`xA;v>
int countId; *r p@`W5
/** Creates a new instance of CountData */ wQb")3dw
public CountBean() {} 2tCep
public void setCountType(String countTypes){ g]iWD;61
this.countType=countTypes; EiI3$y3;
} t d q;D
public void setCountId(int countIds){ T*\'G6e
this.countId=countIds; * kgbcU f8
} *La*j3|:
public String getCountType(){ dGQxGt1
return countType; 8^p/?R^bu
} ^Ot+,l)
public int getCountId(){ dTyTj|"x{
return countId; (rt DT
} Um;ReJ8z
} sq*R)cZ
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CountCache.java 0KnlomuH2
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/* :g'"*VXYB
* CountCache.java 1 dz&J\|E#
* /-E>5 w U
* Created on 2007年1月1日, 下午5:01 ]N-K`c]
* |k)h' ?
* To change this template, choose Tools | Options and locate the template under F0bmGDp@-
* the Source Creation and Management node. Right-click the template and choose ho#]?Z#
* Open. You can then make changes to the template in the Source Editor. B^U5=L[:p
*/ Ha$|9li`
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package com.tot.count; f!P.=Qo[=
import java.util.*; "My \&0-
/** ,V)yOLApVj
* vkE6e6,Qc
* @author "<3PyW?zt
*/ ^O#,%>1J
public class CountCache { y2\, L
public static LinkedList list=new LinkedList(); T9{94Ra
/** Creates a new instance of CountCache */ VyCBJK
public CountCache() {} .zlUN0oe
public static void add(CountBean cb){ ; z :}OD
if(cb!=null){ h_?D%b~5
list.add(cb); h\C
} 9g"a`a?c
} \PU|<Ru.
} V5K`TC^
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CountControl.java PAH;
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/* g[-'0d\1
* CountThread.java fbNVmjb$)
* 93)&
* Created on 2007年1月1日, 下午4:57 Da_g3z
* 0%k`*8
* To change this template, choose Tools | Options and locate the template under RFDwL~-p
* the Source Creation and Management node. Right-click the template and choose ;.!AX|v
* Open. You can then make changes to the template in the Source Editor. ?&)<h_R4p
*/ ;*wZgl
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package com.tot.count; DB:Ia5|*i
import tot.db.DBUtils; i4'?/UPc
import java.sql.*; kxWf1hIz0
/** %l,p />r
* O9=vz%
* @author 8NPt[*
*/ Z?G-~3]e
public class CountControl{ ocAoqjlT[
private static long lastExecuteTime=0;//上次更新时间 d
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private static long executeSep=60000;//定义更新间隔时间,单位毫秒 a[xEN7L~4D
/** Creates a new instance of CountThread */ 1A< O
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public CountControl() {} v)d\
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public synchronized void executeUpdate(){ /0!6;PC<
Connection conn=null; 50l=B]M
PreparedStatement ps=null; ~k+-))pf
try{ [#)-F_S
conn = DBUtils.getConnection(); `WC~cb\
conn.setAutoCommit(false); 6jRF[N8
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); xO'1|b^&
for(int i=0;i<CountCache.list.size();i++){ /=lrdp!a
CountBean cb=(CountBean)CountCache.list.getFirst(); ;,JCA#
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CountCache.list.removeFirst(); _&.CI6
ps.setInt(1, cb.getCountId()); 8>T
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ps.executeUpdate();⑴ t 4{{5U'\
//ps.addBatch();⑵ N02N
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} fi:Z*-
//int [] counts = ps.executeBatch();⑶ Z99%uI3
conn.commit(); hi*\5(uH
}catch(Exception e){ rQ;m|@
e.printStackTrace(); cDxjD5E
} finally{ Kv{i_%j
try{ w \i#
if(ps!=null) { 9@Cqg5Kx'
ps.clearParameters(); -1:yqF.x
ps.close(); $vTU|o>|
ps=null; 1}QU\N(t
} hR[Qdu6r
}catch(SQLException e){} Q^DKKp
DBUtils.closeConnection(conn); %S]5wR6;_
} (VWTYG7
} gUy >I(
public long getLast(){ @PU%BKe
return lastExecuteTime; ,N<xyx.
} xx#;)]WT
public void run(){ 9%$4Ux*q
long now = System.currentTimeMillis(); "So+
if ((now - lastExecuteTime) > executeSep) { `Q,moz
//System.out.print("lastExecuteTime:"+lastExecuteTime); Qi w "x,
//System.out.print(" now:"+now+"\n"); ds4ERe /
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); iU~oPp[e
lastExecuteTime=now; Zc{at}{
executeUpdate(); {O]Cj~}
} DKF`uRvGN:
else{ <lB^>Hfu
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); oZmni9*SD
} ORA+>
} @L=xY[&{
} ZvkO#j
//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
}Rt?p8p
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类写好了,下面是在JSP中如下调用。 B7fURL
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<% 'eLO#1Ipf
CountBean cb=new CountBean(); U9SByqa1
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); b_|`jHes
CountCache.add(cb); >(|T]u](q
out.print(CountCache.list.size()+"<br>"); W-<C%9O!
CountControl c=new CountControl(); mKvk6OC
c.run(); -Z-|49I/mN
out.print(CountCache.list.size()+"<br>"); a^@6hC>sr
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