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: E@"+w,x)
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CountBean.java ZP*Hx
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/* k\Oy\z@
* CountData.java 5wRDH1z@{
* >9F,=63A
* Created on 2007年1月1日, 下午4:44 DyG3|5s1R
* 8;p6~&).C~
* To change this template, choose Tools | Options and locate the template under kX\t0'=]
* the Source Creation and Management node. Right-click the template and choose J7emoD[
* Open. You can then make changes to the template in the Source Editor. O~9
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*/ %fh
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package com.tot.count; 2#@S6zc
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/** :cG_aOkid
* }{:H0)H*
* @author f&H):.
*/ iYHD:cg)~
public class CountBean { =bZ>>-<
private String countType; fV
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int countId; e<l Wel
/** Creates a new instance of CountData */ DM! vB+j+,
public CountBean() {} 9Q^>.^~^
public void setCountType(String countTypes){ aT(Pf7
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this.countType=countTypes; v/8K?$"q
} tn6\0_5n
public void setCountId(int countIds){ kxhvy,t
this.countId=countIds; 0^]E-Zf
}
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public String getCountType(){ %D\TLY
return countType; JE9|;A
} el.;T*Wn
public int getCountId(){ B~lrd#qC
return countId; j3P)cz-0/L
} er,R}v
} "Hg.pDNZ
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CountCache.java Bb]pUb
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/*
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* CountCache.java @?3u|m |Z
* :"3WCB
* Created on 2007年1月1日, 下午5:01 Bg"b,&/^u
* *@dRL3c^=
* To change this template, choose Tools | Options and locate the template under 4kT| /bp
* the Source Creation and Management node. Right-click the template and choose 2hw3+o6
* Open. You can then make changes to the template in the Source Editor. G|'DAj%
*/ '+Gt+Gq+
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package com.tot.count; N3MMxm_u
import java.util.*; O%tlj@?
/** jWiB_8-6
* $9+}$lpPd
* @author IcoK22/
*/ ^EjZ.#2l;
public class CountCache { TWQf2
public static LinkedList list=new LinkedList(); `;*Wt9
/** Creates a new instance of CountCache */ _wCp.[3?t
public CountCache() {} ub{<m^|)
public static void add(CountBean cb){ gr4Hh/V
if(cb!=null){ D+LeZBJ
list.add(cb); yps7MM-r
} [O&2!x
} ]3NH[&+
} "|]'\4UdzQ
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CountControl.java 2!-ZNd:(+
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/* R6h(mPYA
* CountThread.java 3 {\b/NL$
* z62e4U][
* Created on 2007年1月1日, 下午4:57 >9Fs)R]P
* S@z$,}Yc`<
* To change this template, choose Tools | Options and locate the template under d\3L.5]X
* the Source Creation and Management node. Right-click the template and choose xQ* U9Wt;T
* Open. You can then make changes to the template in the Source Editor. )T(xQ2&r4
*/ R4_4 FEo
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package com.tot.count; iPa!pg4m
import tot.db.DBUtils; 8 %Lq~lk
import java.sql.*; Gz+Bk5#{
/** z(:0@ 5
* zn_ InxR
* @author %njX'7^u
*/ uPsn~>(4
public class CountControl{ a/NmM)
private static long lastExecuteTime=0;//上次更新时间 u!k\W{
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 S3MMyS8
/** Creates a new instance of CountThread */ G{knO?BK
public CountControl() {}
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public synchronized void executeUpdate(){ sI@m"A
Connection conn=null;
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PreparedStatement ps=null; }wC
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try{ 14]!LgH
conn = DBUtils.getConnection(); w[uK3A v
conn.setAutoCommit(false); YS{])+s
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ]ch cRc[!
for(int i=0;i<CountCache.list.size();i++){ fS>W-
CountBean cb=(CountBean)CountCache.list.getFirst(); W7WHH \L/O
CountCache.list.removeFirst(); ^IjKT
ps.setInt(1, cb.getCountId()); fYuJf,I[f
ps.executeUpdate();⑴ #y&3`N z3
//ps.addBatch();⑵ j_L 'Ztu3
} R^1sbmwk
//int [] counts = ps.executeBatch();⑶ 'D1
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conn.commit(); js^@tgf$x&
}catch(Exception e){ G':mc{{
e.printStackTrace(); f#ID:Ap3
} finally{ =V5<>5"M?
try{ T@U_;v|rf
if(ps!=null) { E=Ah_zKU
ps.clearParameters(); ?uc=(J+6
ps.close(); 38L8AJqD
ps=null; E&Pv:h,pV&
} <?yAIhgN*
}catch(SQLException e){} 8do]5FE
DBUtils.closeConnection(conn); ^cZF#%k
} 6Hi3h{
} jJQ6]ucwa
public long getLast(){ \tye:!a?;@
return lastExecuteTime; ^'lx5+-
} 8v8?D8\=|
public void run(){ 5,:>.LRA
long now = System.currentTimeMillis(); .</d$FM JE
if ((now - lastExecuteTime) > executeSep) { c+f~>AaI
//System.out.print("lastExecuteTime:"+lastExecuteTime); #|v\UJ:Pf/
//System.out.print(" now:"+now+"\n"); L}h?nWm8
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ~%qHJ4C
lastExecuteTime=now; _"&b%!
executeUpdate(); azr|Fz/
} %Nwap~=H;
else{ S)iv k x
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 3Nd&*QSV
} )-xx$0mL-
} EFW'D=&h8
} <ap%+(!I
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 ^o,P>u!9
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类写好了,下面是在JSP中如下调用。 f$Nz).(
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<% |#D3~au
CountBean cb=new CountBean(); Dkayk
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); EA7 8&
CountCache.add(cb); 7"yA~e,l
out.print(CountCache.list.size()+"<br>"); skh6L!6*<
CountControl c=new CountControl(); b/:9^&z
c.run(); v?,_SVgAi
out.print(CountCache.list.size()+"<br>"); fJBp,{0
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