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: T854}RX[{
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CountBean.java \me-#: Gu
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/* UQnv#a>
* CountData.java ^~W s4[Guo
* GB{Q)L
* Created on 2007年1月1日, 下午4:44 ,
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* G5*_
* To change this template, choose Tools | Options and locate the template under xM13OoU
* the Source Creation and Management node. Right-click the template and choose sfR0wEqI
* Open. You can then make changes to the template in the Source Editor. Fiaeo0
*/ rq|>z .
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package com.tot.count; 3Y=uBl
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/** N >k,"=N/
* MrhJk
* @author Hh'o:j(^
*/ vPM2cc/o
public class CountBean { 9&Ny;oy#6
private String countType; AME<V-5
int countId; T;#:Y
/** Creates a new instance of CountData */ FB
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public CountBean() {} Am=O-;
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public void setCountType(String countTypes){ I 8 Ls_$[
this.countType=countTypes; 0pA>w8 mh
} A?H.EZ
public void setCountId(int countIds){ aj}#~v1
this.countId=countIds;
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} VL2ACv(
public String getCountType(){ UQ~gjnb[c
return countType; 3$PGLM
} pXf5/u8&
public int getCountId(){ S<>u
return countId; s=1w6ZLD
} ;_E][m
} (5>IF,}!L
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CountCache.java e89IT*
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/* 7vEZb.~4z
* CountCache.java 79}Qj7
* .`+N+B(4
* Created on 2007年1月1日, 下午5:01 {oRR]>
* Gt;U9k|i
* To change this template, choose Tools | Options and locate the template under m-R`(
* the Source Creation and Management node. Right-click the template and choose yD(v_J*
* Open. You can then make changes to the template in the Source Editor. _Sult;y"u
*/ ^i6`w_ /
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package com.tot.count; \"l/D?+Q
import java.util.*; 2$1D+(5;
/** 0]2@T=*kTY
* *7K)J8kq
* @author 1VB{dgr
*/ aKw7m={
public class CountCache { _}Ec[c
public static LinkedList list=new LinkedList(); qQe23,x@5
/** Creates a new instance of CountCache */ kRB2J3Nt.
public CountCache() {} %-3wR@
public static void add(CountBean cb){ y5N,~@$r
if(cb!=null){ {
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list.add(cb); y-vQ4G5F|
} }bYk#6KX
} rNeSg=j
} Q3aZB*$K
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CountControl.java \ O+Hmi^
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/* OB\jq!"
* CountThread.java [-w+ACV~
* ~%u;lr
* Created on 2007年1月1日, 下午4:57 ePe/@g1K*
* "U
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* To change this template, choose Tools | Options and locate the template under hlBqcOpkKg
* the Source Creation and Management node. Right-click the template and choose )}4xmf@gl
* Open. You can then make changes to the template in the Source Editor. cfUG)-]P~
*/ AHdh]pfH
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package com.tot.count; jmva0K},SE
import tot.db.DBUtils; 99?:
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import java.sql.*; lU% L
/** ]L9$JTGF`w
* {KM5pK?,BJ
* @author q|kkdK|N/Y
*/ VB@M=ShKK
public class CountControl{ kUQdi%3yY;
private static long lastExecuteTime=0;//上次更新时间 ~19&s~
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 9Xeg&Z|!
/** Creates a new instance of CountThread */ THz=_L6
public CountControl() {} IW- BY =C
public synchronized void executeUpdate(){ 1n EW'F
Connection conn=null; L=<{tzTc
PreparedStatement ps=null; ;p/$9b.0:
try{ $qfNEAmDf\
conn = DBUtils.getConnection(); PVX23y;
conn.setAutoCommit(false); eC*-/$D
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); Gcd'- 1
for(int i=0;i<CountCache.list.size();i++){ $D~vuA7
CountBean cb=(CountBean)CountCache.list.getFirst(); uDsof?z
CountCache.list.removeFirst(); lwp(Pq
ps.setInt(1, cb.getCountId()); Ib0@,y S[
ps.executeUpdate();⑴ c~{)vL0K
//ps.addBatch();⑵ H@BU/{
} +BkmI\
//int [] counts = ps.executeBatch();⑶ afj[HJbY
conn.commit(); t^(wbC
}catch(Exception e){ y<*/\]t9L[
e.printStackTrace(); V"Y-|R
} finally{ c_)lTI4
try{ w$z]Z-
if(ps!=null) { L(\o66a-rV
ps.clearParameters(); bs\7 juHt
ps.close(); OjBg$f~0F
ps=null; nZ~J&QK-
} >e9xM Gv
}catch(SQLException e){} gukKa
DBUtils.closeConnection(conn); 4: S-
} 3NxwQ,~
} +G[N
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public long getLast(){ O`Ge|4
return lastExecuteTime; ~6O<5@k
} GN@(!V#/4
public void run(){ K*fh`Kz
long now = System.currentTimeMillis(); U8icP+Y
if ((now - lastExecuteTime) > executeSep) { o~={M7m
//System.out.print("lastExecuteTime:"+lastExecuteTime); $C~OV@I
//System.out.print(" now:"+now+"\n"); x/xd
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 9ZXEy }q57
lastExecuteTime=now; 3ew`e"s
executeUpdate(); ;-@v1I;
} 2JS&zF
else{ _S;Fs|p_
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); <R@w0b>
} UsBtk
} j5]6CG_
} gDBdaxR<
//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
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类写好了,下面是在JSP中如下调用。 $ru()/pI)z
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<% oJbMUEQQq
CountBean cb=new CountBean(); w8>
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); t&L+]I'P3
CountCache.add(cb); DSc:>G
out.print(CountCache.list.size()+"<br>"); p:CpY'KV_
CountControl c=new CountControl(); z 2Rg`1B
c.run(); )TV{n#n
out.print(CountCache.list.size()+"<br>"); Y76U htYH
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