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: n^{h@u
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CountBean.java 8~Zw"
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/* O(%6/r`L,k
* CountData.java 3\P*"65
* Gu$J;bXVj
* Created on 2007年1月1日, 下午4:44 e6_8f*o|s
* pEcYfj3M
* To change this template, choose Tools | Options and locate the template under L%$-?O|
* the Source Creation and Management node. Right-click the template and choose 7:LEf"vRZ
* Open. You can then make changes to the template in the Source Editor. xP>cQEL ot
*/ l9|K,YVW
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package com.tot.count; HEFgEYlO
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/** Ot47.z
* O6?{@l
* @author IYq#|^)5+
*/ R3og]=uFzm
public class CountBean { AC
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private String countType; U{ 0~&
int countId; a_S`$(7k
/** Creates a new instance of CountData */ &Cj~D$kDEu
public CountBean() {} S[$9_J f
public void setCountType(String countTypes){ _PPC?k{z!
this.countType=countTypes; j$_?g!I=gK
} ^cPVnl
public void setCountId(int countIds){ lbt8S.fx
this.countId=countIds; D1-w>Y#
} ]s5e[iS
public String getCountType(){ R2~y<^.V`Y
return countType; 5>%^"f
} NX%1L!
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public int getCountId(){ 6|q"lS*$S
return countId; q
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} Peph..8 Z
} y>t:flD*
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CountCache.java ;rT/gwg!
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/* tx[;& ;
* CountCache.java 7Dssr [
* Eu&$Rq}
* Created on 2007年1月1日, 下午5:01 tgCp2`n
* U1/I(w
* To change this template, choose Tools | Options and locate the template under +~G:z|k
* the Source Creation and Management node. Right-click the template and choose f@ |[pT
* Open. You can then make changes to the template in the Source Editor. [Uq`B&F:
*/ S[9b
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package com.tot.count; ] +%`WCr9
import java.util.*; NVkYm+J#
/** ~b#<HG\,,
* t*Ro2QZ
* @author f2gh|p`
*/ -a_qZ7
public class CountCache { }*9F `=%F
public static LinkedList list=new LinkedList(); ]7k:3"wH
/** Creates a new instance of CountCache */ ~ u1~%
public CountCache() {} t1iz5%`p}
public static void add(CountBean cb){ |7,$.MK-@
if(cb!=null){ uZ_?x~V/
list.add(cb); ]!S#[Wt {k
} }03?eWk/y
} Ygg+=@].@
} ;8vB7|54.
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CountControl.java UGM:'xa<T
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/* Q`J U[nY
* CountThread.java W?E01"p
* kb~
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* Created on 2007年1月1日, 下午4:57 Oz\J+
* @qcUxu 4
* To change this template, choose Tools | Options and locate the template under 9(HGe+R4o
* the Source Creation and Management node. Right-click the template and choose EmUt/]
* Open. You can then make changes to the template in the Source Editor. ]g9SUFM
*/ .yUD\ZGJu
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package com.tot.count; 7ZAxhFC
import tot.db.DBUtils; YG*<jKcX
import java.sql.*; 6v:L8t$"
/** *wqR .n?
* xG
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* @author GBg
*/ Iw?^
public class CountControl{ +ah4 K(+3
private static long lastExecuteTime=0;//上次更新时间 3C=QWw?
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 #gWok'ZcR
/** Creates a new instance of CountThread */ rLD1Cpeb,w
public CountControl() {} D8w.r"ne
public synchronized void executeUpdate(){ ?\4kV*/Cqz
Connection conn=null; >J;J&]Olf
PreparedStatement ps=null; RjP]8tH&
try{ !}P^O(oY
conn = DBUtils.getConnection(); [m< jM[w{
conn.setAutoCommit(false); D.7cWR`Wp
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); B(71I;
for(int i=0;i<CountCache.list.size();i++){ A6_ER&9$>N
CountBean cb=(CountBean)CountCache.list.getFirst(); |I"&Z+m
CountCache.list.removeFirst(); &~.|9P/45
ps.setInt(1, cb.getCountId()); E 8W*^^z(
ps.executeUpdate();⑴ tD}{/`{_t
//ps.addBatch();⑵ f9_Pn'"I
} !T)_(}|6}
//int [] counts = ps.executeBatch();⑶ :SN? t
conn.commit(); OBlQ
}catch(Exception e){ j4@6`[n:
e.printStackTrace(); *R4=4e2#S
} finally{ 2XBHo (
try{ BH}rg,]G
if(ps!=null) { G^ <m0ew|
ps.clearParameters(); L*Ffic
ps.close(); >W/mRv&
ps=null; z/5TYv)S
} w"M!**bP
}catch(SQLException e){} %y>*9$<pXe
DBUtils.closeConnection(conn); 'dQGb-<_<
} $i8oLSRV
} It 3@
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public long getLast(){ mDwuJf8}
return lastExecuteTime; 8EiS\$O-
} pkG8g5(w
public void run(){ BB1_EdoG
long now = System.currentTimeMillis(); 0V"(}!=2a
if ((now - lastExecuteTime) > executeSep) { s&WE'
//System.out.print("lastExecuteTime:"+lastExecuteTime); Qd3ppJn
//System.out.print(" now:"+now+"\n"); 3M[d6@a
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); SJ8
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lastExecuteTime=now; lnMU5[g{
executeUpdate(); ="@f~~
} nyhHXVRH
else{ c0jTQMe4yl
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); J~@W":v
} ;6]ag< Q
} W>x.*K
} Zn|lL0b{q
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 Wa?\W&
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类写好了,下面是在JSP中如下调用。 4|jPr J
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<% |l|$Q;
CountBean cb=new CountBean(); :%fnJg(
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); |t$%kpp
CountCache.add(cb); )TNG0[
out.print(CountCache.list.size()+"<br>"); qMO(j%N5
CountControl c=new CountControl(); .UK`~17!
c.run(); iy8Ln,4z(
out.print(CountCache.list.size()+"<br>"); %&'[? LXD
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