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: hBRi5&%
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CountBean.java wbJBGT{sm
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/* &lU\9
* CountData.java q#AIN`H
* 9]Ue%%vM
* Created on 2007年1月1日, 下午4:44 h STcL:b
* !&Q?AS JH
* To change this template, choose Tools | Options and locate the template under "P?O1
* the Source Creation and Management node. Right-click the template and choose 1#cTk
* Open. You can then make changes to the template in the Source Editor. qE2VUEv5Y
*/ pTGGJ,
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package com.tot.count; R~iv%+
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/** J*b Je"8
* ]B;`Jf
* @author OS`jttU@
*/ l'q%bi=f
public class CountBean { sgP{A}4 W
private String countType; CR23$<FC
int countId; @Ol(:{<
/** Creates a new instance of CountData */ t O.5
public CountBean() {} Ph]b6
public void setCountType(String countTypes){ f6K.F
this.countType=countTypes; vGlVr.)
} (/<Nh7C1c
public void setCountId(int countIds){ 6QA`u*
this.countId=countIds; T0dD:s N
} ~n@rX=Y)]0
public String getCountType(){ a(6h`GHo
return countType; @*<0:Q|m
} D|Q7dIZm
public int getCountId(){ al}J^MJ
return countId; L!*+:L
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} ?Xvy0/s5
} #S9J9k
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CountCache.java XQn1B3k+
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/* J;Z2<x/H
* CountCache.java O<Q8%Az
* &kzysv-_
* Created on 2007年1月1日, 下午5:01 66F?exr
* 5b/ ~]v
* To change this template, choose Tools | Options and locate the template under m-azd~r[
* the Source Creation and Management node. Right-click the template and choose ]w>o=<?b
* Open. You can then make changes to the template in the Source Editor. ]i(/T$?~
*/ 4 @{?4k-cq
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package com.tot.count; W;=Ae~
import java.util.*; /;(ji?wN
/** nl
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* v.<mrI#?
* @author hT 1JEu
*/ FfM^2`xP
public class CountCache { MZ$uWm`/
public static LinkedList list=new LinkedList(); 5C1EdQ4S0
/** Creates a new instance of CountCache */ Wgh@X B
public CountCache() {} WtZI1`\qe
public static void add(CountBean cb){ 1N(1h
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if(cb!=null){ 5z0VMt
list.add(cb); G`n
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} -O\i^?lD;
} TyIjDG6tM
} Rs5 lL-I
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CountControl.java Z[IM\# "
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/* Y&yfm/R u
* CountThread.java M\4`S&
* @~$"&B
* Created on 2007年1月1日, 下午4:57 pml33^*<U
* g=4^u*
* To change this template, choose Tools | Options and locate the template under Sp X;nH-D
* the Source Creation and Management node. Right-click the template and choose aA#79LS
* Open. You can then make changes to the template in the Source Editor. ~5&4s
*/ AcuF0KWw/
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package com.tot.count; V>T?'GbS
import tot.db.DBUtils; gm)Uyr$
import java.sql.*; nI]EfHU
/** <7Pp98si,u
* \fTQNF
* @author ;_"|#
*/ ? nW>'z
public class CountControl{ T#-;>@a}
private static long lastExecuteTime=0;//上次更新时间 la+Cra&xL
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 mF\!~ag|
/** Creates a new instance of CountThread */ 6qZ\^ U
public CountControl() {} A811VL^
public synchronized void executeUpdate(){ ErNYiYLi]
Connection conn=null; Oq.ss!/z
PreparedStatement ps=null; 4{kH;~
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try{ ~i;{+j6Ho!
conn = DBUtils.getConnection(); t([}a~1}
conn.setAutoCommit(false); <r:AJ;
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); B%;MGb o
for(int i=0;i<CountCache.list.size();i++){ u5A?; a
CountBean cb=(CountBean)CountCache.list.getFirst(); `Fn"QL-
CountCache.list.removeFirst(); b`-|7<s
ps.setInt(1, cb.getCountId()); @5nFa~*K%
ps.executeUpdate();⑴ @/<UhnI
//ps.addBatch();⑵ *
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} %nY\"
//int [] counts = ps.executeBatch();⑶ Pt"H_SW~k
conn.commit(); 7m-%
}catch(Exception e){ _aPAn|.
e.printStackTrace(); =lJ
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} finally{ "wOfs$w%s
try{ 4`#Q
if(ps!=null) { )k,n}
ps.clearParameters(); DSz[,AaR]
ps.close(); 7tcadXk0
ps=null; tsc`u>
} >l&]Ho
}catch(SQLException e){} kh0cJE\_^
DBUtils.closeConnection(conn); 4uIYX
} EpAgKzVpJ
} Z71m(//*}
public long getLast(){ D|9+:Y
return lastExecuteTime; *(Dmd$|0|
} u)0I$Tc"
public void run(){ _h!.gZB3
long now = System.currentTimeMillis(); 7l69SQo]?
if ((now - lastExecuteTime) > executeSep) { 3{3@>8{w
//System.out.print("lastExecuteTime:"+lastExecuteTime); g Y~r{
//System.out.print(" now:"+now+"\n"); GjhTF|
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); !CYC7HeF
lastExecuteTime=now; 0M HiW=
executeUpdate(); Ax=HDW}
} T-%=tY+-
else{ Eu?z!
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); X@`a_XAfd
} (P)G|2=
} Q|AZv>'!
}
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//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 >u$8Z
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类写好了,下面是在JSP中如下调用。 -)}s{[]d6m
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<% sP(+Z^/
CountBean cb=new CountBean(); 5Ml=<^
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); Z0Z6aZeb
CountCache.add(cb); )]1hN;Nz
out.print(CountCache.list.size()+"<br>"); 6CBk=)qH
CountControl c=new CountControl(); dDPQDIx
c.run(); _B^zm-}8|B
out.print(CountCache.list.size()+"<br>"); ~18a&T:
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