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: >}`1'su
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CountBean.java `>HthK
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/* t"m`P1
* CountData.java ?q8g<-?
* R(#;yn
* Created on 2007年1月1日, 下午4:44 %x)U8
* +mel0ZStS
* To change this template, choose Tools | Options and locate the template under R}YryzV5
* the Source Creation and Management node. Right-click the template and choose kxiyF$
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* Open. You can then make changes to the template in the Source Editor. (W6\%H2u
*/ H0:6zSsc=|
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package com.tot.count; Gf$>!zXr
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/** yD'h5)yu
* T</gWW
* @author cnO4NUDv
*/ HCZ%DBU96
public class CountBean { -&^( T
private String countType; {nWtNyJpS
int countId; lY8Qy2k|
/** Creates a new instance of CountData */
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public CountBean() {} w'j]Y%
public void setCountType(String countTypes){ [?(W7
this.countType=countTypes; ziip*<a!_
} AZP>\Dq
public void setCountId(int countIds){ P =Gb
this.countId=countIds; z?g4^0e
} ^E,UcK;
public String getCountType(){ "s^@PzQpN
return countType; ;^SgV
} Y\F H4}\S
public int getCountId(){ ijSYQ
return countId; Y'":OW#oN
} DdW8~yI&
} IWd*"\L
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CountCache.java M0\[hps~X
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/* ^ @cX0_
* CountCache.java f)fw87UPc
* :H k4i%hGk
* Created on 2007年1月1日, 下午5:01 66;O 3g'
* M& L0n%,y5
* To change this template, choose Tools | Options and locate the template under }tq9 /\
* the Source Creation and Management node. Right-click the template and choose UYLI>XSd
* Open. You can then make changes to the template in the Source Editor. _)\,6| #
*/ {x$#5PW
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package com.tot.count; 2,`mNjHh
import java.util.*; ;hp; Rd
/** 7hE=+V8
* cMKh+r
* @author LB0=V0|
*/ 09i[2n;O
public class CountCache { 7guxkN#
public static LinkedList list=new LinkedList(); iIRigW
/** Creates a new instance of CountCache */ 4H'&5
public CountCache() {} dRC+|^rSC
public static void add(CountBean cb){ $*> _0{<
if(cb!=null){ KL{uhb0f
list.add(cb); &WS%sE{p_
} lsf?R'1
} eu/Sp3@v
} -I<`!kH*
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CountControl.java l^Z~^.{y
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/* 7qp|Msf},
* CountThread.java )f|6=x4
* 3_:k12%p
* Created on 2007年1月1日, 下午4:57 }7^*%$
* jR:Fih-}
* To change this template, choose Tools | Options and locate the template under (CwaOm{g
* the Source Creation and Management node. Right-click the template and choose an@Ue7
* Open. You can then make changes to the template in the Source Editor. 4\iQ%fb
*/ \|s/_35(
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package com.tot.count; HRh".!lxy
import tot.db.DBUtils; ;#
import java.sql.*; B 8,{jwB
/** ObnB6ShKi
* \`&fr+x
* @author b9jm=U
*/ wVX0!y6
public class CountControl{ ^|z>NV5>
private static long lastExecuteTime=0;//上次更新时间 v.J#d>tvf
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ~KvCb3~X
/** Creates a new instance of CountThread */ 1Zzw|@#>o
public CountControl() {} X[}%iEWzT
public synchronized void executeUpdate(){ YTA&G
Connection conn=null; "Y6mM_flq
PreparedStatement ps=null; dDn:^)
try{ 4G2V{(@QiZ
conn = DBUtils.getConnection(); *a4eL [
conn.setAutoCommit(false); U^I'X7`r
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); X+jSB,
for(int i=0;i<CountCache.list.size();i++){ Vy VC#AK,
CountBean cb=(CountBean)CountCache.list.getFirst(); /PlsF
CountCache.list.removeFirst(); xR3A4m
ps.setInt(1, cb.getCountId()); nXjUTSGa)
ps.executeUpdate();⑴ `MS=/x E
//ps.addBatch();⑵ HF:PF"|3
} Qw+">
//int [] counts = ps.executeBatch();⑶ J.(_c'
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conn.commit(); 4)z](e$
}catch(Exception e){ Q2uE_w`B
e.printStackTrace(); ?*0kQo'
} finally{ 7y3; F7V
try{ *!kg@ _0K
if(ps!=null) { =T`-h"E~@
ps.clearParameters(); *bK@ A2`
ps.close(); kzT'
ps=null; *G4;
} 0v?,:]A0E
}catch(SQLException e){} V8/o@I{U[
DBUtils.closeConnection(conn); Z^3Risi
} bC|~N0b
} ?CC6/bE-{
public long getLast(){ TMrmyvv
return lastExecuteTime; '}=M~
} 5s9~rm
public void run(){ qZ.\GHS
long now = System.currentTimeMillis(); {lA@I*_lj
if ((now - lastExecuteTime) > executeSep) { mdd~B2"el
//System.out.print("lastExecuteTime:"+lastExecuteTime); JB7]51WH@
//System.out.print(" now:"+now+"\n"); &}ow-u9c3
// System.out.print(" sep="+(now - lastExecuteTime)+"\n");
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lastExecuteTime=now; Nx"?'-3Hm
executeUpdate(); GupKM%kM
} MvCBgLN
else{ -p }]r
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); '1+ Bgf
} (46)v'?
} bPEAG=l "-
} Fei$94a
//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 ,>Q,0bVhH0
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类写好了,下面是在JSP中如下调用。 U+z&jdnhDR
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<% 2= _.K(
CountBean cb=new CountBean(); #"|Ey6&
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); cVMTT]cj1
CountCache.add(cb); 3
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out.print(CountCache.list.size()+"<br>"); jB;+tDC!Co
CountControl c=new CountControl(); Hs9uDGWp
c.run(); 7%tn+
out.print(CountCache.list.size()+"<br>"); &fcRVku
%>