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: (ROY?5
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CountBean.java H4&lb}
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/* gG(fQ
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* CountData.java [\v}Ul
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* Created on 2007年1月1日, 下午4:44 uxvqMgR
* +0nJ
* To change this template, choose Tools | Options and locate the template under dMv=gdY
* the Source Creation and Management node. Right-click the template and choose nrub*BuA
* Open. You can then make changes to the template in the Source Editor. 4;yKOQD|
*/ JfLqtXF[&"
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package com.tot.count; eD?tLj
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/** 8]/bK5`
* _E@2ZnD2
* @author hK L4cpK4
*/ f!Y?S
public class CountBean { 5YE'L.
private String countType; DgId_\Ze
int countId; sBvzAVBL
/** Creates a new instance of CountData */ Ezc?#<+7
public CountBean() {} tE<H|_{L
public void setCountType(String countTypes){ K*K,}W&}
this.countType=countTypes; D#cyOrzy
} RzE_K'M
public void setCountId(int countIds){ saBVgSd
this.countId=countIds; ]%@M>?Ywc
} 4i)1'{e
public String getCountType(){ %[Wh [zZy
return countType; \XCe22x]
} EE&K0<?T|:
public int getCountId(){ 1"MhGNynB>
return countId; N} G[7Rp8l
} %*A0# F
} .sha&
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CountCache.java .o(fe\KHf
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/* =_JjmTy;a
* CountCache.java mqD}BOif
* 2=,lcWr
* Created on 2007年1月1日, 下午5:01 5Dm.K?l;
* >%}C^gu)
* To change this template, choose Tools | Options and locate the template under z+0I#kM"1
* the Source Creation and Management node. Right-click the template and choose 3]}D`Qs6
* Open. You can then make changes to the template in the Source Editor. %?0:vn
*/ @vC4[:"pD}
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package com.tot.count; Ns>-
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import java.util.*; +~m46eI
/** XixL R
* ?uzRhC_)!
* @author Elcj tYu4
*/ s4X>.ToMC
public class CountCache { k:t]s_`<
public static LinkedList list=new LinkedList(); e'6/`Evqz
/** Creates a new instance of CountCache */ aH)}/n
public CountCache() {} JU1~e@/'%
public static void add(CountBean cb){ Z]>O+
if(cb!=null){ |mxDjgq
list.add(cb); !JHL\M>A5
} Ra)3+M!x
} Y2N>HK0
} ?PuBa`zDE
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CountControl.java \=VtHu92=
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/* ^me-[
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* CountThread.java u%&`}g
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* Created on 2007年1月1日, 下午4:57 `06;
* g0xuxK;9c
* To change this template, choose Tools | Options and locate the template under kj#?whK6~
* the Source Creation and Management node. Right-click the template and choose {j.bC@hWw
* Open. You can then make changes to the template in the Source Editor. Ec3}_`
*/ |7'df &CA
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package com.tot.count; -u6bAQ
import tot.db.DBUtils; \:%(q/v"X
import java.sql.*; T,,WoPU8t
/** yr)G]K[/
* %P;lv*v.
* @author 7Haa;2
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*/ F&4rO\aC"/
public class CountControl{ >:74%D0UF
private static long lastExecuteTime=0;//上次更新时间 [owWiN4`s
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 Ci@o|Y }tP
/** Creates a new instance of CountThread */ MK%9:wZ
public CountControl() {} ~qiJR`Jj
public synchronized void executeUpdate(){ }*M6x;t
Connection conn=null; $t$ShT)
PreparedStatement ps=null; y;35WtDVb
try{ j+i\bks
conn = DBUtils.getConnection(); G,&<<2{(f;
conn.setAutoCommit(false); 7-bd9uVK
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); F&!6jv
for(int i=0;i<CountCache.list.size();i++){ B~1_ 28\
CountBean cb=(CountBean)CountCache.list.getFirst(); H4WP~(__
CountCache.list.removeFirst(); Q:2>}QgX}
ps.setInt(1, cb.getCountId()); / C:Y94B-z
ps.executeUpdate();⑴ u
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//ps.addBatch();⑵ wT6"U$cV
} pj\u9
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//int [] counts = ps.executeBatch();⑶ du<tGsy
conn.commit(); [g7L&`f9
}catch(Exception e){ g;H=6JeG/
e.printStackTrace(); Lu?C-$a C
} finally{ .p<:II:6
try{ nD_GL
if(ps!=null) { |U:k,YH
ps.clearParameters(); r<9Iof4
ps.close(); j@n)kPo,1
ps=null; k$ 4y9{
} @:oXN]+
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}catch(SQLException e){} Ot4 Z{mA
DBUtils.closeConnection(conn); b)6D_Az7c
} %R}qg6dL
} , Rk9N
public long getLast(){ ax"+0L{
return lastExecuteTime; ^=GC3%
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} ui<N[
public void run(){ |UkR'Ma
long now = System.currentTimeMillis(); Gt\lFQ
if ((now - lastExecuteTime) > executeSep) { wg9t)1k{e
//System.out.print("lastExecuteTime:"+lastExecuteTime); *D'22TO[[!
//System.out.print(" now:"+now+"\n"); 9&$y}Y
// System.out.print(" sep="+(now - lastExecuteTime)+"\n");
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lastExecuteTime=now; 7o7)0l9!
executeUpdate(); ew>XrT=Zm
} ()Y~Q(5ji
else{ z 9vInf@M
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 3U<cWl@
} e),q0%5
} ahJ`T*)HY
} J9\Cm!H
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 2]z8:a
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类写好了,下面是在JSP中如下调用。 ,1y@Z 5wy
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<% Yk'XGr)
CountBean cb=new CountBean(); y`L>wq,KU
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 8EZ$g<}
CountCache.add(cb);
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out.print(CountCache.list.size()+"<br>"); Xe3U`P7(
CountControl c=new CountControl(); R4[N:~Z$|
c.run();
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out.print(CountCache.list.size()+"<br>"); S(k3 `;K
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