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: !HPye@Ua
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CountBean.java U#=5HzE
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/* ! >l)*jN8
* CountData.java [c_o.`S_\
* Iurb?
* Created on 2007年1月1日, 下午4:44 F.[E;gOTo
* c. ;}e:)s
* To change this template, choose Tools | Options and locate the template under qkk!1W
* the Source Creation and Management node. Right-click the template and choose ?z$^4u3
* Open. You can then make changes to the template in the Source Editor. IGC:zZ~z
*/ O${B)C,
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package com.tot.count; W+&<C#1|]
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/** 9yt)9f
* x%d\}%]
* @author XFv) ]_G
*/ s}5,<|DL
public class CountBean { e0; KmQjG
private String countType; SZ'2/#R>
int countId; [@LA<Z_
/** Creates a new instance of CountData */ 0V_dg |.
public CountBean() {} 6mAaFDI,R
public void setCountType(String countTypes){ +P5\N,,7R
this.countType=countTypes; >/5'0n_R
} 6Yu&'[?H$
public void setCountId(int countIds){ -0o1iU7
this.countId=countIds; #'&&&_Hu3
} eNEMyv5{w4
public String getCountType(){ 1U(P0$C
return countType; 8+yCP_Y4
} 1x8zub B
public int getCountId(){ "0ZBPp1q
return countId; -h?ed'e/zz
} 6b6rM%B.oD
} EFqYEDXW
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CountCache.java 8'}D/4MUr
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/* > q!:*
* CountCache.java n#Y=y#
* EO:
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* Created on 2007年1月1日, 下午5:01 z +NwGVk3
* o$%I{}9x
* To change this template, choose Tools | Options and locate the template under 9yrSCDu00
* the Source Creation and Management node. Right-click the template and choose cU
* Open. You can then make changes to the template in the Source Editor. a\@k5?
*/ '1r<g\l
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package com.tot.count; lCAD $Ia~
import java.util.*; @7j$$
/** sJ
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* @author X]T&kdQ6q
*/ s`63
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public class CountCache { bAVlL&^@|
public static LinkedList list=new LinkedList(); b Y^K)0+^s
/** Creates a new instance of CountCache */ (G<fvl!~
public CountCache() {} 1@"os[9
public static void add(CountBean cb){ alV{| Vf[6
if(cb!=null){
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list.add(cb); Fk*C8
} cq#=Vb
} &]_2tN=S$
} lv=rL
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CountControl.java 7(W"NF{r
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/* &o]ic(74c?
* CountThread.java &s>E~M0+J
* ?Tr\r1s]
* Created on 2007年1月1日, 下午4:57 }VDJ
* 5xIOi(3`Q
* To change this template, choose Tools | Options and locate the template under 'Xb?vOU
* the Source Creation and Management node. Right-click the template and choose N}rc3d#
* Open. You can then make changes to the template in the Source Editor. !bGMVw6_
*/ __OH
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package com.tot.count; y|Vwy4tK9
import tot.db.DBUtils; PC55A1(T
import java.sql.*; =`W#R
/** =f\BAi
* EWNm }C9
* @author p/WE[8U
*/ N*NGC!p`N
public class CountControl{ yZyB.wT
private static long lastExecuteTime=0;//上次更新时间 oH>G3n|U^
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 _p^&]eQ+k#
/** Creates a new instance of CountThread */ agUdPl$e\
public CountControl() {} .jK,6't^
public synchronized void executeUpdate(){ %SKJ#b
Connection conn=null; og)f?4
PreparedStatement ps=null; /4wPMAlb
try{ CjT]!D)s
conn = DBUtils.getConnection(); 3^-yw`
conn.setAutoCommit(false); RJa1pYK
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); qw35LyL
for(int i=0;i<CountCache.list.size();i++){ tuIQiWHbM
CountBean cb=(CountBean)CountCache.list.getFirst(); <#>{7" }
CountCache.list.removeFirst(); >uy(N
ps.setInt(1, cb.getCountId()); ;/s##7qf
ps.executeUpdate();⑴ &wea]./B
//ps.addBatch();⑵ Q35jJQ$<`
} #y>q)Ph
//int [] counts = ps.executeBatch();⑶ gWLhO|y
conn.commit(); Dxp.b$0t
}catch(Exception e){ *h)|Ks
e.printStackTrace(); s.j6"
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} finally{ ywkyxt
try{ %XiF7<A&
if(ps!=null) { Zv^n
ps.clearParameters(); =Yt)b/0b9
ps.close(); xI(t!aYp
ps=null; >yr1wVS
} w3E#v&"=Y
}catch(SQLException e){} -![>aqWmj1
DBUtils.closeConnection(conn); </-aG[Fi
} a"bael
} E*G{V j
public long getLast(){ ]3&BLq
return lastExecuteTime; /P
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} fj:q_P67o
public void run(){ ]!'9Y}9a
long now = System.currentTimeMillis(); 6Om-[^
if ((now - lastExecuteTime) > executeSep) { Rl3KE)<
//System.out.print("lastExecuteTime:"+lastExecuteTime); e@0wF59
//System.out.print(" now:"+now+"\n"); [rPW@|^5
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ])~*)I~Y
lastExecuteTime=now; M?$-u
executeUpdate(); %F&j B
} 7GK| A{r
else{ 1 ,D2][
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); sd8o&6
} ,fET.s^|U
} .D4D!!
} #|$i H kVY
//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 `r>WVPS|
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类写好了,下面是在JSP中如下调用。 kmov(V
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<% X[Y!=e4z
CountBean cb=new CountBean(); sSD(mO<(
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); S8"X7\d{
CountCache.add(cb); >%[(C*Cks
out.print(CountCache.list.size()+"<br>"); C(,s_Ks
CountControl c=new CountControl(); g4Hq<W"
c.run(); &nz1[,
out.print(CountCache.list.size()+"<br>"); },i?3dSvl
%>