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: i`vy<Dvpz
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CountBean.java l2dj GZk
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/* (mI590`f
* CountData.java ^mC,Z+!
* tc\ZYCFr
* Created on 2007年1月1日, 下午4:44 FDGG$z?>m
* n^5Q
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* To change this template, choose Tools | Options and locate the template under -F3~X R
* the Source Creation and Management node. Right-click the template and choose Zv-1*hhHf
* Open. You can then make changes to the template in the Source Editor. 0E
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*/ &0%B3
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package com.tot.count; ryA+Lli.
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/** -O-?hsV)y
* g4 +Hq *
* @author &uBfsa$
*/ B8.}9
public class CountBean { Iu >4+6
private String countType; co^h2b
int countId; ,7k1n{C)
/** Creates a new instance of CountData */ aU[!*n 4Ux
public CountBean() {} =]pEvj9o
public void setCountType(String countTypes){ Z ZCm438
this.countType=countTypes; 'Yc^9;C(
} qZ@d:u
public void setCountId(int countIds){ mieyL9*n7
this.countId=countIds; hJir_=
} ssoE ,6kS
public String getCountType(){ oK4xRv8Hd
return countType; ZBN,%P!P0
} +Kg }R5+
public int getCountId(){ BD86t[${W
return countId; asLrXGGyT
} `P*BW,P'T
} |90X_6(
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CountCache.java [/ertB
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/* IXm[c@5l
* CountCache.java oj)(.X<8N
* H~>8q~o]
* Created on 2007年1月1日, 下午5:01 9nFWJn
* KH=3HN}
* To change this template, choose Tools | Options and locate the template under DxpJP,wY3
* the Source Creation and Management node. Right-click the template and choose Y3(I;~$!
* Open. You can then make changes to the template in the Source Editor. Tm7LaM
*/ MEp{v|1
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package com.tot.count;
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import java.util.*; S{f,EBE
/** }:;UnE}
* Hr!$mf)h
* @author -Wh 2hWg+
*/ G#6Z@|kVw
public class CountCache { KT >Y^
public static LinkedList list=new LinkedList(); ?d{O'&|:
/** Creates a new instance of CountCache */ #5'@at'1
public CountCache() {} \+l_H4\`K
public static void add(CountBean cb){ iDhC_F|
if(cb!=null){ DQc\[Gq&
list.add(cb); kp}[nehF
} Y5;afU='
} }&2,!;"">3
} #Er"i
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CountControl.java 6-J}ZfGj
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/* 6%>'n?
* CountThread.java 6?C';1
* *vEj\
* Created on 2007年1月1日, 下午4:57 tns8B
* V|}9bNF
* To change this template, choose Tools | Options and locate the template under J2!
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* the Source Creation and Management node. Right-click the template and choose iXL^[/}&?M
* Open. You can then make changes to the template in the Source Editor. U?5lqq
*/ bX(/2_l
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package com.tot.count; .cw)Y#;IG
import tot.db.DBUtils; hN]l
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import java.sql.*; "+wkruC
/** S?C.:
* iF837ng5
* @author h{$k%YJ?
*/ 0( A ?&
public class CountControl{ TJZ~Rpq
private static long lastExecuteTime=0;//上次更新时间 ]*lZFP~
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 [6_.Y*}N
/** Creates a new instance of CountThread */ Md~._@`|K
public CountControl() {} YhfQpe
public synchronized void executeUpdate(){ [{[m)Z^
Connection conn=null; /`DKX }
PreparedStatement ps=null; 1@h8.ym<"
try{ 2/uZ2N|S
conn = DBUtils.getConnection(); K9p<PLy+
conn.setAutoCommit(false); -zqpjxU:
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); +'MO$&6
for(int i=0;i<CountCache.list.size();i++){ Tcc83_Iq
CountBean cb=(CountBean)CountCache.list.getFirst(); BnGoB`n
CountCache.list.removeFirst(); ]vn*eqd
ps.setInt(1, cb.getCountId()); SE6(3f$
ps.executeUpdate();⑴ 1TR+p? "
//ps.addBatch();⑵ /~f[>#
} d
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//int [] counts = ps.executeBatch();⑶ YZSQOLN{
conn.commit(); Ldv,(ZV,<
}catch(Exception e){ o$+R
e.printStackTrace(); -1v9
} finally{ WG,1%=M@
try{ ^,AE;ZT7
if(ps!=null) { b7~Jl+m
ps.clearParameters(); Iz. h
ps.close(); cg17e
ps=null; -$0}rfX
} I}0? d
}catch(SQLException e){} !k*B-@F
DBUtils.closeConnection(conn); _5~|z$GW
} K@g
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} ZeU){CB
public long getLast(){ SOM? 0.
return lastExecuteTime; T#E$sZ
} YGLq~A
public void run(){ v~T)g"_|
long now = System.currentTimeMillis(); / Wjc\n$'
if ((now - lastExecuteTime) > executeSep) { <2&qIvHL
//System.out.print("lastExecuteTime:"+lastExecuteTime); &B[*L+-E
//System.out.print(" now:"+now+"\n"); DrV[1Z
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); <jF&+[*iT
lastExecuteTime=now; S Z/yijf
executeUpdate(); bPP@
} jQ%1lQ#R)
else{ CrL9|78
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ]BbV\#
} `Ds=a`^b
} mI4GBp
} hZL!%sL7
//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 lnyq%T[^
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类写好了,下面是在JSP中如下调用。 e@0|fB%2
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<% O TlqJ
CountBean cb=new CountBean(); oST)E5X;7
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); eLORG(;h4
CountCache.add(cb); 7 =}tJ
out.print(CountCache.list.size()+"<br>"); r0lI&25w
CountControl c=new CountControl(); Tgtym"=xd
c.run(); DzE^FY
out.print(CountCache.list.size()+"<br>"); Y<VX.S2kf
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