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: mBwM=LAZ
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CountBean.java S3?Bl'
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/* ?DGe}?pX
* CountData.java @sr~&YhA
* ^@V;`jsll
* Created on 2007年1月1日, 下午4:44 o^efeI
* gTM*td(~^
* To change this template, choose Tools | Options and locate the template under [
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* the Source Creation and Management node. Right-click the template and choose yv;KKQ
* Open. You can then make changes to the template in the Source Editor. mhNX05D
*/ 5V $H?MW>
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package com.tot.count; n%S%a>IQj
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/** xCQLfXK7
* *2T"lpl
* @author YAdk3y~pL
*/ CyV2=o!F w
public class CountBean { & FpoMW
private String countType; /Kd9UQU
int countId; i8h^~d2"
/** Creates a new instance of CountData */ uGc0Lv4i/
public CountBean() {} 1PN!1= F}
public void setCountType(String countTypes){ ke)}JU^"
this.countType=countTypes; @zCp/fo3
} d :vuRK4+
public void setCountId(int countIds){ u\AL`'v
this.countId=countIds; 7WMF8(j5
} Oxp!G7qfo
public String getCountType(){ "-
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return countType; TOb(
} sd5)We
public int getCountId(){ ]3\%i2NM
return countId; `x:O&2
} h(/& ;\Cr
} FKH_o
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CountCache.java ;Tec)Fl
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/* *-';ycOvr
* CountCache.java "?M)2,:A
* ~( ;HkT
* Created on 2007年1月1日, 下午5:01 |V&E q>G
* -`A+Qp)
* To change this template, choose Tools | Options and locate the template under 8yC/:_ML
* the Source Creation and Management node. Right-click the template and choose hDf!l$e.
* Open. You can then make changes to the template in the Source Editor. Qx_]oz]NY
*/ XOoz.GSQ
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package com.tot.count; .Cu0G1
import java.util.*; Gspb\HJ^
/** pt%*Y.)az
* j0~dJ#
* @author )tv~N7
*/ [y&uc
public class CountCache {
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public static LinkedList list=new LinkedList(); xdgbs-a)
/** Creates a new instance of CountCache */ '!"rE1e
public CountCache() {} 2w;Cw~<=d
public static void add(CountBean cb){ H1d2WNr[
if(cb!=null){ *AG01# ZF
list.add(cb); J(Fk@{!F.*
} FvXpqlp
} hEA;5-m
} {rzvZ0-j}
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CountControl.java
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/* fP/;t61Z
* CountThread.java ;3\'}2^|l
* 8xt8kf*k
* Created on 2007年1月1日, 下午4:57 4jw q$G
* _/NPXDL
* To change this template, choose Tools | Options and locate the template under c{3P|O&.
* the Source Creation and Management node. Right-click the template and choose U.Fs9F4M #
* Open. You can then make changes to the template in the Source Editor. 0C4Os p
*/ AbL(F#{
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package com.tot.count; L>n^Q:M
import tot.db.DBUtils; %RIlu[J
import java.sql.*; Rxq4Diq5k
/** gbu*6&j9
* q\/xx`L
* @author fC+tu>=
*/ +fN2%aC
public class CountControl{ ge ]Z5E(1
private static long lastExecuteTime=0;//上次更新时间 tP89gN^PA|
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 }\QXPU{UVd
/** Creates a new instance of CountThread */ -U{!'e8YiN
public CountControl() {} ETm:KbS
public synchronized void executeUpdate(){ ~g}blv0q+B
Connection conn=null; lXRB"z
PreparedStatement ps=null; MM*9Q`cB
try{ E
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conn = DBUtils.getConnection(); T>irW(
conn.setAutoCommit(false); cv_t2m
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); : cPV08i
for(int i=0;i<CountCache.list.size();i++){ fS3%
CountBean cb=(CountBean)CountCache.list.getFirst(); XCT3:db
CountCache.list.removeFirst(); %3yrX>Js
ps.setInt(1, cb.getCountId()); }O\g<ke:u
ps.executeUpdate();⑴ nT7]PhJ
//ps.addBatch();⑵ j>3Fwg9V
} bsc#Oq]
//int [] counts = ps.executeBatch();⑶ [W99}bi$
conn.commit(); g,B@*2Uj
}catch(Exception e){ d*$x|B|V
e.printStackTrace(); @QDUz>_y
} finally{ SC--jhDZ
try{ >#y1(\e
if(ps!=null) { W~5gTiBZ]
ps.clearParameters(); ab[V->>%
ps.close(); s$~H{za
ps=null; `)NTJc$):
} CdKs+x&tZ
}catch(SQLException e){} TA+#{q+a
DBUtils.closeConnection(conn); "?6R"Vk?:
} 3}B-n!|*
} Li+|%a
public long getLast(){ 0zk054F'
return lastExecuteTime; .*?)L3n+t
} hVdGxT]6
public void run(){ }tJMnq/m($
long now = System.currentTimeMillis(); orFB*{/Z
if ((now - lastExecuteTime) > executeSep) { Z
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//System.out.print("lastExecuteTime:"+lastExecuteTime); Ch]q:o4
//System.out.print(" now:"+now+"\n"); 1pqYB]*u_
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); X*a7`aL
lastExecuteTime=now; $#_^uWN-M
executeUpdate(); iZ0.rcQj'o
} KP!7hJhw
else{ nyZ?m
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 'i;ofJ[.c
} o3`0x9{
} I#xhmsF
}
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//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 OkphbAX
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类写好了,下面是在JSP中如下调用。 Q;@w\_OR
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<% xEB4oQ5
CountBean cb=new CountBean(); v%QCp
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); <#~n+,
CountCache.add(cb);
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out.print(CountCache.list.size()+"<br>"); Lve$H(GHT
CountControl c=new CountControl(); BbI),iP
c.run(); S;BMM8U
out.print(CountCache.list.size()+"<br>"); nb@<UbabW}
%>