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: B.{0,bW?
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CountBean.java h2uO+qEsu
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/* jY$|_o.4
* CountData.java ap_(/W
* q(a6@6f"kD
* Created on 2007年1月1日, 下午4:44 YZ/mTQn_D
* y"2#bq
* To change this template, choose Tools | Options and locate the template under 9$#2+G!J
* the Source Creation and Management node. Right-click the template and choose V3F2Z_VH2
* Open. You can then make changes to the template in the Source Editor. p[g!LD
*/ bumS>:
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package com.tot.count; js k<N
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/** uXK$5"
* &=_YL
* @author )[%#HT
*/ .F%RW8=Q
public class CountBean { E%/E%9-7\
private String countType; U
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int countId; RZDZ3W(;h
/** Creates a new instance of CountData */ 8FbBv"LI,g
public CountBean() {} J*$ !^\s
public void setCountType(String countTypes){ Z$6W)~;,
this.countType=countTypes; |%b' L.$4
} ?t?!)# X
public void setCountId(int countIds){ Vf O0 z5&
this.countId=countIds; D>LdDhNn,`
} #?8'Z/1)
public String getCountType(){ [.3M>,)+-
return countType; OP``g/x)
} :5C9uW#
public int getCountId(){ Lo9+#ITyx
return countId; ^Z\1z!{R
} kdgQ -UN$
} RHE< QG
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CountCache.java K<\TF+
#!Kg?BR2
/* b"{7f
* CountCache.java CX\#
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* LTFA2X&E=
* Created on 2007年1月1日, 下午5:01 gIRFqEz@o
* TLO-$>h
* To change this template, choose Tools | Options and locate the template under |A0kbC.
* the Source Creation and Management node. Right-click the template and choose 3osAWSCEL
* Open. You can then make changes to the template in the Source Editor. syBYH5
*/ /Xn I>
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package com.tot.count; se7_:0+w
import java.util.*; L3i\06M
/** dHd{9ftyF
* B#sc!eLmU&
* @author qmJFXnf
*/ u3"F7
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public class CountCache { X8?|5$Ey
public static LinkedList list=new LinkedList(); +| Cvv]Tx1
/** Creates a new instance of CountCache */ ioh_5
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public CountCache() {} 0'aZ*ozk
public static void add(CountBean cb){ *i)GoQoB
if(cb!=null){ &bA;>Lu#|o
list.add(cb); [(UQQa=+
} `Mp]iD{
} 8 rnr>Ee@
} &ec_jxF
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CountControl.java qdO^)uJJ
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/* EMJio\
* CountThread.java 1 5rE|m^
* .KK"KO5k
* Created on 2007年1月1日, 下午4:57 sveFxI
* tA'i-D&
* To change this template, choose Tools | Options and locate the template under "T#c#?
* the Source Creation and Management node. Right-click the template and choose h`Y t4-Y
* Open. You can then make changes to the template in the Source Editor. ?Yz.tg
*/ eN,m8A`/S
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package com.tot.count; hLJO\=0rJz
import tot.db.DBUtils; yh lZdF
import java.sql.*; scN}eg:5
/** Vv6xVX
* ,]20I _
* @author U3A>#EV
*/ sHh2>f@x$
public class CountControl{ gy~M]u{
private static long lastExecuteTime=0;//上次更新时间 :n>:*e@w%
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 r\_aux^z
/** Creates a new instance of CountThread */ 'VR5>r
public CountControl() {} l.b
public synchronized void executeUpdate(){ .r]n<
Connection conn=null; .hZ =8y9
PreparedStatement ps=null; =a7m^e7
try{ ;?%2dv2d
conn = DBUtils.getConnection(); )pJ}o&J
conn.setAutoCommit(false); ?MO'WB9+JR
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); `4Nc(aUr
for(int i=0;i<CountCache.list.size();i++){ `4l>%S8y:
CountBean cb=(CountBean)CountCache.list.getFirst(); %3"3OOT7
CountCache.list.removeFirst(); V}@c5)(j
ps.setInt(1, cb.getCountId()); E2%7 v
ps.executeUpdate();⑴ H$\?D+xlf
//ps.addBatch();⑵ hoSk
} QIo|t!7F
//int [] counts = ps.executeBatch();⑶ 7Zr jU{
conn.commit(); <%) :'0q&
}catch(Exception e){ HHtp.;L/
e.printStackTrace(); JEFW}M)UGv
} finally{ ed*=p
l3.
try{ =ngu*#?c4
if(ps!=null) { (|O;Ci
ps.clearParameters(); 0qJ 3@d
ps.close(); 69q8t*%O
ps=null; zM[WbB+"m
} $+*ZsIo
}catch(SQLException e){} ^k u~m5v
DBUtils.closeConnection(conn); hFQC%N.'
} 2NE/ZqREg
} -cIc&5CS
public long getLast(){ yf_<o
return lastExecuteTime; '_(oa<g
} VwtGHF'
public void run(){ cDE?X o'!
long now = System.currentTimeMillis(); '!IX;OSjH
if ((now - lastExecuteTime) > executeSep) { Fd|:7NRA<
//System.out.print("lastExecuteTime:"+lastExecuteTime); <*4=sX@
//System.out.print(" now:"+now+"\n"); M(oW;^B
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); >o'D/'>ku
lastExecuteTime=now; 5Ko"-
executeUpdate(); 9DPf2`*$
} ~V5k
else{ '[Nu;(>a
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); .%~
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} a ,W5T8
} "@`M>)*o
} 0ZPPt(7
//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 NP%ll e,l
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类写好了,下面是在JSP中如下调用。 [-Q"A
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<% D.$EvUSK<.
CountBean cb=new CountBean(); Xb|hP
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); <|.S~HLTQ
CountCache.add(cb); @LwhQ
out.print(CountCache.list.size()+"<br>"); sM~CP zMa
CountControl c=new CountControl(); +R#*eo;o7
c.run(); hRc\&+#/
out.print(CountCache.list.size()+"<br>"); Q Z9)uI
%>