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: _a1x\,R|DB
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CountBean.java 9-MUX^?u
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/* fkac_X$7
* CountData.java *QH28%^
* e=.]F*:J
* Created on 2007年1月1日, 下午4:44 /~3r;M
* thhwN
A
* To change this template, choose Tools | Options and locate the template under 8YbE`32
* the Source Creation and Management node. Right-click the template and choose EAM5{Nc
* Open. You can then make changes to the template in the Source Editor. fk&8]tK4
*/ MdW]MW{
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package com.tot.count; <_7*67{
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/** *c2YRbU(
* o_~eg8
* @author |j7,Mu+
*/ A,a.8!*}vd
public class CountBean { UeRj< \"Q
private String countType; P?k0zwOlBl
int countId; >Z5gSs0
/** Creates a new instance of CountData */ "yS _s
public CountBean() {} .4E&/w+
public void setCountType(String countTypes){ adR)Uq9
this.countType=countTypes; R#I0|;q4|p
} x U4 +|d
public void setCountId(int countIds){ jEZMUqGY!
this.countId=countIds; ojanBg
} Rx}$0c0
public String getCountType(){ B\o Mn
return countType; H["`Mn7j2
} ,Pdf,2
public int getCountId(){ C@'h<[v`1v
return countId; XMxSQ B1
} N$U$5;r~`
} 6;ixa
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CountCache.java T[g[&K1Y
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/* 24z< gO
* CountCache.java zdYy^8V|z
* kH
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* Created on 2007年1月1日, 下午5:01 ;6>2"{NW
* \nPEyw,U
* To change this template, choose Tools | Options and locate the template under H}hiT/+$
* the Source Creation and Management node. Right-click the template and choose ~?K ~L~f5
* Open. You can then make changes to the template in the Source Editor. ,[P{HrHx
*/ V3^&oe%
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package com.tot.count; YoBDvV":@
import java.util.*; s~5[![1
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/** I|^;B8[
* Z{]0jhUyNh
* @author qVH1}9_
*/ <
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public class CountCache { \1D<!k\S
public static LinkedList list=new LinkedList(); ahJ`$U4n
/** Creates a new instance of CountCache */ b4[bL2J$h1
public CountCache() {} `erV$( M
public static void add(CountBean cb){ l1BtI_7p
if(cb!=null){ '"SEw
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list.add(cb); :bwjJ}F
} `4=^cyt+
} ,-8"R`UI8
} >0ow7Uw;
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CountControl.java S4Y&
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/* (k5We!4[1
* CountThread.java $4h 5rC g0
* oX30VfT
* Created on 2007年1月1日, 下午4:57 }`%*W`9b
* C~2F9Pg
* To change this template, choose Tools | Options and locate the template under |H;F7Y_
* the Source Creation and Management node. Right-click the template and choose %4et&zRC
* Open. You can then make changes to the template in the Source Editor. ILEz;D{]
*/ p<2L.\6"
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package com.tot.count; -GhP9; d
import tot.db.DBUtils; "{@A5A
import java.sql.*; zzTfYf)
/** [j=yMP38!:
* +6HVhoxU#
* @author ?!A7rb/tj
*/ Ve}(s?hU5
public class CountControl{
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private static long lastExecuteTime=0;//上次更新时间 hYPl&^
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 Dfg2`l
/** Creates a new instance of CountThread */ oHd FMD@
public CountControl() {} \^L`7cBL
public synchronized void executeUpdate(){ e!N:,`R
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Connection conn=null; *|%@6I(
PreparedStatement ps=null; $q6BP'7
try{ /uPcXq:L~
conn = DBUtils.getConnection(); R!\_rc1/
conn.setAutoCommit(false); {o_X`rgrL
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); Cl;oi}L
for(int i=0;i<CountCache.list.size();i++){ ~zCEpU|@N
CountBean cb=(CountBean)CountCache.list.getFirst(); q rJ`1
CountCache.list.removeFirst(); _}lZ,L(w
ps.setInt(1, cb.getCountId()); :ubV };
ps.executeUpdate();⑴ n0r+A^]
//ps.addBatch();⑵ 5D\f8L
} 4|buk]9
//int [] counts = ps.executeBatch();⑶ {> eXR?s/
conn.commit(); @$S+ Ne[<
}catch(Exception e){ XG{{ 2f
e.printStackTrace(); K2M~-S3
} finally{ 7Ri46Tkt
try{ QdT}wkX
if(ps!=null) { mHV%I@`Y6
ps.clearParameters(); nKPYOY8^
ps.close(); ^U
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ps=null; 8ja$g,
} sF!($k;!
}catch(SQLException e){} K0-ypU*P
DBUtils.closeConnection(conn); sy:[T T!w
} iHeN9 cl
} -I*^-+>H
public long getLast(){ d"}k!
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return lastExecuteTime; Vq2y4D?
} -~s!73pDY
public void run(){ #pP[xE"Y
long now = System.currentTimeMillis(); 7mI:|G
if ((now - lastExecuteTime) > executeSep) { /Y9>8XSc
//System.out.print("lastExecuteTime:"+lastExecuteTime); F_w
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//System.out.print(" now:"+now+"\n"); K-bD<X
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); Aw}"gpL
lastExecuteTime=now; RN$1bxY
executeUpdate(); JlH&??
} 'Y*E<6:
else{ nxUJN1b!N
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); |SoCRjuCPM
} tjIl-IQ
} {@eJtF+2
} vI:;A/&
//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 AqWUwK9T
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类写好了,下面是在JSP中如下调用。 ozmrw\_}[
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<% }#L^! \V}
CountBean cb=new CountBean(); )U~=Pf"
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); }+)fMZz
CountCache.add(cb); &~8oQC-eF
out.print(CountCache.list.size()+"<br>"); wN@oYFoL
CountControl c=new CountControl(); j/R[<47
c.run(); FG6h,7+
out.print(CountCache.list.size()+"<br>");
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