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: K6C@YY(
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CountBean.java Y|NL #F
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/* /hNZ7\|P
* CountData.java @zz4,,]
* TB!z:n
* Created on 2007年1月1日, 下午4:44 _[eAA4h
* ;r**`O
* To change this template, choose Tools | Options and locate the template under ,-55*Rb i
* the Source Creation and Management node. Right-click the template and choose .Xq4QR .
* Open. You can then make changes to the template in the Source Editor. 7'pmW,;
*/ n/>^!S
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package com.tot.count; ncF|wz
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/** Pz=x$aY
* Xup"gYTZQ
* @author "r:i
*/ D^R=
public class CountBean { X4- _l$j
private String countType; **].d;~[l
int countId; x/Nh9hh"
/** Creates a new instance of CountData */ YPq4VX,
public CountBean() {} O.ce"5Y^
public void setCountType(String countTypes){ C`p)S`d
this.countType=countTypes; 5x([fG
} F4Jc7k2
public void setCountId(int countIds){ st|;]q9?
this.countId=countIds; L<GF1I)
} ~E]ct F
public String getCountType(){ ZmJ!ZKKch
return countType; _8-iO.T+2
} (W=J3?hn
public int getCountId(){ ;w\7p a
return countId; 2}NWFM3C
} 2HxT+|~d6
} 88K=jo))b
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CountCache.java 3G4N0{i
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/* ^oL43#Nlo
* CountCache.java `{1&*4!
*
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* Created on 2007年1月1日, 下午5:01 W.B>"u
* 47GL[ofY
* To change this template, choose Tools | Options and locate the template under tA*hh"9
* the Source Creation and Management node. Right-click the template and choose K GVAP
* Open. You can then make changes to the template in the Source Editor. [<2#C#P:6
*/ BdK2I!mm
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package com.tot.count; CY"iP,nHl
import java.util.*; dn"&j1@KY
/** pl-2O $
* U c6]]Bbc
* @author 5tSR2gG#K,
*/ _tl,-}~
public class CountCache { }I1A4=d
public static LinkedList list=new LinkedList(); "0,d)L0,"
/** Creates a new instance of CountCache */ \`nRgYSE
public CountCache() {} Q|!}&=
public static void add(CountBean cb){ w<m)T
if(cb!=null){ vf|lF9@U
list.add(cb); } Fw/WD
} gK`o;` ^
} +IRr&J*P
} pPC_ub
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CountControl.java "agc*o~!F
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/* J?Ed^B-
* CountThread.java :9_N
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* _fVC\18T
* Created on 2007年1月1日, 下午4:57 ZPM,ZGlu:
* ?gq',FFDq
* To change this template, choose Tools | Options and locate the template under qWQ7:*DL
* the Source Creation and Management node. Right-click the template and choose |L@9qwF
* Open. You can then make changes to the template in the Source Editor. 8Wa&&YTB
*/ ))pp{X2m
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package com.tot.count; :X?bWxOJ
import tot.db.DBUtils; #Cwzk{p(
import java.sql.*; S$=e %c
/** .7BB*!CP
* OG M9e!
* @author eH*u,/
*/ m((A
public class CountControl{
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private static long lastExecuteTime=0;//上次更新时间 !uC`7a
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 }G:5P3f
/** Creates a new instance of CountThread */ rvdhfM!-A
public CountControl() {} [i8,rOa7
public synchronized void executeUpdate(){ FUq>+U!Qu
Connection conn=null; _$W</8<
PreparedStatement ps=null; cH5@Jam
try{ 6X@]<R
conn = DBUtils.getConnection(); v}$s,j3NO
conn.setAutoCommit(false); nDdF(|Qt
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); [lSQ?
for(int i=0;i<CountCache.list.size();i++){ ;[)t*yAh
CountBean cb=(CountBean)CountCache.list.getFirst(); liYR8 D
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CountCache.list.removeFirst(); 5M.KF;P
ps.setInt(1, cb.getCountId()); Gk.;<d
ps.executeUpdate();⑴ %
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//ps.addBatch();⑵ a^9-9*
} :6,qp?/
//int [] counts = ps.executeBatch();⑶ m4U7{sE
conn.commit(); hhS]wM?B
}catch(Exception e){ ,O9rL :?
e.printStackTrace(); F$Cf\#{3
} finally{ X j'7nj
try{ rCwjy&SuU^
if(ps!=null) { v7"Hvp3w
ps.clearParameters(); 64#6L.Q-c
ps.close(); d/Sx+1
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ps=null; W|go*+`W%
} GM5s~,
}catch(SQLException e){} ZQd\!K8y^Q
DBUtils.closeConnection(conn);
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} [M^ur%H
} `=]I-5#.W
public long getLast(){ *-!&5~o/U
return lastExecuteTime; aYjFRH`
} U9om}WKO
public void run(){ vFKt=o$ g
long now = System.currentTimeMillis(); .kBZ(`K
if ((now - lastExecuteTime) > executeSep) { F-=W7 D:[c
//System.out.print("lastExecuteTime:"+lastExecuteTime); IT`r&;5
//System.out.print(" now:"+now+"\n"); 9$9Pv%F:j
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); nUAs:Q
lastExecuteTime=now; c'9-SY1'~
executeUpdate(); HMUn+kk+
} @ =RH_NB
else{ =5JTVF
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); Qi_De
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} G1Qc\mp
} IZ2c<B5&
} -?8;-h, h
//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 (I bT5
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类写好了,下面是在JSP中如下调用。 )8H5ovj.
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<% c`'2
CountBean cb=new CountBean(); }v'jFIkhI
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); (5l5@MN
CountCache.add(cb); FyXz(l:
out.print(CountCache.list.size()+"<br>"); K22' XrN
CountControl c=new CountControl(); [6bK>w"v
c.run(); zU+` o?al
out.print(CountCache.list.size()+"<br>"); cVzOW|NVx
%>