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: [SKDsJRPP
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CountBean.java
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/* ]4')H;'y
* CountData.java Bn.R,B0PL
* oFt_ yU-
* Created on 2007年1月1日, 下午4:44 `6YN/"unfp
* UH7?JF-D
* To change this template, choose Tools | Options and locate the template under Az(,Q$"|5
* the Source Creation and Management node. Right-click the template and choose k^KpQ&n
* Open. You can then make changes to the template in the Source Editor. FKe/xz
*/ 2t0VbAO1{
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package com.tot.count; DP *$@5
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/** Jp8,s%
* +wHa)A0MW
* @author +?Q HSIQo
*/ ~U ]%>Zf
public class CountBean { !K= $Q Uq
private String countType; SEu:31k{o
int countId; "9~KVILlLu
/** Creates a new instance of CountData */ &liFUP?
public CountBean() {} =_6 Q26
public void setCountType(String countTypes){ {~#01p5
this.countType=countTypes; *. A-UoHa
} YOfYa
public void setCountId(int countIds){ tmeg=U7
this.countId=countIds; Dl\0xcE
} :.{d,)G
public String getCountType(){ \O~WMN
return countType; hr&UD| E=
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public int getCountId(){ ^4[QX
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return countId; E=bZ4 /
} KZ=5"a
} #!m^EqF1_
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CountCache.java $fPiR
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/* *Hv d
* CountCache.java a_D K"8I
* Xz/aytp~A
* Created on 2007年1月1日, 下午5:01 O|9Nl*rXz
* xkkG#n)
* To change this template, choose Tools | Options and locate the template under >Fe=PRs
* the Source Creation and Management node. Right-click the template and choose e9CvdR
* Open. You can then make changes to the template in the Source Editor. l{kacfk#
*/ ;ae6h
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package com.tot.count; p-z!i +
import java.util.*; '1G0YfG}n
/** 7 lq$PsC
* !l9#a{#6l
* @author e&mTaCLG
*/ #
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public class CountCache { sI4
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public static LinkedList list=new LinkedList(); ;>]dwsA*P
/** Creates a new instance of CountCache */ 20Rm|CNH?
public CountCache() {} lZ,$lZg9Z
public static void add(CountBean cb){ SS;'g4h\6
if(cb!=null){
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list.add(cb); i-sm 9K'ns
}
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} j{m{hVa
} nF
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CountControl.java X(]J\?n'
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/* a
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* CountThread.java ?xE'i[F @
* q}&+{dN\1
* Created on 2007年1月1日, 下午4:57 `KP}pi\
* +J !1z
* To change this template, choose Tools | Options and locate the template under c,*a|@
* the Source Creation and Management node. Right-click the template and choose 7z8
* Open. You can then make changes to the template in the Source Editor. 6U] "i
*/ z+?48}
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package com.tot.count; 9H%ixBnM
import tot.db.DBUtils; ><)fK5x
import java.sql.*; l-'\E6grdH
/** _<)HFg6
* ^P*+0?aFr
* @author gf,[GbZ
*/ c+<gc:#jy
public class CountControl{ wY7+E/
private static long lastExecuteTime=0;//上次更新时间 ,0n=*o@W
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 >LFj@YW_)
/** Creates a new instance of CountThread */ MIc(B_q
public CountControl() {} * \tR
public synchronized void executeUpdate(){ K$
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Connection conn=null; #XAH`L\
PreparedStatement ps=null; y)`q% J&
try{ 6c[ L*1
conn = DBUtils.getConnection(); &$pA,Gjin\
conn.setAutoCommit(false); =ZARJ40L
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); }An;)!>(nF
for(int i=0;i<CountCache.list.size();i++){ .wuRT>4G)G
CountBean cb=(CountBean)CountCache.list.getFirst(); ">R`S<W
CountCache.list.removeFirst(); RSF@ Oo{
ps.setInt(1, cb.getCountId()); o@|kq1m8
ps.executeUpdate();⑴ Ozc9y y!%
//ps.addBatch();⑵ }ev+WIERQV
} HK.Si]:
//int [] counts = ps.executeBatch();⑶ aDX4}`u
conn.commit(); dcN4N5r
}catch(Exception e){ &. "ltB
e.printStackTrace(); 7FP
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} finally{ \
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try{ S2
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if(ps!=null) { z&A#d
ps.clearParameters(); A@I3:V
ps.close(); toC|vn&P
ps=null; G)7J$4R
} h,2?+}Fn
}catch(SQLException e){} >
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DBUtils.closeConnection(conn); VD2o#.7*eu
} [N*`3UZk"
} `qr.@0whP
public long getLast(){ cN#f$
return lastExecuteTime; g+u5u\k
} ?}U l(
public void run(){ ~RnBs`&!
long now = System.currentTimeMillis(); {=kW?
if ((now - lastExecuteTime) > executeSep) { U{-[lpd
//System.out.print("lastExecuteTime:"+lastExecuteTime); 7e@Bkq0)
//System.out.print(" now:"+now+"\n"); V4x6,*)e
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ]"\XTL0
lastExecuteTime=now; OMN|ea.O
executeUpdate(); o(Ro/U(Wu
}
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else{ ]hA]o7k
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ${, !L l7)
} 5?gZw;yiv%
} I6F $@
} Y]HtO^T2
//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 U\", !S~<
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类写好了,下面是在JSP中如下调用。 }{
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<% )]m_ L$9
CountBean cb=new CountBean(); kpO+
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); <=!|U0YV
CountCache.add(cb); k.w}}78N2N
out.print(CountCache.list.size()+"<br>"); #+PfrS=
CountControl c=new CountControl(); 8*yky
c.run(); <<9Y=%C+
out.print(CountCache.list.size()+"<br>"); dZjh@yGP.
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