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: 4:%El+,_Y
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CountBean.java 's7 SZ$(
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/* qw
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* CountData.java gOES2
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* g# 9*bF
* Created on 2007年1月1日, 下午4:44 ?=|)n%
* fxtYo,;$
* To change this template, choose Tools | Options and locate the template under @'NaA SB
* the Source Creation and Management node. Right-click the template and choose n'x`oI)-
* Open. You can then make changes to the template in the Source Editor. XSHwE)m
*/ )P(d66yq'u
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package com.tot.count; e5"-4udCn
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/** bCY^.S-
* q)z1</B-
* @author &a2V-|G',
*/ U(Hq4D
public class CountBean { }~Kyw7?
private String countType; wzLiVe-
int countId; CpP$HrQ
/** Creates a new instance of CountData */ B 3,ig9
public CountBean() {} 4o)\DB?!
public void setCountType(String countTypes){ ?G%, k
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this.countType=countTypes; E%J7jA4
} {ZBb.$}RC
public void setCountId(int countIds){ yW6[Fpw
this.countId=countIds; a s<q
} Lu#@~
public String getCountType(){ /KJx n6
return countType; MR l*rK
} /S=;DxZ,r
public int getCountId(){ 2}xFv2X
return countId; NdED8 iRc
} s_Ge22BZ
} 1+PNy d
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CountCache.java 'k(~XA}X:
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/* ~1wdAq`'a
* CountCache.java GO:1
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* J?,!1V=
* Created on 2007年1月1日, 下午5:01 5)SZd)
* '\E*W!R.]
* To change this template, choose Tools | Options and locate the template under iw]BQjK
* the Source Creation and Management node. Right-click the template and choose 3K'o&>}L
* Open. You can then make changes to the template in the Source Editor. me}Gb a
*/ dO4U9{+
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package com.tot.count; ;HLMU36q
import java.util.*; <J_,9&\J
/** 77=y!SDP
* C6=;(=?C
* @author 'm p{O
*/ XtH_+W+O
public class CountCache { +/_B/[e<>
public static LinkedList list=new LinkedList(); z&HN>7
/** Creates a new instance of CountCache */ :Ro"
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public CountCache() {} TXvt0&-
public static void add(CountBean cb){ `))J8j"
if(cb!=null){ KlX |PQ
list.add(cb); bEXHB
} I>4Tbwy.-
} u4*]jt;H
} ]2sZu7
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CountControl.java Z?!:=x>7m
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/* T[$hYe8%^
* CountThread.java $^+KR]\q
* Z-sN4fr a
* Created on 2007年1月1日, 下午4:57 v.^
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* $X\`
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* To change this template, choose Tools | Options and locate the template under 63dtO{:4
* the Source Creation and Management node. Right-click the template and choose 2Z9gOd<M~
* Open. You can then make changes to the template in the Source Editor. G|Yp<W%o
*/ Px?At5
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package com.tot.count; 0-MasI&b
import tot.db.DBUtils; +mQC:B7>
import java.sql.*; G`JwAy r'
/** yLa5tv/
* g#<?OFl
* @author =
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*/ ZzaW@6LJF
public class CountControl{ ' ^L
private static long lastExecuteTime=0;//上次更新时间 hw.demD
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 hs#s $})}Z
/** Creates a new instance of CountThread */ 0~L8yMM
public CountControl() {} wTAEJ{p
public synchronized void executeUpdate(){ xp;8p94
Connection conn=null; w#bbm'j7r
PreparedStatement ps=null; .1q~,}toX
try{ &l}xBQAL
conn = DBUtils.getConnection(); \U =>
conn.setAutoCommit(false); 28qWC~/9
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 8 P y_Y>
for(int i=0;i<CountCache.list.size();i++){ DdZ_2B2
CountBean cb=(CountBean)CountCache.list.getFirst(); `YU:kj<6
CountCache.list.removeFirst(); \7w85$
ps.setInt(1, cb.getCountId()); 5}^08Xl
ps.executeUpdate();⑴ L5|;VH
//ps.addBatch();⑵ SE-, 1p
} Kz2^f@5=F
//int [] counts = ps.executeBatch();⑶ bzL;)H4Eo
conn.commit(); ,?N_67
}catch(Exception e){ KdQ|$t
e.printStackTrace(); FbNQ
} finally{ ^WYG?/{4
try{ EjCzou
if(ps!=null) { 2
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ps.clearParameters(); 2X|jq4
ps.close(); 4)Wzj4qW
ps=null; 0+`*8G)
} $,v+i
-
}catch(SQLException e){} Z42 Suy
DBUtils.closeConnection(conn); 0_Z|y/I.
} f6A['<%o
} F"? *@L
public long getLast(){ ?BZ`mrH^
return lastExecuteTime; ?U[nYp}"v
} $W]guG
public void run(){ 48*pKbbM4
long now = System.currentTimeMillis(); QL!+.y%
if ((now - lastExecuteTime) > executeSep) { ;xC~{O
//System.out.print("lastExecuteTime:"+lastExecuteTime); HQj4h]O#
//System.out.print(" now:"+now+"\n"); JWjp<{Q;1
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); +uXnFf d^
lastExecuteTime=now; "JGig!9
executeUpdate(); +GtGyp
} ^7<m lr
else{ weadY,-H8
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); g5N<B+?!i
} (w
} ,colGth54
} dllf~:b
//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 fszeJS}Dw
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类写好了,下面是在JSP中如下调用。 AS^$1i:
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<% ~4gKAD
CountBean cb=new CountBean(); &jd<rs5}
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); }ZGpd9D
CountCache.add(cb); &8L\FAY0%9
out.print(CountCache.list.size()+"<br>"); TTak[e&j3
CountControl c=new CountControl(); 3Ya6yz
c.run(); 'UCx^-
out.print(CountCache.list.size()+"<br>"); Gf.o{
%>