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: A<C`JN}
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CountBean.java Ayadvi(@P
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/* .#2YJ~
* CountData.java k`F$aQV9`
* h1^q};3!W\
* Created on 2007年1月1日, 下午4:44 ~ou*'
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* kQxY"HD
* To change this template, choose Tools | Options and locate the template under }:5AB93(
* the Source Creation and Management node. Right-click the template and choose sZ/~pk
* Open. You can then make changes to the template in the Source Editor. eva-?+n\q
*/ s +gZnne
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package com.tot.count; F0t!k>
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/** ZTfs&5
* D0Oh,Fe#M\
* @author + G#qS1
*/ y]xG@;4M
public class CountBean { :[3{-.c
private String countType; 0C#1/o)o
int countId; &B1d+.+
/** Creates a new instance of CountData */ ]rO`eN[~U
public CountBean() {} WoHFt*e2
public void setCountType(String countTypes){ g>_lU
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this.countType=countTypes; K, ae-#wgb
} OW<i"?0
public void setCountId(int countIds){ k6_RJ8I
this.countId=countIds; HeZ! "^w
} }#Z Q\[
public String getCountType(){ RY2`v
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return countType; t,4q]Jt
} \Lv
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public int getCountId(){ lpQsmd#
return countId; _Pjo9z
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} (1T2?mO
} , |CT|2D>
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CountCache.java ja3wXz$2
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/* In#V1[io
* CountCache.java W'hE,
* Yv\.QrxPm
* Created on 2007年1月1日, 下午5:01 awQf$
* .?UK`O2Q
* To change this template, choose Tools | Options and locate the template under <i``#"/
* the Source Creation and Management node. Right-click the template and choose 3P-qLbJ
* Open. You can then make changes to the template in the Source Editor. h7c8K)ntnf
*/ X3vTyIsn
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package com.tot.count; eN fo8xUG
import java.util.*; b*S:wfw
/** ,'?%z>RZm
* ER~m
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* @author 4J
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*/ >Ip>x!wi
public class CountCache { <"Z]S^>$
public static LinkedList list=new LinkedList(); L!x7]g,^
/** Creates a new instance of CountCache */ T%A45BE
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public CountCache() {} 3U9]&7^
public static void add(CountBean cb){ ("<3w2Vlh
if(cb!=null){ q$`{$RX
list.add(cb); ^o}!=aMr
} Pf5RlpL:p
} O?/\hZ"&c
} i% 19|an
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CountControl.java +h_'hz&HlS
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/* tz\7,yGT
* CountThread.java s7e)Mt
* {|=
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* Created on 2007年1月1日, 下午4:57 Sh(
* ;
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* To change this template, choose Tools | Options and locate the template under *xR;}%s\
* the Source Creation and Management node. Right-click the template and choose [0U!Y/?6lA
* Open. You can then make changes to the template in the Source Editor. Ymkk"y.w
*/ hG .>>
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package com.tot.count; _doX&*9u
import tot.db.DBUtils; dIgaw;Ch]
import java.sql.*; /_}xTP"9
/** GzxtC&
* FZ'|z8Dm
* @author <ek_n;R
*/ *jM~VTXwt
public class CountControl{ aRPgo0,W1
private static long lastExecuteTime=0;//上次更新时间 yb*P&si5bY
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ?3~]H
/** Creates a new instance of CountThread */ S7&w r@
public CountControl() {} pt .0%3
public synchronized void executeUpdate(){ UhQ [|c
Connection conn=null; XF(0>-
PreparedStatement ps=null; JYB"\VV
try{ j3jf:7 /\
conn = DBUtils.getConnection(); 2V%si 6
conn.setAutoCommit(false); #D~atgR
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); >Vz Gx(7q
for(int i=0;i<CountCache.list.size();i++){ (~}IoQp>
CountBean cb=(CountBean)CountCache.list.getFirst(); >U.TkB
CountCache.list.removeFirst(); |3`Sd;^;
ps.setInt(1, cb.getCountId()); )/kkvI()l
ps.executeUpdate();⑴ F!OVx<
//ps.addBatch();⑵ S'm&Ll2i@
} G,I[zhX\
//int [] counts = ps.executeBatch();⑶ a]XQM$T$
conn.commit(); c+chwU0W
}catch(Exception e){ Y^$^B,
e.printStackTrace(); o"dX3jd
} finally{ .^j 6
try{ X-&t!0O4}`
if(ps!=null) { #
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ps.clearParameters(); E/z^~;KA
ps.close(); ~H!s{$.5
ps=null; b)RU+9x &
} fQ c%a1'
}catch(SQLException e){} #s'9Ydd
DBUtils.closeConnection(conn); Wh6jr=>G
} d7s? c
} \o3)\
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public long getLast(){ , tJ%t#
return lastExecuteTime; ][3H6T!ckL
} pwAawm
public void run(){ SQx%CcW9d
long now = System.currentTimeMillis(); bE:oF9J?
if ((now - lastExecuteTime) > executeSep) { `_Iy8rv:P
//System.out.print("lastExecuteTime:"+lastExecuteTime); _|qJ)gD[
//System.out.print(" now:"+now+"\n"); \x?q!(;G2
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ,5^XjU3c=
lastExecuteTime=now; ;/?M&rX
executeUpdate(); \ cmt'b
} U,
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else{ 1sx@Nvlb
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ^]:w5\DG
} epM;u
} /.{4
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} oe,I vnt
//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 nI4Kuz`dF
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类写好了,下面是在JSP中如下调用。 ??eSGQ|
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<% ) *Mr{`
CountBean cb=new CountBean(); +k|t[N
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); JW[y
CountCache.add(cb); 5ZeE& vG2
out.print(CountCache.list.size()+"<br>"); m?cC 0(6
CountControl c=new CountControl(); 1xN6V-qk
c.run(); z%-Yz-G9
out.print(CountCache.list.size()+"<br>"); N>qOiw[
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