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: qvu1 u
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CountBean.java 'V^M+ng
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/* \E,2VM@6
* CountData.java ?=4oxPe
* =YVxQj
* Created on 2007年1月1日, 下午4:44 .9e5@@VR
* !;8Y?c-D
* To change this template, choose Tools | Options and locate the template under qdZ ^D
* the Source Creation and Management node. Right-click the template and choose 7xO05)bz
* Open. You can then make changes to the template in the Source Editor. PcA^ jBgGl
*/ EpG9t9S9
[- 92]
package com.tot.count; ` Ny(S2
# *pB"L
/** 'kj
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* :k?`gm$
* @author ;/kd.Q
*/ @k;65'"Q
public class CountBean { VD&wO'U
private String countType; @yb'h`f]
int countId; m%u`#67oK
/** Creates a new instance of CountData */ f_O|
public CountBean() {} &iw,||#
public void setCountType(String countTypes){ mD7NQ2:wA
this.countType=countTypes; j[i*;0) |
} zqt<[=O
public void setCountId(int countIds){ sE&nEc
this.countId=countIds; r=3`Eb"t
} iJhieNn
public String getCountType(){ Z<>gx m<
return countType; 7r?,wM
} Y>aVnixx<
public int getCountId(){ U/{t" e
return countId; J?TCP%
} Xh}q/H<
} USEmD5 q
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CountCache.java }iDRlE,
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/* H0inU+Ih
* CountCache.java =7TWzUCO#
* pSC{0Y$g
* Created on 2007年1月1日, 下午5:01 A4(L47^
* M:OZWYQ
* To change this template, choose Tools | Options and locate the template under <-N eusx%
* the Source Creation and Management node. Right-click the template and choose xib}E[-l#
* Open. You can then make changes to the template in the Source Editor. JdI*@b2k[
*/ yn ofDGAf
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package com.tot.count; 7Fpa%N/WL
import java.util.*; EwG+' nlE
/** ?MSZO]Q4+
* HLz<C
* @author ha|2u(4
*/ X~m57bj
public class CountCache { :CM-I_6
public static LinkedList list=new LinkedList(); 9$v\D3<Z
/** Creates a new instance of CountCache */ *-]k([wV
public CountCache() {} i| cA)
public static void add(CountBean cb){ |%8t.Z
if(cb!=null){ vh"';L_*37
list.add(cb); gYbvCs8O!
} _5n2'\] H`
} FEhBhv|m
} rMWvW(@@D
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CountControl.java PT,*KYF_O"
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/* <hy!B4
* CountThread.java 8bMw.u=F
* m8L %!6o
* Created on 2007年1月1日, 下午4:57 \4$Nx/@Q}
* ?~.9:93
* To change this template, choose Tools | Options and locate the template under E l.eK9L
* the Source Creation and Management node. Right-click the template and choose dk]
* Open. You can then make changes to the template in the Source Editor. (:~_#BA
*/ pvt/{
#q34>}O< O
package com.tot.count; 6T~+vT
import tot.db.DBUtils; Kg2@]J9m
import java.sql.*; Vt zSM%=
/** % O%;\t
* n3J,`1*ct
* @author oU3gy[wF;b
*/ N0lFx?4
public class CountControl{ `,pBOh|'
private static long lastExecuteTime=0;//上次更新时间 fU.hb%m)Q\
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 .6n|hYe
/** Creates a new instance of CountThread */ w0js_P-uv
public CountControl() {} sdXchVC
public synchronized void executeUpdate(){ .w\4Th#
Connection conn=null; a&[[@1OY
PreparedStatement ps=null; &flcJ`
try{ ~O./A-l
conn = DBUtils.getConnection(); M[b~5L+S
conn.setAutoCommit(false); (1{OQ0N+x
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); A+Je?3/.
for(int i=0;i<CountCache.list.size();i++){ ocW`sE?EED
CountBean cb=(CountBean)CountCache.list.getFirst(); cQh{z8Bf?<
CountCache.list.removeFirst(); (ce)A,;
ps.setInt(1, cb.getCountId()); zXGI{P0O
ps.executeUpdate();⑴ Q!~1Xc0S`p
//ps.addBatch();⑵
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} b2F1^]p
//int [] counts = ps.executeBatch();⑶ %E,-dw
conn.commit(); 79Q,XRWh|
}catch(Exception e){ 3s:)CXO
e.printStackTrace(); <C"}OW8
} finally{ gcX
try{ ]]V=\.y
if(ps!=null) { h;K9}w
ps.clearParameters(); :1iXBG\
ps.close(); <9=RLENmY"
ps=null; QQHC
1
} 6*ZZ)W<
}catch(SQLException e){} Tig6<t+Q
DBUtils.closeConnection(conn); :i?c
} Qw%0<~<
} Z#%77!3
public long getLast(){ )Knsy
return lastExecuteTime; 8v;T_VN
} 0\$Lnwp_
public void run(){ ^kB9
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long now = System.currentTimeMillis(); 0Z%<H\Z
if ((now - lastExecuteTime) > executeSep) { S!}pL8OE
//System.out.print("lastExecuteTime:"+lastExecuteTime); T?__
//System.out.print(" now:"+now+"\n"); ~;I{d7z,;
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); mOjl0n[To]
lastExecuteTime=now; i3Nt?FSN
executeUpdate(); +xmZK<{<
} Git2Cet
else{ SR)@'-Wd
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); '?fn} V
} 78b9Sdi&
} [iSLn3XXRX
} +fIyeX
//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 JR_c]AQYu
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类写好了,下面是在JSP中如下调用。 [7)#3
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<% -gS/
CountBean cb=new CountBean(); pk=z<OTb
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); M[T!AO-S$
CountCache.add(cb); p:U{3uN 62
out.print(CountCache.list.size()+"<br>"); 3^&pb
CountControl c=new CountControl(); ] @1ncn7N
c.run(); RzSN,bLR
out.print(CountCache.list.size()+"<br>"); p7O4CP>9[
%>