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: tm1UH 4
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CountBean.java Gb |}Su
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/* 2C]la
* CountData.java niHL/\7u
* jJ"EGFa8
* Created on 2007年1月1日, 下午4:44 s
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* 71" JL",
* To change this template, choose Tools | Options and locate the template under zMYd|2bc
* the Source Creation and Management node. Right-click the template and choose "I}Z2
* Open. You can then make changes to the template in the Source Editor. l5Wa'~0qA
*/ ?5v5:U(A
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package com.tot.count; )Ct*G=
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/** (5q%0|RzRs
* RYZE*lWUh
* @author c\MsVH2|
*/ 4JZHjf0M6
public class CountBean { AMD?LjY~
private String countType; ki~y@@3I
int countId; \}x'>6zr2
/** Creates a new instance of CountData */ ff}a <w
public CountBean() {} +e8>?dkq
public void setCountType(String countTypes){ 3[=`uO0\7
this.countType=countTypes; aR)en{W
} V9E6W*IE
public void setCountId(int countIds){ Lkl|4L
this.countId=countIds; h [IYA1/y
} CC>fm1#i\
public String getCountType(){ >U~|R=*
return countType; DqzA U7
} .?0>5-SfY
public int getCountId(){ q|u8CX
return countId; \_*MJ)h)X
} -[pCP_`)u
} HD:%Yv
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CountCache.java <P^hYj-swh
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/* 1n`1o-&l-
* CountCache.java .^LL9{?
* q^N0abzgP
* Created on 2007年1月1日, 下午5:01 ;sChxQ=.^
* SCurO9RN
* To change this template, choose Tools | Options and locate the template under wVp4c?s
* the Source Creation and Management node. Right-click the template and choose {x|kg;
* Open. You can then make changes to the template in the Source Editor. E./__Mz@
*/ '>e79f-O)
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package com.tot.count; zvGK6qCk
import java.util.*; TsX+. i'
/** 9PKoNd^e
* H9~%#&fF
* @author #A3v]'7B
*/ ~n/Aq*
public class CountCache {
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public static LinkedList list=new LinkedList(); J`r,_)J"2
/** Creates a new instance of CountCache */ {,Bb"0 \
public CountCache() {} _;e!ZZLG
public static void add(CountBean cb){ fQQsb 5=i
if(cb!=null){ "X5_-l
list.add(cb); 7V} ]C>G
} *^D@l%av;
} NT@YLhs?
} %'"HGZn b
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CountControl.java B` *f(
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/* /^'Bgnez
* CountThread.java MyH[v E^b
* G'O/JM
* Created on 2007年1月1日, 下午4:57 5 o#<`_=J
* {Z#e{~m#
* To change this template, choose Tools | Options and locate the template under >I4p9y(u
* the Source Creation and Management node. Right-click the template and choose |.(CIu~b
* Open. You can then make changes to the template in the Source Editor. 4bi NGl~
*/ zj>aaY
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package com.tot.count; [0&'cu>
import tot.db.DBUtils; M@~~f
import java.sql.*; Dn_"B0$lk
/** 2~!R*i
* dI^IK
* @author ufw3H9F(O
*/ 2e9jo,i
public class CountControl{ h(@R]GUX
private static long lastExecuteTime=0;//上次更新时间 <)O>MI'
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private static long executeSep=60000;//定义更新间隔时间,单位毫秒 C,A!tj7@
/** Creates a new instance of CountThread */ &|.hkR2k
public CountControl() {} :reP} Da7q
public synchronized void executeUpdate(){ 3`A>j"
Connection conn=null; |(V?,^b^ro
PreparedStatement ps=null; pWs\.::B
try{ +Qh[sGDdY
conn = DBUtils.getConnection(); F$Im9T6
conn.setAutoCommit(false); D XV@DQ
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 7}4'dW.
for(int i=0;i<CountCache.list.size();i++){ <nWKR,
CountBean cb=(CountBean)CountCache.list.getFirst(); , 3X: )
CountCache.list.removeFirst(); TN35CaSmq
ps.setInt(1, cb.getCountId()); ZfPd0 p
ps.executeUpdate();⑴ jt{9e:2%
//ps.addBatch();⑵ >Mvka;T]
} ~x|aoozL
//int [] counts = ps.executeBatch();⑶ ~:>AR` 9G
conn.commit(); L[?nST18%
}catch(Exception e){ Kt
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e.printStackTrace(); "z^(dF|
} finally{ q,B3ru.?d
try{ e~{^oM
if(ps!=null) { FR
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ps.clearParameters(); E *F*nd]K
ps.close(); w6T[hZ 9
ps=null; '>j<yaD'
} Ia629gi5s
}catch(SQLException e){} :qKF58W
DBUtils.closeConnection(conn); TUh&d5a9H
} l~bKBz
} Jyj0Gco
public long getLast(){ 6HoqEku/Q
return lastExecuteTime; [X,A'Q
} ugYw<
public void run(){ /+VIw`E
long now = System.currentTimeMillis(); CjZZm^O
if ((now - lastExecuteTime) > executeSep) { ?Z q_9T7
//System.out.print("lastExecuteTime:"+lastExecuteTime); w*50ZS;N
//System.out.print(" now:"+now+"\n"); 55.;+B5L*
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); } h[>U
lastExecuteTime=now; CI`N8
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executeUpdate(); s%~L4Wmcq
} <i{K7}':
else{ .xO
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//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); !;%y$$gxh
} /XcDYMKgh
} dY} pN"
} zJ9v%.e
//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 dUS ZNY
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类写好了,下面是在JSP中如下调用。 lT]=&m>
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<% b1u}fp
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CountBean cb=new CountBean(); g\Wj+el}
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 9UwLF`XM
CountCache.add(cb); #G_F`&
out.print(CountCache.list.size()+"<br>"); Sw)i1S9
CountControl c=new CountControl(); ncv7t|ZN
c.run(); Bv$UFTz
out.print(CountCache.list.size()+"<br>"); ;7Y[c}V1^
%>