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: nN3$\gHp8i
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CountBean.java Iia.k'N
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/* ^ie^VY($
* CountData.java M8@_Uj
* *OdX u&5
* Created on 2007年1月1日, 下午4:44 g6sjc,`
* s(&;q4|
* To change this template, choose Tools | Options and locate the template under S*)o)34U
* the Source Creation and Management node. Right-click the template and choose q9dLHi<1
* Open. You can then make changes to the template in the Source Editor. 4S
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*/ }~o
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package com.tot.count; >!9h6BoGV
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/** Jbp5'e
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* (Btv ClZ
* @author y~F<9;$=
*/ ^GYq#q9Q
public class CountBean { j5%qv(w
private String countType; @ERu>nSP
int countId; WA
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/** Creates a new instance of CountData */ =V|Nn0E
public CountBean() {} ?z"KnR+?Q
public void setCountType(String countTypes){ WwW^[k (X
this.countType=countTypes; ~4)Y#IxL
} }#= Od e
public void setCountId(int countIds){ [.q(h/b
this.countId=countIds; vZajT!h
} K@@9:T$
public String getCountType(){ >Wh3MG6
return countType; =Mhg
} PaVO"y]C
public int getCountId(){ b4 hIeBI\
return countId; yty`2$O
} =J@`0H"
} 4R +P
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CountCache.java xaL#MIR"u"
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/* ]@SU4
* CountCache.java 00M`%c/
* p\U*;'hv
* Created on 2007年1月1日, 下午5:01 DMkhbo&+
* {TL +7kiX/
* To change this template, choose Tools | Options and locate the template under Z~3u:[x";
* the Source Creation and Management node. Right-click the template and choose 6~Wu`
* Open. You can then make changes to the template in the Source Editor. viuiqs5[Bi
*/
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package com.tot.count; JfTfAq]
import java.util.*; FD6v/Y
/**
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* n9fk,3
* @author "g
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*/ g8yN%)[
public class CountCache { _=6 OP8
public static LinkedList list=new LinkedList(); ^'B-sz{{
/** Creates a new instance of CountCache */ u3Do~RyL[
public CountCache() {} F^'v{@C
public static void add(CountBean cb){ ?Bu}.0ku-$
if(cb!=null){ tF`MT%{Va
list.add(cb); )!C7bTv 4
} <*YO~S(R
} ;,0lUcV
} \n@V-b
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CountControl.java S?,_<GD)w
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/* +5*vABvCu
* CountThread.java y`b\;kd
* +v[O
* Created on 2007年1月1日, 下午4:57 wZv-b*4
* n+quSF)
* To change this template, choose Tools | Options and locate the template under ,#aS/+;[)
* the Source Creation and Management node. Right-click the template and choose 6+8mV8{-8
* Open. You can then make changes to the template in the Source Editor. Wg(bD,
*/ N?+eWY
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package com.tot.count;
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import tot.db.DBUtils; H'h#wV`(
import java.sql.*; Q>IH``1*e
/** ih!~G5Xi9i
* <9\,QR)
* @author 01nsdZ-
*/ -]QguZE
public class CountControl{ MW]8;`|jC
private static long lastExecuteTime=0;//上次更新时间 Xb+3Xn0}&8
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 (zmNa}-
/** Creates a new instance of CountThread */ 8&T,LNZoY
public CountControl() {} kr{)
public synchronized void executeUpdate(){ M;qb7Mu
Connection conn=null; q5?L1
PreparedStatement ps=null; 966<I56+
try{ a)S(p1BGg
conn = DBUtils.getConnection(); +\U]p_Fo3
conn.setAutoCommit(false); h^d\xn9GT#
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); VV\Xb31J
for(int i=0;i<CountCache.list.size();i++){ !2tw, QM
CountBean cb=(CountBean)CountCache.list.getFirst(); e;;):\p4
CountCache.list.removeFirst(); SKJW%(|3
ps.setInt(1, cb.getCountId()); ~BQV]BJ7
ps.executeUpdate();⑴ Bhx<g&|j
//ps.addBatch();⑵ l% |cB93
} C.HYS S
//int [] counts = ps.executeBatch();⑶ k<, u0
conn.commit(); #gI&lO*\gr
}catch(Exception e){ <Cr8V'c
e.printStackTrace(); L"^.0*X/d
} finally{ wDZ
try{ ~B*~'I9b*
if(ps!=null) { *N'hA5.z
ps.clearParameters(); .ujj:>
ps.close(); 'g]=.K+@}
ps=null; mo*'"/
} :K;T Q
}catch(SQLException e){} zS?n>ElI
DBUtils.closeConnection(conn); @% H8"A
} 5&G
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} .d
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public long getLast(){ IW] *i?L
return lastExecuteTime; YJc%h@ _=]
} Nor`c+,4
public void run(){ NZ)b:~a
long now = System.currentTimeMillis(); &PSTwZd
if ((now - lastExecuteTime) > executeSep) { [88{@)
//System.out.print("lastExecuteTime:"+lastExecuteTime); r!~(R+,c
//System.out.print(" now:"+now+"\n"); X
[!X>w&z|
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); .c: )Qli
lastExecuteTime=now; rd|crD3
executeUpdate(); (tpof
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} WzlS^bZ
else{ -^Rb7 g-
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); iz$FcA]
} +
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} }z?xGW/k
} 8Y xhd
.
//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 &!6DC5
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类写好了,下面是在JSP中如下调用。 .
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<% O!yakU+
CountBean cb=new CountBean(); r/^tzH's
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 0w'|d@*wV
CountCache.add(cb); \.kTe<.:_
out.print(CountCache.list.size()+"<br>"); 9='=-;@/5
CountControl c=new CountControl(); IJldN6&\q
c.run(); AX8gij
out.print(CountCache.list.size()+"<br>"); >"O1`xdG
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