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: &RHZ7T
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CountBean.java = yFOH~_
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/* -d. i4X3j
* CountData.java Vb8Qh601
* q'Nafa&a)
* Created on 2007年1月1日, 下午4:44 E!9(6G4
* )H>?K0I
* To change this template, choose Tools | Options and locate the template under GGs7]mhA
* the Source Creation and Management node. Right-click the template and choose 4J1_rMfh
* Open. You can then make changes to the template in the Source Editor. F%:74.]Y
*/ UQg_y3
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package com.tot.count; <}p]0iA
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/** SajG67
* 8:;]tt
* @author X<D fzd oI
*/ uznYLS
public class CountBean { =fy\W=c
private String countType; DbSR(:
int countId; S"t\LB*'Ls
/** Creates a new instance of CountData */ jqj4(J@%yr
public CountBean() {} tVe =c
public void setCountType(String countTypes){ M>Q3;s
this.countType=countTypes; #N$\d4q9
} FHSFH>
public void setCountId(int countIds){ Hr7?#ZX;e
this.countId=countIds;
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} H_JE)a:+
public String getCountType(){ !rF1Remw
return countType; g t9(5p
} {r~=mQ
public int getCountId(){ *b_Iby-ZD
return countId; ULhXyItL
} $NCR
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} jz~#K;3=,
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CountCache.java J(K/z,4h
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/* D@O5G d
* CountCache.java @u`W(Ow
* OFBEJacy
* Created on 2007年1月1日, 下午5:01 }.pqV
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* PhPe7^
* To change this template, choose Tools | Options and locate the template under cs7^#/3<
* the Source Creation and Management node. Right-click the template and choose lQiw8qD
* Open. You can then make changes to the template in the Source Editor. &Z3%UOY
*/ &uF~t
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package com.tot.count; 5
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import java.util.*; 0y t36Du
/** omGzyuPF
* Qv`: E
* @author P*B@it
*/ 2
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public class CountCache { Hj(K*z
public static LinkedList list=new LinkedList(); c|(J%@B)
/** Creates a new instance of CountCache */ Caz5q|Oo
public CountCache() {} d#XgO5eyO
public static void add(CountBean cb){ <.Pt%Kg^BS
if(cb!=null){ $P#x>#+[A
list.add(cb); IN@o9pUjV
} h-|IZ}F7
} "]uPke@
} .vctuy&
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CountControl.java mr/?w0(C
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/* *N4/M%1P
* CountThread.java UmvnVmnv
* J<0d"'
* Created on 2007年1月1日, 下午4:57 )HC/J-
* kI9I{ &J&
* To change this template, choose Tools | Options and locate the template under IU5T5p
* the Source Creation and Management node. Right-click the template and choose =+UtAf<n
* Open. You can then make changes to the template in the Source Editor. ';Q8x?BS
*/ G[JWG
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package com.tot.count; _WvVF*Q"k
import tot.db.DBUtils; 9a=>gEF],@
import java.sql.*; z?Ok'LX
/** ,}]v7DD
* b9#(I~}
* @author ]{#=WTp]
*/ *l4[`7|
public class CountControl{ -)^vO*b 0
private static long lastExecuteTime=0;//上次更新时间 @MVul_@6
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 |U;O HS
/** Creates a new instance of CountThread */ 8AFc=Wx
public CountControl() {} {d*OJ/4
public synchronized void executeUpdate(){ _Y;tD
Connection conn=null; DO*
PreparedStatement ps=null; +v
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try{ n42\ty9
conn = DBUtils.getConnection(); ^\Z+Xq1~/
conn.setAutoCommit(false); 2"?D aX
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); qPD(D{,f$
for(int i=0;i<CountCache.list.size();i++){ d{Jk:@.1
CountBean cb=(CountBean)CountCache.list.getFirst(); Ex
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CountCache.list.removeFirst(); KpYezdPF)
ps.setInt(1, cb.getCountId()); &z1U0uk
ps.executeUpdate();⑴ &PRoT#,
//ps.addBatch();⑵ ohqThl
} ha$1vi}b
//int [] counts = ps.executeBatch();⑶ z`t~N
conn.commit(); \u{4=-C.
}catch(Exception e){ "Kp#Lx
e.printStackTrace(); #+l`tj4b/
} finally{ ("t'XKP&N
try{ QEf@wv;T
if(ps!=null) { 3.?be.cq
ps.clearParameters(); KS93v9|
ps.close(); KzO"$+M
ps=null; rkR5>S( 2M
} i(;`x
}catch(SQLException e){} FMeBsI9pL
DBUtils.closeConnection(conn); j;y~vX b
} -grf7w^
} $Q8
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public long getLast(){ $ch`.$wx
return lastExecuteTime; O7VEyQqf5
} EZ .3Z`
public void run(){ NT*r7_e
long now = System.currentTimeMillis(); i cTpx#|=
if ((now - lastExecuteTime) > executeSep) { T9Q3I
//System.out.print("lastExecuteTime:"+lastExecuteTime); T8z?_ *k
//System.out.print(" now:"+now+"\n"); Q l)hIf$Oo
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); B ??07j
lastExecuteTime=now; i^%$ydg
executeUpdate(); BNNM$.ZIQ
} g) oOravV
else{ NUltuM
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); s/IsrcfM
} I61S0lz/
} l(sVnhL6h
} `2s@O>RV
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 dn-
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类写好了,下面是在JSP中如下调用。 i)z|=
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<% Re8x!e'>
CountBean cb=new CountBean(); ,O5X80'.g
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); El<*)
CountCache.add(cb); =9a2+ v0
out.print(CountCache.list.size()+"<br>"); A%.mIc.
CountControl c=new CountControl(); l}z<q
c.run(); Dd5
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out.print(CountCache.list.size()+"<br>"); 4$&l`yWU+
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