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: eo"6 \3z
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CountBean.java t[%9z6t
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/* [K,&s8N5
* CountData.java 6dV92:
* Wk`G+VR+
* Created on 2007年1月1日, 下午4:44 Q']:k}y
* \3Ys8umKq
* To change this template, choose Tools | Options and locate the template under |0BmEF
* the Source Creation and Management node. Right-click the template and choose ,0;E_i7
* Open. You can then make changes to the template in the Source Editor. (',G
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*/ ;DBO
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package com.tot.count; -_v[oqf$
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/** P6dIU/w
* [p|-G*=00
* @author buq3t+0
*/ '3aDvV0
public class CountBean { -fn["R]
private String countType; ++BVn[ 1
int countId; ybcQ,e
/** Creates a new instance of CountData */ XV]`?
public CountBean() {} %.[t(F
public void setCountType(String countTypes){ |{<g-)
this.countType=countTypes; 1P@&xcvS\
} J8~3LE
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public void setCountId(int countIds){ WADNr8.
this.countId=countIds; g.Z>9(>;Y
} eLM_?9AZ!R
public String getCountType(){ 0(h *<g:
return countType; E XEae?
} pO4}6\1\
public int getCountId(){ ?E=&LAI#
return countId; 3T%WfS+
} aa8WRf
} /&Khk #
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CountCache.java 6(VCQ{
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/* W_ngB[
* CountCache.java ^;!A`t
* +3!um
* Created on 2007年1月1日, 下午5:01 `dx+Qp
* JO1KkIV
* To change this template, choose Tools | Options and locate the template under /m(vIl
* the Source Creation and Management node. Right-click the template and choose U_y)p Cd
* Open. You can then make changes to the template in the Source Editor. :;#Kg_bz
*/ \&n]W\
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package com.tot.count; WEZ(4ah
import java.util.*; s'J8E+&5
/** `b+f^6SJn
* H@.j@l
* @author !Yz~HO,u+
*/ 'cu(
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public class CountCache { .YKQ6
public static LinkedList list=new LinkedList(); m&EwX ^1-
/** Creates a new instance of CountCache */ s-J>(|
public CountCache() {} -H#{[M8xX
public static void add(CountBean cb){ D/"[/!
if(cb!=null){ l!EfvqWX
list.add(cb); ,0[bzk
} ==l p\
} YR=<xn;m.
} cL7je
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CountControl.java RgZBh04q
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/* EL;Ir tU
* CountThread.java w$u=_
* }[SWt3qV1
* Created on 2007年1月1日, 下午4:57 %F` cNw]
* /#GX4&z
* To change this template, choose Tools | Options and locate the template under JnlM0jc]`
* the Source Creation and Management node. Right-click the template and choose =;9Wh!{
* Open. You can then make changes to the template in the Source Editor. Y7zg
*/ s0~a5Ti3
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package com.tot.count; kVCSFF*
import tot.db.DBUtils; |[)t4A"}
import java.sql.*; FAz shR
/** k9vr6We'
* I QS|
* @author E;fYL]j/oZ
*/ Hl8-1M$&
public class CountControl{ v[q2OWcL
private static long lastExecuteTime=0;//上次更新时间 ;oH17
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ?54=TA|5`F
/** Creates a new instance of CountThread */ s*>s;S?{|
public CountControl() {} !;x
public synchronized void executeUpdate(){ T2AyQ~5~
Connection conn=null; $pyM<:*L&<
PreparedStatement ps=null; <!v^Df
try{ /QZnN?k
conn = DBUtils.getConnection(); 3?|Fn8dQR.
conn.setAutoCommit(false); ]8NNxaE3 (
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); !k)}p_e
for(int i=0;i<CountCache.list.size();i++){ rp6Y&3p.
CountBean cb=(CountBean)CountCache.list.getFirst(); >JkQU e
CountCache.list.removeFirst(); ;e_dk4_
ps.setInt(1, cb.getCountId()); vRpMZ)e
ps.executeUpdate();⑴ vQ#$.*Cvn
//ps.addBatch();⑵ 4_ztIrw
} !h4S`2oZ/
//int [] counts = ps.executeBatch();⑶ q.yS j
conn.commit(); &cV$8*2b^
}catch(Exception e){ VLQDktj&
e.printStackTrace(); /V+N
} finally{ tO~DA>R
try{ 7[rn
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if(ps!=null) { UeIu
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ps.clearParameters(); 3k`"%R.H
ps.close(); idMb}fw>
ps=null; 17I{_C
} m\(4y Gj
}catch(SQLException e){} R
rs?I,NV
DBUtils.closeConnection(conn); cKEf- &~
} B.-5$4*s
} :DXkAb2
public long getLast(){ +AhR7R!
return lastExecuteTime; ]tA39JK-i
} I\&..e0l
public void run(){ \bw71( Q
long now = System.currentTimeMillis(); PspH[db
if ((now - lastExecuteTime) > executeSep) { zmQ V6o=k
//System.out.print("lastExecuteTime:"+lastExecuteTime); %<6oKE
//System.out.print(" now:"+now+"\n"); IHZ WNT2
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 'S@%
lastExecuteTime=now; iA3d[%tBb
executeUpdate(); j0B, \A
} $Q{)AN;m
else{ 8>RGmue
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); {mY<R`Ee
} s-Q-1lKV,
} eS8tsI
} ,> A9OTSN\
//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 LzB)o\a
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类写好了,下面是在JSP中如下调用。 :WIbjI=
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<% =24)`Lyb
CountBean cb=new CountBean(); TOdH
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); .7++wo!,
CountCache.add(cb); "#z4
out.print(CountCache.list.size()+"<br>"); ck>|p09q'9
CountControl c=new CountControl(); 5V!L~#
c.run(); C18pK8-
out.print(CountCache.list.size()+"<br>"); y:WRpCZoa
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