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: u c7Y8iO
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CountBean.java 2M1yw "
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/* ~{d94o.
* CountData.java o_\b{<^I
* 6[qRb+ds
* Created on 2007年1月1日, 下午4:44 N?87Bd
* df8rf8B-
* To change this template, choose Tools | Options and locate the template under @ZX{q~g!
* the Source Creation and Management node. Right-click the template and choose VK`b'U&l"
* Open. You can then make changes to the template in the Source Editor. sBSBDjk[
*/ Yq5}r?N
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package com.tot.count; 1N#TL"lMS
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/** "?avb`YU'
* uVisU%p
* @author %FyB\IQ
*/ 4]
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public class CountBean { p1Lx\
private String countType; AA05wpu8
int countId; \uanQ|Nu
/** Creates a new instance of CountData */ |:
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public CountBean() {} :;??!V
public void setCountType(String countTypes){ >Zmpsa+
this.countType=countTypes; 1 !\pwd@{
} UdLC]
public void setCountId(int countIds){ d,D)>Y'h
this.countId=countIds; Wg}#{[4
} Q g"{F},4
public String getCountType(){ s0nihX1Z-
return countType; %LVk%kz
} v3]q2*`G#
public int getCountId(){ Ir}&|"~H
return countId; Nw|Lrn*h!
} j83p[qR7o
} G_AAE#r`
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CountCache.java &"^A
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/* /!%P7F
* CountCache.java 8n&" ,)U
* c~C :"g.y
* Created on 2007年1月1日, 下午5:01 vDBnWA
* ~CM{?{z;
* To change this template, choose Tools | Options and locate the template under ff:&MsA|,
* the Source Creation and Management node. Right-click the template and choose J v)]7u
* Open. You can then make changes to the template in the Source Editor. (.n"
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*/ _$=xa6YA
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package com.tot.count; "[#jq5>
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import java.util.*; F48`1+
/** N!Y'W)i16
* /pyKTZ|
* @author Y[x ^59
*/ crhck'?0
public class CountCache { xaeY^"L
public static LinkedList list=new LinkedList(); nh E!Pk
/** Creates a new instance of CountCache */ 8^4X/n
public CountCache() {} ::M/s#-@
public static void add(CountBean cb){ zBjqYqZ<+
if(cb!=null){ h_A}i2/{
list.add(cb); LRbevpZ,
} 2%@j<yS
} uF^+}Y ZT
} C ch1"j<k$
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CountControl.java XhIgzaGVu
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/* 0kiW629o
* CountThread.java |Ec $%
* 3]c<7vdl
* Created on 2007年1月1日, 下午4:57 D#k>.)g
* Ws1<Jt3/."
* To change this template, choose Tools | Options and locate the template under }wv$ #H[
* the Source Creation and Management node. Right-click the template and choose #lB[]2]N
* Open. You can then make changes to the template in the Source Editor. @u$oqjK
*/ <B`=oO%o
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package com.tot.count; _nTjCN625
import tot.db.DBUtils; H%sQVE7m
import java.sql.*; *2>%>qu
/** uvmNQg
* Ak9W8Z}
* @author 4ErDGYg}
*/ )FHaJ*&d
public class CountControl{ _6(zG.Fg
private static long lastExecuteTime=0;//上次更新时间 {+r?g J
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 zJx<]=]
/** Creates a new instance of CountThread */
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public CountControl() {} ,-{j.
public synchronized void executeUpdate(){ u_Q3v9
Connection conn=null; lI5{]?'
PreparedStatement ps=null; #2WBYScW0
try{ Vy5Q+gw
conn = DBUtils.getConnection(); :X$&gsT/,
conn.setAutoCommit(false); 4XKg3l1
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); <~Y4JMr"
for(int i=0;i<CountCache.list.size();i++){ wvc?2~`
CountBean cb=(CountBean)CountCache.list.getFirst(); r^\^*FD |
CountCache.list.removeFirst(); Q 5jP`<zWU
ps.setInt(1, cb.getCountId()); h]zx7zt-
ps.executeUpdate();⑴ ?]7ITF
//ps.addBatch();⑵ [&zP$i&
} i"-#1vy=
//int [] counts = ps.executeBatch();⑶ VK NCK
conn.commit(); .:lzT"QXI
}catch(Exception e){ D<rjxP
e.printStackTrace(); ]&9f:5',
} finally{ |]I?^:I
try{ Ik}*7D
if(ps!=null) { !c*^:0
ps.clearParameters(); T}\U:@b
ps.close(); F\]rxl4(L
ps=null; ;bA9(:?
} J%[K;WjrZJ
}catch(SQLException e){} WUHx0I
DBUtils.closeConnection(conn); Dv hK0L*Qr
} kQH!`-n:T
} .<j8>1
public long getLast(){ 3s|tS2^4
return lastExecuteTime; -({\eL$n
} L~yy;)]W
public void run(){ gZPJZN/cpz
long now = System.currentTimeMillis(); w6E?TI
if ((now - lastExecuteTime) > executeSep) { CId`6W
//System.out.print("lastExecuteTime:"+lastExecuteTime); C&;'Pw9H
//System.out.print(" now:"+now+"\n"); F^aD!O ~
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); r1=Zoxc=w
lastExecuteTime=now; 9Qkww&VEk
executeUpdate(); JEP"2M N,
} iF
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else{ N..u<06j/
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 2`Pk@,:_
} %V+,#
} Us%VBq
} /g8yc'{p
//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 j"NqNv
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类写好了,下面是在JSP中如下调用。 =_wgKXBFa
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<% yV]-![`D
CountBean cb=new CountBean(); zcNV<tx
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); (nc fR
CountCache.add(cb); T2Vj&EA@
out.print(CountCache.list.size()+"<br>"); )kd)v4#
CountControl c=new CountControl(); %r>vZ/>a
c.run(); @TH \hr]
out.print(CountCache.list.size()+"<br>"); /vQ^>2X%
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