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: YbZ<=ZzO4
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CountBean.java ]PdpC"
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/* S!J.$Y<Ko
* CountData.java x)<5f|j
* oH~ZqX.3
* Created on 2007年1月1日, 下午4:44 TnET1$@qr*
* y@g{:/cmO
* To change this template, choose Tools | Options and locate the template under g;en_~g3j
* the Source Creation and Management node. Right-click the template and choose K]dqK'
* Open. You can then make changes to the template in the Source Editor. PZ69aZ*Gs
*/ t!^FWr&
[;B_ENV
package com.tot.count; 9/C0DDb
j}YZl@dYV
/** @(.?e<
* -F,o@5W>Y
* @author U,/NygB~
*/ R`=IYnoOA
public class CountBean { <x@\3{{U
private String countType; e2w$":6>
int countId; ixN>KwH
/** Creates a new instance of CountData */ aq3evm
public CountBean() {} :6LOb f\01
public void setCountType(String countTypes){ uE:#m.Q
this.countType=countTypes; ;@K,>$ur-
} @t`|w.]ml
public void setCountId(int countIds){ Q(m} Sr4
this.countId=countIds; G 8|[.n
} AG)N^yd
public String getCountType(){ [:$j<}UmB
return countType; /b@0HL?
} >K#Z]k
public int getCountId(){ Jl3l\I'
return countId; !7J;h{3Uw
} Z91gAy^z<
} FM9b0qE
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CountCache.java
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/* b0LjNO@<
* CountCache.java OB3AZH$
* ><OdHRh@#
* Created on 2007年1月1日, 下午5:01 z2t;!]"'l
* "Gcr1$xG8!
* To change this template, choose Tools | Options and locate the template under h./cs'&
* the Source Creation and Management node. Right-click the template and choose ?zUV3Qgzj
* Open. You can then make changes to the template in the Source Editor. E=gD{1,?
*/ [$?S9)Xd
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package com.tot.count; x@.iDP@(
import java.util.*; qM@][]j:
/** [$3Zid
* IC[SJVH;
* @author !_<. 6ja
*/ IgEg
public class CountCache { 5WP[-J)
public static LinkedList list=new LinkedList(); 9}X3Q!iFb
/** Creates a new instance of CountCache */ mL+}Ka
public CountCache() {} Ndi'b_Sh\
public static void add(CountBean cb){ KtY~Y
if(cb!=null){ _wM[U`H}s
list.add(cb); P,h@F+OZN
} _ %&"4bm.
} )ACa0V>*p
} |NtT-T)7
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CountControl.java z1!ya#,$
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/* f]$g9H
* CountThread.java %H<w.]>
* _KmpC>J+
* Created on 2007年1月1日, 下午4:57 eJ{"\c(
* ~'fa,XZ<
* To change this template, choose Tools | Options and locate the template under BO[Q"g$Kon
* the Source Creation and Management node. Right-click the template and choose X_s;j5ur
* Open. You can then make changes to the template in the Source Editor. #CV(F$\1{
*/ i40r}?-
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package com.tot.count; o)}b Fw
import tot.db.DBUtils; 4)2*|w
import java.sql.*; Ms1\J2
/** * VW\
* ygpC1nN
* @author Vu`dEvL?
*/ tP!sOvQ:
public class CountControl{ j K[VEhs
private static long lastExecuteTime=0;//上次更新时间 a-!"m
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 1I3u~J3]/
/** Creates a new instance of CountThread */ l0D.7>aj
public CountControl() {} a0)+=*$
public synchronized void executeUpdate(){ 1b3Lan_2
Connection conn=null; +Q-~~v7,
PreparedStatement ps=null; (~Zg\(5#
try{ K1:F{*
conn = DBUtils.getConnection(); 2SG|]=
conn.setAutoCommit(false); ^0{S!fs
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); m_rR e\
for(int i=0;i<CountCache.list.size();i++){ .e.vh:Sz
CountBean cb=(CountBean)CountCache.list.getFirst(); qx0o,oZN!
CountCache.list.removeFirst(); V<4)'UI?k9
ps.setInt(1, cb.getCountId()); fbuop&FN+q
ps.executeUpdate();⑴ r@%32h
//ps.addBatch();⑵ :Yz.Bfli
} NBMY1Xgj
//int [] counts = ps.executeBatch();⑶ p6=#LwL'
conn.commit(); Arp4$h
}catch(Exception e){ @D"|Jq=6P
e.printStackTrace(); [9(B;;R@
} finally{
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try{ ;SC|VcbyH
if(ps!=null) { sef!hS06
ps.clearParameters(); 't)j
ps.close(); fE7WLV2I>
ps=null; Tg:NeAN7(
} ixKQh};5/
}catch(SQLException e){} kIWQ`)'
DBUtils.closeConnection(conn); M!X@-t#
} UO:>^,(j
} BM&'3K_y
public long getLast(){ gX(QRQ
return lastExecuteTime; v?LJ_>hw*T
} =?*V3e3{
public void run(){ 3J,/bgL5
long now = System.currentTimeMillis(); *c3o&-ke9
if ((now - lastExecuteTime) > executeSep) { 9 oq(5BG,
//System.out.print("lastExecuteTime:"+lastExecuteTime); cQ+,F2
//System.out.print(" now:"+now+"\n"); :He:Bdk
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); /=r&9P@Ay<
lastExecuteTime=now; ~o #
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executeUpdate(); .{ x5(bi0S
} P{>T?-Hj
else{ ?q,x?`|(8
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); WLh_b)V|
} LoCxoAg
} "R9kF-
} N@d4)
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 fZ
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类写好了,下面是在JSP中如下调用。 JK_$A;Q
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<% 4P:vo $Cy
CountBean cb=new CountBean(); Sr+1.77}
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); =)I{KT:y
CountCache.add(cb); O/-OW: 03
out.print(CountCache.list.size()+"<br>"); @K+u+}
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CountControl c=new CountControl(); >XZq=q]E!
c.run(); 5N|77AAxK
out.print(CountCache.list.size()+"<br>"); ]B7t9l
%>