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: v/GZByco>
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CountBean.java *3A)s
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/* hkDew0k
* CountData.java
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* D16w!Mnz{K
* Created on 2007年1月1日, 下午4:44 2I>`{#fV
* r:U/a=V
* To change this template, choose Tools | Options and locate the template under ~F.kgX
* the Source Creation and Management node. Right-click the template and choose :;URLl0
* Open. You can then make changes to the template in the Source Editor. *[+{KJ
*/ nU,~*Us
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package com.tot.count; eE5j6`5i
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/** NRMEZ\*L
* +GL[uxe"
* @author #:xv]qb`k
*/ Zo#c[9IaC
public class CountBean { <T`&NA@%~$
private String countType; f taa~h*
int countId; ` 1vDp.
/** Creates a new instance of CountData */ BV)) #D9
public CountBean() {} vEc<|t
public void setCountType(String countTypes){ c+ukVn`r
this.countType=countTypes; Y(;u)uN_
} 4G'-"u^g
public void setCountId(int countIds){ z#GrwE,r
this.countId=countIds; =h\uC).t&
} mCSt.n~
public String getCountType(){ FnCMr_
return countType; \ch4c9
} [{.9#cQ"
public int getCountId(){ t[p/65L>8
return countId; @;7Ht Z`
} 9R99,um$
} ^[.Z~>3!\q
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CountCache.java ]VoJ7LoCZ'
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/* [8'^"
* CountCache.java NL-V",gI-~
* hg-M>|s7
* Created on 2007年1月1日, 下午5:01 4"s/T0C
* 9.wZhcqqU
* To change this template, choose Tools | Options and locate the template under FyqsFTh_
* the Source Creation and Management node. Right-click the template and choose P-\65]`C
* Open. You can then make changes to the template in the Source Editor. 3'!*/UnU
*/ N6BEl55 &
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package com.tot.count; S{nBQB<
import java.util.*; Qov*xRO6
/** 4k)0OQeW6
* %(B6eiA
* @author g(l:>=g]?
*/ T U^s!Tj
public class CountCache { P\%aJ'f~
public static LinkedList list=new LinkedList(); ^!Tq(t5V
/** Creates a new instance of CountCache */ 5l]qhi3f
public CountCache() {} [tkP2%1
public static void add(CountBean cb){ BFQ`Ab+
if(cb!=null){ =%d.wH?dZ/
list.add(cb); 9>/:c\q+
} 'H(khS
} :8U@KABH@h
} 2Yg\<PsN
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CountControl.java 0RHjA&r3v
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/* z{nd4qOsD
* CountThread.java 7!JBF{,=
* Pv\-D<&@m
* Created on 2007年1月1日, 下午4:57 oO9yI^
* ~H:.&'E
* To change this template, choose Tools | Options and locate the template under W)Mc$`nX
* the Source Creation and Management node. Right-click the template and choose ?ajVf./Ja
* Open. You can then make changes to the template in the Source Editor. \{54mM~
*/ u@T,8
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package com.tot.count; w01u~"E
import tot.db.DBUtils; (^$SMuC
import java.sql.*; @@& ?,3
/** ,"f2-KC4h
* >2mV{i&
* @author fJ;1ii~
*/ pg3h>)$/
public class CountControl{ \9 k3;zw
private static long lastExecuteTime=0;//上次更新时间 FO)`&s"&2
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 wu3p2#-Z
/** Creates a new instance of CountThread */ wRJ`RKJ-T
public CountControl() {} 9'A^n~JHF
public synchronized void executeUpdate(){ [_HOD^
Connection conn=null; w
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PreparedStatement ps=null; toel!+
try{ 8@]vvZ2/gj
conn = DBUtils.getConnection(); XhmUtbs
conn.setAutoCommit(false); vP^V3
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ASa)xf9
for(int i=0;i<CountCache.list.size();i++){ f`-UC_(;
CountBean cb=(CountBean)CountCache.list.getFirst(); |3Bmsd/3
CountCache.list.removeFirst(); ZdlQ}l#F
ps.setInt(1, cb.getCountId()); C;m*0#9D
ps.executeUpdate();⑴ ]~9YRVeC
//ps.addBatch();⑵ S5e"}.]|
} \vgM`32<
//int [] counts = ps.executeBatch();⑶ 4S*dNYc
conn.commit(); "]B%V!@
}catch(Exception e){ Jm-bE 8b
e.printStackTrace(); ?pV!`vp^{
} finally{ yUvn h
try{ 0A F}wz>
if(ps!=null) { 6Ok]E`
ps.clearParameters(); qP72JxT
ps.close(); x<=R?4@rq
ps=null; g5t`YcL
} z0?IQzR^T
}catch(SQLException e){} 7%5EBH &
DBUtils.closeConnection(conn); HAAU2A9B2
} Wo~;h(6
} g1&q6wCg|
public long getLast(){ %(>,eee_
return lastExecuteTime; z)%]#QO
} pQk@
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public void run(){ S^nI=HTm
long now = System.currentTimeMillis(); >~})O&t
if ((now - lastExecuteTime) > executeSep) { Ly]J-BTe
//System.out.print("lastExecuteTime:"+lastExecuteTime); WT:ZT$W
//System.out.print(" now:"+now+"\n"); :~'R| l
// System.out.print(" sep="+(now - lastExecuteTime)+"\n");
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lastExecuteTime=now; ?cB26Zrcb
executeUpdate(); {=9"WN
} (1Klj+"p%
else{ dg4q+
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); FBS]U$1
} 9/dADJe0b
} e,T^8_>
} qD{~QHDa
//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 _ c,{}sn
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类写好了,下面是在JSP中如下调用。 QZFH>,d
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<% I[bWd{i:
CountBean cb=new CountBean(); af|x(:!H
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 41I2t(H @z
CountCache.add(cb); $8>II0C.
out.print(CountCache.list.size()+"<br>"); wS+j^
;"
CountControl c=new CountControl(); 0}WDB_L
c.run(); 7|(o=+Bt
out.print(CountCache.list.size()+"<br>"); fzzk#jU
%>