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: .H5^ N\V|
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CountBean.java ZZW%6 -B
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/* iD:TKB_r
* CountData.java -M`+hVs?
* }M9I]\
* Created on 2007年1月1日, 下午4:44 (vbI4&r
* >):>Pz%U
* To change this template, choose Tools | Options and locate the template under "^Vfo$q
* the Source Creation and Management node. Right-click the template and choose DcZ,a E]
* Open. You can then make changes to the template in the Source Editor. UFr5'T
*/ 3n1 >+8
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package com.tot.count; k
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/** %eE 6\f%g
* D}bCMN<
* @author =|q@Q`DB
*/ P".rm0@R
public class CountBean { IPlkv{^
private String countType; \xOv 9(
int countId; l`*R !\
/** Creates a new instance of CountData */ 'k9 1;T[
public CountBean() {} o>\epQt~/p
public void setCountType(String countTypes){ rd}|^&e!Dy
this.countType=countTypes; ,}$[;$ye
}
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public void setCountId(int countIds){ DbK-3F_
this.countId=countIds; );V.le}%(
} r1|;V~a$~
public String getCountType(){ bcFZ ~B
return countType; s!/Q>A
} s C?-L
public int getCountId(){ UjS,<>fm
return countId; /@K1"/fqH
} o,=dm@j
} I>spJ5ls
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CountCache.java e}W|wJ):j@
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/* 'E#Bz"T
* CountCache.java =' #yG(h
* <z-+{-?z~
* Created on 2007年1月1日, 下午5:01 |&rxDf}W
* Np R&`]
* To change this template, choose Tools | Options and locate the template under KoTQc0b!
* the Source Creation and Management node. Right-click the template and choose hSSFmEpr
* Open. You can then make changes to the template in the Source Editor. -<aN$O
*/ DsGtc<l%
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package com.tot.count; 7cZ(g dQ/
import java.util.*; %x|0<@b7-
/** z4*`K4W
* &13#/
* @author 1WLaJ%Fv
*/ psE&Rx3)
public class CountCache { O\)rp!i
public static LinkedList list=new LinkedList(); UWq[K&vQZ
/** Creates a new instance of CountCache */ T&kr IZw
public CountCache() {} R]Pv=fn
public static void add(CountBean cb){ VeWvSIP,EQ
if(cb!=null){ G^_fbrZjN
list.add(cb); r
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} x<[W9Z'~?9
} Y%)@)$sK
} Y`
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CountControl.java BFMINq>
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/* OqA#4h4^
* CountThread.java :LBRyBV
* aak[U;rx
* Created on 2007年1月1日, 下午4:57 }`$Sr&n 1
* RJT=K{2x
* To change this template, choose Tools | Options and locate the template under S(h+,+289
* the Source Creation and Management node. Right-click the template and choose \>r<z46x
* Open. You can then make changes to the template in the Source Editor. Tjza3M
*/ 8yn}|Y9Fu
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package com.tot.count; g:CMIe4
import tot.db.DBUtils; e khx?rz
import java.sql.*; W&8)yog.
/** cAc>p-y%
* <46fk*
* @author V<G=pPC'H
*/ @b"J FB|
public class CountControl{ `f+l\'.s
private static long lastExecuteTime=0;//上次更新时间 e`Vb.E)
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 AH#klYK
/** Creates a new instance of CountThread */ uO;_T/^u
public CountControl() {} T_*R^Ukb5
public synchronized void executeUpdate(){ q3-V_~5^/z
Connection conn=null; OMVK\_oXo
PreparedStatement ps=null; W4o$J4IX{
try{ 0*}%v:uN9
conn = DBUtils.getConnection(); )Y@mL/_
conn.setAutoCommit(false); W:
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ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); l|p
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for(int i=0;i<CountCache.list.size();i++){ ?:XbZ"25pJ
CountBean cb=(CountBean)CountCache.list.getFirst(); "OO"Ab{t
CountCache.list.removeFirst(); HCTjFW>C
ps.setInt(1, cb.getCountId()); o&b1-=MC2
ps.executeUpdate();⑴ 3,RaM^5dV
//ps.addBatch();⑵ SN/
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} |]8Hh>
//int [] counts = ps.executeBatch();⑶ Foc) u~
conn.commit(); 9py*gN#
}catch(Exception e){ /K<.$B8
e.printStackTrace(); UuvI?D
} finally{ n; fUwon
try{ 9>na3ISh
if(ps!=null) { +Pm
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ps.clearParameters(); (r+#}z}
ps.close(); 'CSIC8M<j
ps=null; |VRzIA4M\
} *Af:^>mh
}catch(SQLException e){} }+Ne)B E
DBUtils.closeConnection(conn); jLu`DKB
} K}p!W"!o
} W4~:3Sk
public long getLast(){ Ot#O];3
return lastExecuteTime; `$odxo+
} G 0;5I_D/
public void run(){ :RE.m d
long now = System.currentTimeMillis(); Ysz&/ry
if ((now - lastExecuteTime) > executeSep) { ApxGrCu
//System.out.print("lastExecuteTime:"+lastExecuteTime); i-`n5,
//System.out.print(" now:"+now+"\n"); R<jt$--H
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); }+4^ZbX+:
lastExecuteTime=now; ee|i
executeUpdate(); 1EvK\
} {Ex*8sU%p%
else{ %t:pG}A>:C
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); LCMCpEtY*K
} 3A(sT}
} aOH$}QnS
} Eu^?e
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释
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类写好了,下面是在JSP中如下调用。 SsE8;IGH
"Wz#<! .r
<% . w_oW mD
CountBean cb=new CountBean(); }t^N|I
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 5 UQbd8
CountCache.add(cb); NY`$D}Bi
out.print(CountCache.list.size()+"<br>"); ,>rr|O
CountControl c=new CountControl(); Rr|&~%#z
c.run(); <s7OY`(8
out.print(CountCache.list.size()+"<br>"); wtY*{m2
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