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: BlL|s=dlQV
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CountBean.java 9t#P~>:jY}
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/* g`kY]lu
* CountData.java ZOp^`c9~
* oL#xDG
* Created on 2007年1月1日, 下午4:44 ]+mjOks~
* 3u*82s\8T
* To change this template, choose Tools | Options and locate the template under jH(&oV
* the Source Creation and Management node. Right-click the template and choose J`W-]3S#
* Open. You can then make changes to the template in the Source Editor. A1Ka(3"
*/ -H`\?
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package com.tot.count; 9MT? .q
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/** s\_l=v3
*
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* @author z9 O~W5-U
*/ UkZ\cc}aC/
public class CountBean { z/weit
private String countType; _$8{;1$T?
int countId; 8qN"3 Et
/** Creates a new instance of CountData */ m#*h{U$
public CountBean() {} ("OAPr\2dw
public void setCountType(String countTypes){ vm|!{5l:=y
this.countType=countTypes; i =-8@
} WK*S4c
public void setCountId(int countIds){ R+d<
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this.countId=countIds; _AprkI_
} mGO>""<:
public String getCountType(){ `YU=~xQ
return countType; 2yvVeo&3
} #\LZ;&T'N
public int getCountId(){ "NKf0F
return countId; U~wjR"='
} JIMWMk;ot
} o*-9J2V=J
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CountCache.java eHUg-\dy
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/* Hng!'
* CountCache.java 7D
* U-eI\Lu
* Created on 2007年1月1日, 下午5:01 3?@?-q2g
* 7lR<@$q
* To change this template, choose Tools | Options and locate the template under |0kXCq
* the Source Creation and Management node. Right-click the template and choose Y87XLvig}
* Open. You can then make changes to the template in the Source Editor. +TF8WZZF.d
*/ g,=^'D
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package com.tot.count; &L%Jy #=
import java.util.*; ;gUXvx~~r
/** x/xb1"
* Pxqiv9D<R
* @author =-Nsc1&
*/ ~,gLplpG0
public class CountCache { HxZ.OZbR
public static LinkedList list=new LinkedList(); ;SKcbws
/** Creates a new instance of CountCache */ +;dXDZ2
public CountCache() {} q? 9GrwL8F
public static void add(CountBean cb){ ]IS;\~
if(cb!=null){ 4%J|D cY2
list.add(cb); &wjB{%
} NF mc>0-
} p,;mYm s
} {]`p&@
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CountControl.java f`?0WJ(M
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/* B6MkF"J<
* CountThread.java 3fp> 4;ym'
* m2 O&2[g
* Created on 2007年1月1日, 下午4:57 \2>?6zs
* nvt$F%+
* To change this template, choose Tools | Options and locate the template under k;Hnu
* the Source Creation and Management node. Right-click the template and choose I+",b4
* Open. You can then make changes to the template in the Source Editor. AkA!:!l
*/ "r. .
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package com.tot.count; 'E -FO_N
import tot.db.DBUtils; |` "?
import java.sql.*; 2m" _z
/** 'M N1A;IJ
* +/y]h0aa
* @author gu<V(M\
*/ \[ M_\&GC
public class CountControl{ $;`I,k$0>~
private static long lastExecuteTime=0;//上次更新时间 [;^,CD|P
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 =|,A%ZGF$
/** Creates a new instance of CountThread */ :u/mTZDi
public CountControl() {} 41yOXy ;~l
public synchronized void executeUpdate(){ qfrNi1\9-
Connection conn=null; ^A!$i$NON
PreparedStatement ps=null; q@ZlJ3%l,
try{ |')-VhLLK
conn = DBUtils.getConnection(); NXI[q'y
conn.setAutoCommit(false); hcyO97@r
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); .S7:;%qL6
for(int i=0;i<CountCache.list.size();i++){
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CountBean cb=(CountBean)CountCache.list.getFirst(); [PWL<t::c
CountCache.list.removeFirst(); kjE*9bUc
ps.setInt(1, cb.getCountId()); Q["t eo]DQ
ps.executeUpdate();⑴ ehT%s+aUw
//ps.addBatch();⑵ ~5 >[`)
} 55m<XC
//int [] counts = ps.executeBatch();⑶ {G*OR,HN
conn.commit(); !d8A
}catch(Exception e){ <2<87PU
e.printStackTrace(); pbLGe'
} finally{ d~Mg
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try{ S
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if(ps!=null) { 78]gtJ
ps.clearParameters(); &{z<kmc$6
ps.close(); P^i.La,
ps=null; E\$C/}T
} 2|{V,!/cvG
}catch(SQLException e){} #SnvV
DBUtils.closeConnection(conn); 3Aj*\e0t
} Wi$dZOcSJ
} FjFwvO_.
public long getLast(){ .Dw,"VHP
return lastExecuteTime; ~xDw*AC-
} x_!ZycEa
public void run(){ z<&m*0WYA
long now = System.currentTimeMillis(); Lh ap4:
if ((now - lastExecuteTime) > executeSep) { /!T> b:0
//System.out.print("lastExecuteTime:"+lastExecuteTime); SlaDt
//System.out.print(" now:"+now+"\n"); > 0.W`j(s
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); dR+1aY;
lastExecuteTime=now; 4!%F\c46
executeUpdate(); B42sb_
} BsLG^f
else{ W^3;F1
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 1@_T m
} n:4uA`Vg
} Z
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} /3B6Mtb
//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 1%`7.;!i
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类写好了,下面是在JSP中如下调用。 Tlodn7%",
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<% GEe`ZhG,
CountBean cb=new CountBean(); J/ W{/E>;
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); RU&_j*U
CountCache.add(cb); Bs!4H2@{(]
out.print(CountCache.list.size()+"<br>"); FxRXPt
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CountControl c=new CountControl(); r;gP}H ?
c.run(); |d}MxS`^
out.print(CountCache.list.size()+"<br>"); 2UadV_s+s
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