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: q?oJ=]m"
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CountBean.java !7anJl
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/* wq3 V&@.
* CountData.java \8SHX
* qzu%Pp6If
* Created on 2007年1月1日, 下午4:44 ,lw<dB@7"5
* b"z9Dp v
* To change this template, choose Tools | Options and locate the template under XcQ'(
* the Source Creation and Management node. Right-click the template and choose 0N3S@l#,\A
* Open. You can then make changes to the template in the Source Editor. jz$83TB-
*/ HltURTbI
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package com.tot.count; Q_n9}LanP
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/** s)|l-I
* :#p!&Fi
* @author ]6EXaf#
*/ -%)8=
public class CountBean { w~=@+U$f
private String countType; y'pX/5R0
int countId; #-u?+Nk/
/** Creates a new instance of CountData */ #&c}in"!
public CountBean() {} )haHI)xR
public void setCountType(String countTypes){ xkebel`%
this.countType=countTypes; We,~P\g
} a"0'cgB}
public void setCountId(int countIds){ IK^jzx
this.countId=countIds; (1b%);L7
} Cdd
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public String getCountType(){ ,b8q$R~\
return countType; 2*1s(Jro
} ZX!u\O|w
public int getCountId(){ .EUOKPK4W
return countId; 1 ~#p3)B
} *QpKeI
} a<K@rgQ
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CountCache.java nY<hfqof
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/* .v:K`y;f\(
* CountCache.java N;6WfdA-
* K)"cwk-
* Created on 2007年1月1日, 下午5:01 ]n:)W.|`R
* O{9h'JU
* To change this template, choose Tools | Options and locate the template under l`R/WC
* the Source Creation and Management node. Right-click the template and choose VJeN
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* Open. You can then make changes to the template in the Source Editor. >2l;KVm%
*/ O2Mo ~}
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package com.tot.count; UC34AKm
import java.util.*; fH7o,U|
/** X|7Y|0o
* }GCt)i_
* @author Whq@>pX8
*/ r='"X#CmV/
public class CountCache { +`x8[A)-
public static LinkedList list=new LinkedList(); "3v[\M3
/** Creates a new instance of CountCache */ j9za)G-J
public CountCache() {} /)PD+18
public static void add(CountBean cb){ lc=C
if(cb!=null){ PQRh5km
list.add(cb); 8 JUUK(&Z
} B;?"R
} )-2o}KU]>
} hb"t8_--c
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CountControl.java z2&SZ.mk
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/* |wZ8O}O{E
* CountThread.java oO|zRK1;/
*
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* Created on 2007年1月1日, 下午4:57 ,iU ]zN//
* hp}J_/+4n
* To change this template, choose Tools | Options and locate the template under Dm6}$v'0
* the Source Creation and Management node. Right-click the template and choose pI
|;
* Open. You can then make changes to the template in the Source Editor. p
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*/ qDO4&NO
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package com.tot.count; FG-w7a2mn
import tot.db.DBUtils; PY.c$)az>
import java.sql.*; A}sb2P
/** {b>tX)Tep
* 2i4FIS|z0
* @author
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*/ A?3hNvfx
public class CountControl{ a4X J0Tm
private static long lastExecuteTime=0;//上次更新时间 )kl| 5i
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 pK#Ze/!
/** Creates a new instance of CountThread */ x{C=r dp__
public CountControl() {} j[yGfDb
public synchronized void executeUpdate(){ =8j;!7p
Connection conn=null; viAvD6e
PreparedStatement ps=null; E) >~0jv
try{ _$By c(.c
conn = DBUtils.getConnection(); 0%}$@H5i
conn.setAutoCommit(false); *~fZ9EkD
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ~-Rr[O=E
for(int i=0;i<CountCache.list.size();i++){ _Q/D%7[pa
CountBean cb=(CountBean)CountCache.list.getFirst(); 46*o_A,"
CountCache.list.removeFirst(); L._I"g5 H9
ps.setInt(1, cb.getCountId()); 0X -u'=Bs
ps.executeUpdate();⑴ BN@*CG
//ps.addBatch();⑵ !'B.ad
} b/ 'fC%o,
//int [] counts = ps.executeBatch();⑶ "tUXYY
conn.commit(); <dDGV>n4;
}catch(Exception e){ GdR>S('
e.printStackTrace(); ,Z#t-?
} finally{ SZ~Ti|^
try{ EKk~~PhW 8
if(ps!=null) { B @UaaWh
ps.clearParameters(); ,m!j2H}8
ps.close(); m1VyYG
ps=null; ._=Pa)T
} NyJU?^f&v
}catch(SQLException e){} O qY8\>f-
DBUtils.closeConnection(conn); on(F8%]zE
} |h*H;@$
} 4*lShkL
public long getLast(){ 4kNf4l9Y
return lastExecuteTime; 0X`Qt[
} 06pLa3oi
public void run(){ [L|H1ll
long now = System.currentTimeMillis(); -f z
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if ((now - lastExecuteTime) > executeSep) { Tm_AoZH
//System.out.print("lastExecuteTime:"+lastExecuteTime); U{RW=sYB~9
//System.out.print(" now:"+now+"\n"); 4/S4bk*8
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); [E2afC>zrl
lastExecuteTime=now; Y1H8+a5@
executeUpdate(); )}=`Gx5+
} - P1OD)B
else{ 5Qo\0YH
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); -wC;pA#o
} ln'7kg
} utQE$0F
} ^u:7U4
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 .Hl]xI$;+
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类写好了,下面是在JSP中如下调用。 qWGnIPk
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<% _,=A\C_b@
CountBean cb=new CountBean(); KFdV_e5lU
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 9loWh5_1Z
CountCache.add(cb); dfiA- h
out.print(CountCache.list.size()+"<br>"); g6IG>)
CountControl c=new CountControl(); BP,"vq $'+
c.run();
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out.print(CountCache.list.size()+"<br>"); GX&BUP\
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