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: "k"+qR`fH
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CountBean.java d= vD Pf
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/* ?0z/i^I
* CountData.java Ty!V)i
* J-
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* Created on 2007年1月1日, 下午4:44 g?j^d:
* l)DcwkIG
* To change this template, choose Tools | Options and locate the template under 6oq^n
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* the Source Creation and Management node. Right-click the template and choose l_2l/ff9
* Open. You can then make changes to the template in the Source Editor. L4u.cHJ}0
*/ Q>w)b]d~c
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package com.tot.count; _q@lP|
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/** ? )IH#kL
* ^Nav8dma
* @author R*ex!u60M
*/ wc}x
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public class CountBean { }+[!h=Bx
private String countType; Y<@_d
int countId; l:#'i`;
/** Creates a new instance of CountData */ slr>6o%W`
public CountBean() {} U&$I!80.
public void setCountType(String countTypes){ <A\g*ld
this.countType=countTypes; JiA1yt
} >:
@\SU
public void setCountId(int countIds){ kY4h-oZ
this.countId=countIds; [P)](8nR[
} 5*B'e{C
public String getCountType(){ mkBQTQGT
return countType; .rDao]K
} C<^S$
public int getCountId(){ b3GTsX\2|
return countId; &s\,+d0
} rg%m
} D[YdPg@-
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CountCache.java ^:O*Sx.CA
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/* DuQ:82 3b
* CountCache.java >Bm>/%2
* $'a]lR
* Created on 2007年1月1日, 下午5:01 lL'K1%{+
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* ^ilgd
* To change this template, choose Tools | Options and locate the template under Ut2x4$9
* the Source Creation and Management node. Right-click the template and choose QYBLU7
* Open. You can then make changes to the template in the Source Editor. zFwO(
*/ eo"XHP7ja
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package com.tot.count; ')fIa2dO/
import java.util.*; "(+aWvb
/** GsqO^SV
* 8h|~>v
* @author Z3Xgi~c
*/ N71^ I"@HH
public class CountCache { ZU9Rvtb KB
public static LinkedList list=new LinkedList(); B,4GxoX`
/** Creates a new instance of CountCache */ FQMA0"(G$
public CountCache() {} lcoJ1+`C
public static void add(CountBean cb){ W;,RU8\f
if(cb!=null){ w;Pe_m7\EO
list.add(cb); `-rtU
} H[r6 4~Sth
} $T2zs$
} 1<M~#
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CountControl.java z7*mT}Q
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/* ,#.^2O9-^
* CountThread.java 3ZYrNul"
* rN {5^+w
* Created on 2007年1月1日, 下午4:57 `zcpaE.@
* :\1vy5 _
* To change this template, choose Tools | Options and locate the template under W5RZsS]
* the Source Creation and Management node. Right-click the template and choose -dUXd<=ue
* Open. You can then make changes to the template in the Source Editor. }-WuHh#
*/ wmX * n'l
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package com.tot.count; ^DR`!.ttr
import tot.db.DBUtils; ~^eC?F(
import java.sql.*; fhQ N;7
/** -]MZP:s
* O<0-`=W,a
* @author 8O^z{Yh7
*/ 7q^a@5f BG
public class CountControl{ xSjs+Y;Mu
private static long lastExecuteTime=0;//上次更新时间 sQY0Xys<4
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 Bq\WG=Fd
/** Creates a new instance of CountThread */ /9C>{29x!
public CountControl() {} jATN):8W
public synchronized void executeUpdate(){ 4+0:(=>[%
Connection conn=null; s3 gT6
PreparedStatement ps=null; b=Q%Jxz?
try{ DTx>^<Tk
conn = DBUtils.getConnection(); O@KAh5EB
conn.setAutoCommit(false); A Rjox`
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); IAbH_+7O
for(int i=0;i<CountCache.list.size();i++){ sVIw'W
CountBean cb=(CountBean)CountCache.list.getFirst(); E`3[62C
CountCache.list.removeFirst(); Z9PG7h
ps.setInt(1, cb.getCountId()); ]<E\J+5K
ps.executeUpdate();⑴ _5768G`P
//ps.addBatch();⑵ `"E<%$|ZQy
} xTdh/}
//int [] counts = ps.executeBatch();⑶ ZCkwK
conn.commit(); HBgt!D0MZ
}catch(Exception e){ MqswYK-s
e.printStackTrace(); |Iq\ZX%q
} finally{ cz*Z/5XH
try{ WAh{*$Rpl
if(ps!=null) { *s"{JrG`O
ps.clearParameters(); {UEZ:a
ps.close(); as@I0e((
ps=null; p4wXsOQ}
} Aj2yAg
}catch(SQLException e){} '\Hh
DBUtils.closeConnection(conn); l,M?
} ;jpsH?3g
} .AHww7
public long getLast(){ T$9tO{
return lastExecuteTime; c5tCw3$t
} B976{;QvXV
public void run(){ {= l9{K`~
long now = System.currentTimeMillis(); C+c;UzbD
if ((now - lastExecuteTime) > executeSep) { t[ ^68]
//System.out.print("lastExecuteTime:"+lastExecuteTime); @{UtS2L
//System.out.print(" now:"+now+"\n"); 9.$k^|~
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); XhJbBVS|
lastExecuteTime=now; /*{s1Zcb
executeUpdate(); #s^~'2^%4
} pD%Pg5p`
else{ v`pIovn
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); H!dg(d^
} HrQft1~N
} djtCv;z
} F:rT.n
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 c4n]#((%a
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类写好了,下面是在JSP中如下调用。 YXhxzH hPd
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<% 2p|[yZ
CountBean cb=new CountBean(); L+y90 T6?
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); Ce1^S[
CountCache.add(cb); yGtGhP8
out.print(CountCache.list.size()+"<br>"); =;^#5dpt$
CountControl c=new CountControl(); Zo|# ,AdE>
c.run(); 3 ]}wZY0
out.print(CountCache.list.size()+"<br>"); Kr|9??`0E
%>