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: u~-,kF@
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CountBean.java Pi!3wy
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/* zg[.Pws:E
* CountData.java 1%^d<%,]
* kvoEnwBe_
* Created on 2007年1月1日, 下午4:44 )d^b\On
* SR<*yO
* To change this template, choose Tools | Options and locate the template under O\5q_>]
* the Source Creation and Management node. Right-click the template and choose -IP 3I
* Open. You can then make changes to the template in the Source Editor. H+O^e l
*/ "AayU
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package com.tot.count; "+BNas^rF
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/** f'-)
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* 8A,="YIt
* @author t)62_nu
*/ Qt
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public class CountBean { /iwL$xQQ
private String countType; -|/kg7IO\
int countId; C>0='@LB@r
/** Creates a new instance of CountData */ 'C")X
public CountBean() {} n?EL\B
public void setCountType(String countTypes){ @XSxoUF\
this.countType=countTypes; K]0K/~>8
} )h&*b9[B=
public void setCountId(int countIds){ c8=@s#
this.countId=countIds; =I6u*$9<
} ywl7bU-f
public String getCountType(){ M9J^;3Lrh
return countType; >.}ewz&9o
} jaOt"iU.B
public int getCountId(){ $(PWN6{\r^
return countId; d$O)k+j
} [-pB}1Dxb
} 3L5o8?[
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CountCache.java xdV $dDCT
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/* f[;l7
* CountCache.java M)T {6w
* \~{b;$N}
* Created on 2007年1月1日, 下午5:01 EvJ"%:bp
* Hrdz1:#6,
* To change this template, choose Tools | Options and locate the template under aN}l&4d
* the Source Creation and Management node. Right-click the template and choose xn`<g|"#
* Open. You can then make changes to the template in the Source Editor. 1$^=M[v
*/ <Ky6|&!
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package com.tot.count; 9>1
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import java.util.*; `tjH#W`
/** xSal=a;k
* w*3DIVlxL
* @author cz6\qSh\,
*/ VdfV5"
public class CountCache { (qky&}H
public static LinkedList list=new LinkedList(); r!,/~~mT
/** Creates a new instance of CountCache */ (9X>E+0E
public CountCache() {} `;OEdeAM
public static void add(CountBean cb){ Wt8=j1>
if(cb!=null){ ~
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list.add(cb); r:n-?P
} -1P*4H2a
} ^ 1 P@BRh
} Db5y";T
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CountControl.java cYafQyU
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/* $ [NC$*N7
* CountThread.java ti}g?\VT
* }K%y'D
* Created on 2007年1月1日, 下午4:57 Ksu_4dE
* /t<C_lLM
* To change this template, choose Tools | Options and locate the template under #VA8a=t
* the Source Creation and Management node. Right-click the template and choose *G,'V,?
* Open. You can then make changes to the template in the Source Editor. z#|#Cq`VG
*/ $kM8E@x2
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package com.tot.count; 'J=knjAT
import tot.db.DBUtils; sIZ|N"2]A*
import java.sql.*; .!&S{;Vv?W
/** F~Z~OqCS
* +#/`4EnI
* @author O@gHx! L
*/ )U':NV2
public class CountControl{ 1sHaG
private static long lastExecuteTime=0;//上次更新时间 =yZiBJ
private static long executeSep=60000;//定义更新间隔时间,单位毫秒
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/** Creates a new instance of CountThread */ nYv`{0S+m
public CountControl() {} ~1`ZPLVG
public synchronized void executeUpdate(){ e#uk+]
Connection conn=null; z12c9k%s
PreparedStatement ps=null; ?g5u#Q>!
try{ ZvS|a~jO
conn = DBUtils.getConnection(); fcC?1M[BP~
conn.setAutoCommit(false); 5jYZ+OB
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); Q5N;MpJ-
for(int i=0;i<CountCache.list.size();i++){ :le"FFfk
CountBean cb=(CountBean)CountCache.list.getFirst(); mAFVjSa2
CountCache.list.removeFirst(); npW1Z3n
ps.setInt(1, cb.getCountId()); v G7aT
ps.executeUpdate();⑴ "V:24\vO
//ps.addBatch();⑵ <f'2dT@6
} xg>AW Q
//int [] counts = ps.executeBatch();⑶ WRWcB
conn.commit(); h{sY5d'D
}catch(Exception e){ xzRs;AXOp
e.printStackTrace(); p^s k?E
} finally{ t#p*{S 3u
try{ J6)&b7
if(ps!=null) { #1v>3H(
ps.clearParameters(); J7C2:zj
ps.close(); @YMQbjbr
ps=null; \"r*wae
} 5G-}'-R
}catch(SQLException e){} g7|$JevR0
DBUtils.closeConnection(conn); r:&"#F
} 77Fpb?0`
} iSZiJ4AUq
public long getLast(){ l/JE}Eg(
return lastExecuteTime; zMXlLRC0
} :IZ(9=hs
public void run(){ ?rD`'B
long now = System.currentTimeMillis(); ^lP_{c
if ((now - lastExecuteTime) > executeSep) { ?QnVWu2K
//System.out.print("lastExecuteTime:"+lastExecuteTime); SnhB$DG
//System.out.print(" now:"+now+"\n"); RRNoX}
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); QqC4g]
lastExecuteTime=now; Eoj 2l&\
executeUpdate(); 'Gw;@[
} E/MNz}+
else{ ;,8bb(j
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); l[2 d{r
} v%e-vl
} 2nQrCdRC
} sc2nLyn$
//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 _`bH$
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类写好了,下面是在JSP中如下调用。 f4s^$Q{Q
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<% sh6F-g
CountBean cb=new CountBean(); 9P3jx)K
cb.setCountId(Integer.parseInt(request.getParameter("cid")));
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CountCache.add(cb); +n
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out.print(CountCache.list.size()+"<br>"); }^Unx W
CountControl c=new CountControl(); 9Q#eu~R
c.run(); _Gf.1Bsf@S
out.print(CountCache.list.size()+"<br>"); V0gk8wD
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