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: FE\E%_K'n7
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CountBean.java FB[b]+t`D{
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/* rJ Jx8)M
* CountData.java btuG%D{a^
* oIE
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* Created on 2007年1月1日, 下午4:44 )$:1e)d
* eLSzGbKf
* To change this template, choose Tools | Options and locate the template under Ma|4nLC}
* the Source Creation and Management node. Right-click the template and choose G$>?UQ[
* Open. You can then make changes to the template in the Source Editor. ekhv.;N~
*/ 3:x(2 A
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package com.tot.count; Q-w# !<L.
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/** Q]K` p(
* ,,{;G'R|
* @author s$Y>nH~T
*/ gTho:;q7a
public class CountBean { i\6CE|
private String countType; DEZww9T2Qs
int countId; \EfX3ghPI
/** Creates a new instance of CountData */ lD,2])>
public CountBean() {} .rtA sbp.!
public void setCountType(String countTypes){ L~6%Fi&n4
this.countType=countTypes; BTkx}KK
} (zo7h
public void setCountId(int countIds){ G]=z
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this.countId=countIds; _Q5mPBO
} ~</FF'Xz
public String getCountType(){ !1)aie+p6
return countType; ",b:rgpRp
} 5*%Gh&)
public int getCountId(){ m8fj\,X
return countId; bp?5GU&Uy
} ^&?,L@fW
} gyvrQ, u
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CountCache.java a!$kKOK
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/* cj[b ^Wv:
* CountCache.java 0VNLhM(LM
* >s^$-
* Created on 2007年1月1日, 下午5:01 l53i
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* >_?i)%+)
* To change this template, choose Tools | Options and locate the template under "|8oFf)l@B
* the Source Creation and Management node. Right-click the template and choose eq6O6-
* Open. You can then make changes to the template in the Source Editor. DC8#b`j
*/ ~*iF`T6
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package com.tot.count; |C4fg6XDL
import java.util.*; ^#:;6^Su
/** 072C!F
* }93kHO{
* @author C^)Imr
*/ z By%=)`
public class CountCache { -%`~3*L
public static LinkedList list=new LinkedList(); (TT=i
/** Creates a new instance of CountCache */ 6|jZv~rS$
public CountCache() {} &42]#B"*
public static void add(CountBean cb){ Ooz,?wU6
if(cb!=null){ .==D?#bn
list.add(cb); *k LFs|U
} /L^g. ~
} +Ryj82;59z
}
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CountControl.java ]@$^Ju,
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/* ~~/,2^
* CountThread.java Z Ts*Y,
* y74Q(
* Created on 2007年1月1日, 下午4:57 ^@^8iZ
* ;\RVC7
* To change this template, choose Tools | Options and locate the template under 40kAGs>_
* the Source Creation and Management node. Right-click the template and choose i6if\B
* Open. You can then make changes to the template in the Source Editor. sq'm)g
*/ kOQ)QX
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package com.tot.count; ztO)~uL
import tot.db.DBUtils; +KTfGwKt
import java.sql.*; 7%^G]AFi
/** /I 7V\
* Ugri _
* @author 8oX1 F(R
*/ ]\M{Abqd{
public class CountControl{ VIp|U{
private static long lastExecuteTime=0;//上次更新时间 9mi@PW}1
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ]U>MYdGWb
/** Creates a new instance of CountThread */ q }@L "a`
public CountControl() {} hZ4 5i?%
public synchronized void executeUpdate(){ |A3"Jc.2o
Connection conn=null; IBT>&(cnV
PreparedStatement ps=null; w0BphK[
try{ pQa51 nc
conn = DBUtils.getConnection(); =0cTct6\
conn.setAutoCommit(false); rbd0`J9fq
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); Dd?G4xUG
for(int i=0;i<CountCache.list.size();i++){ agUdI_'~@9
CountBean cb=(CountBean)CountCache.list.getFirst(); JG!B3^qB
CountCache.list.removeFirst(); >+%#m'Y&&
ps.setInt(1, cb.getCountId()); wo`.sB&T
ps.executeUpdate();⑴ 8:TX9`,
//ps.addBatch();⑵ 7:UeE~uB:
} x$LCLP#$H
//int [] counts = ps.executeBatch();⑶ }3*<sxw7<
conn.commit(); Bq8#'K2i,
}catch(Exception e){ xGsOnY;
e.printStackTrace(); V(&L
} finally{ *u$aItx
try{ *Dp&;, b
if(ps!=null) { 1mmL`M1
ps.clearParameters(); eHgr"f*7
ps.close(); CF;Gy L1M
ps=null; r)t[QoD1
} wiN0|h>,
}catch(SQLException e){} |ty&}'6C
DBUtils.closeConnection(conn); )U\i7[k>
} t utk*|S
} e1Db
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public long getLast(){ e4YfJd
return lastExecuteTime; @D9O<x
} 1n`[D&?q
public void run(){ ? $B4'wc5
long now = System.currentTimeMillis(); Km5_P##
if ((now - lastExecuteTime) > executeSep) { Gld~GyB\k
//System.out.print("lastExecuteTime:"+lastExecuteTime); @)b'3~D
//System.out.print(" now:"+now+"\n"); _A,_RM$Y
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); (>}1t!1
lastExecuteTime=now; 'Dfs&sm
executeUpdate(); p\[!=ZXFr\
} 5HbHJ.|r
else{ \m7\}Nbz0/
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); W et0qt]
} ;#Po}8Y=
} ?T/4
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} WM+8<|)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 s\d3u`G
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类写好了,下面是在JSP中如下调用。 I=L["]
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<% eCI'<^
CountBean cb=new CountBean(); vsI;ooR>
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); R2)@Q
CountCache.add(cb); C@qWour
out.print(CountCache.list.size()+"<br>"); XIIq0I
CountControl c=new CountControl(); %wbdg&^
c.run(); u(Mbp$R'?
out.print(CountCache.list.size()+"<br>"); ?i<l7
%>