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: mEM/}]2
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CountBean.java }s7ibm'
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/* ji~P?5(:
* CountData.java Z%uDz3I\Q"
* 'r2VWavT
* Created on 2007年1月1日, 下午4:44 6IQkP9P(
* PM
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* To change this template, choose Tools | Options and locate the template under s,2gd'
* the Source Creation and Management node. Right-click the template and choose Wz^M*=,
* Open. You can then make changes to the template in the Source Editor. DwLl}{r'
*/ sJHN4
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package com.tot.count; w'-J24>=
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/** UJX=lh.o
* :.k)!
* @author a=!I(50
*/ n~wNee
public class CountBean { R
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private String countType; J|Xu]fg0
int countId; \B<A.,i4
/** Creates a new instance of CountData */ .eSMI!Y=
public CountBean() {} \1p_6U7
public void setCountType(String countTypes){ V L&5TZtz
this.countType=countTypes; ,PyA$Z
} \EC=#E(
public void setCountId(int countIds){ )Fo1[:_B'
this.countId=countIds; D#~S<>u@
} <g^!xX<r?
public String getCountType(){
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return countType; 3?"JFfYU,'
} f/&k$,w
public int getCountId(){ \~YyY'J
return countId; mu!hD^fw
} NSPa3NE
} mh4`,N
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CountCache.java p^s k?E
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/* #Ang8O@y
* CountCache.java #O
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* mOUIGlv
* Created on 2007年1月1日, 下午5:01 U/|H%b
* u7Xr!d+wR
* To change this template, choose Tools | Options and locate the template under w<uK-]t
* the Source Creation and Management node. Right-click the template and choose qC%[J:RwF
* Open. You can then make changes to the template in the Source Editor. 6,C,LT2^(
*/ P9RIX;A=
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package com.tot.count; ?xTh}Sky
import java.util.*; g7|$JevR0
/** r:&"#F
* V@(7K0
* @author ARZ5r48)
*/ ly{Q>MBM
public class CountCache { 0F\e*{gc
public static LinkedList list=new LinkedList(); P0En&g+~
/** Creates a new instance of CountCache */ x*9CK8o=
public CountCache() {} ZL-YoMHc+_
public static void add(CountBean cb){ '|\et aD
if(cb!=null){ SseMTw:
list.add(cb); &y}nd
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} gyI(O>e
} B3P#p^
} ~[mAv#d&i
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CountControl.java BE;J/
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/* #0hX'8];(
* CountThread.java eqyZ|6
* >}43xIRRCq
* Created on 2007年1月1日, 下午4:57 ?`nF"u>
* YGA("<
* To change this template, choose Tools | Options and locate the template under Z(8'ki
* the Source Creation and Management node. Right-click the template and choose ^vPt Ppt
* Open. You can then make changes to the template in the Source Editor. _PPW9US{
*/ sh6F-g
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package com.tot.count; MBbycI,
import tot.db.DBUtils; +n
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import java.sql.*; b,U3b})(
/** M=n_;3,o
* Y!kz0([
* @author >t/P^fr_F
*/ DiB~Ovh|
public class CountControl{ 0RLyAC|
private static long lastExecuteTime=0;//上次更新时间 l#FW#`f
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 &?@gUk74"
/** Creates a new instance of CountThread */ o|s JTY
public CountControl() {} +G!N@O
public synchronized void executeUpdate(){ r~sx]=/
Connection conn=null; m})q8b!S
PreparedStatement ps=null; a:oZ5PX=
try{ Sv7_-#SW<(
conn = DBUtils.getConnection(); FA.h?yfr
conn.setAutoCommit(false); ;
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ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); s7FJJTn
for(int i=0;i<CountCache.list.size();i++){ CWVCYm@!kz
CountBean cb=(CountBean)CountCache.list.getFirst(); _u`NIpXSP
CountCache.list.removeFirst(); s_=/p5\
ps.setInt(1, cb.getCountId()); Ufz& 2
ps.executeUpdate();⑴ LiyEF&_u
//ps.addBatch();⑵ h SZ0 }/
} S^GB\uJ
//int [] counts = ps.executeBatch();⑶ 0x}8}
conn.commit(); FTy`#*7Ul
}catch(Exception e){ x9#>0
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e.printStackTrace(); ]U]22I'+$2
} finally{ C*}TY)8
try{ [mSK!Y@u
if(ps!=null) { ^KU:5Bn
ps.clearParameters(); FQR{w
ps.close(); >-Qg4%m
ps=null;
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} ^N!l$&=
}catch(SQLException e){} }LH>0v_<Y
DBUtils.closeConnection(conn); web=AQ5I4
} D!.
r$i)
}
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public long getLast(){ A2o;YyF
return lastExecuteTime; JM#jg-z,~
} d9XX^nY.
public void run(){ =a`l1zn8=
long now = System.currentTimeMillis(); g8yWFqE!T
if ((now - lastExecuteTime) > executeSep) { +e0]Y8J{
//System.out.print("lastExecuteTime:"+lastExecuteTime); !*:Zcg?7n
//System.out.print(" now:"+now+"\n"); u"K-mr#$[o
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ,`/J1(\nd
lastExecuteTime=now; O[3AI^2
executeUpdate(); !8"516!d|p
} ExDH@Lb
else{ b9[KdVsT6^
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); [_jTy;E
} TqNEU<S/t
} yA%(!v5UT
} wSp1ChS k
//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 "`DCXn#mB
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类写好了,下面是在JSP中如下调用。 Y8I$JBO
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<% ex8mA6g
CountBean cb=new CountBean(); P5ii3a?R
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); DT # 1*&-
CountCache.add(cb); Dg]ua5jk
out.print(CountCache.list.size()+"<br>"); W"fdK_F\
CountControl c=new CountControl(); B.&ly/d
c.run(); NIDK:qdR
out.print(CountCache.list.size()+"<br>"); +[9~ta|j
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